Remove JAXB and XML, use GSON for JSON

This review converst apex-pdp to use GSON for JSON handling. In order to
preserve backward compatibility with the JAXB format of JSON, custom
handling of maps was required. Therefore, the policy-common
StandardCoder could not be used.

There are a lot of small changes, removing annotations from concepts and
tweaking of test data. However, this cleans up the code base so it is
worth doing.

Issue-ID: POLICY-1820
Change-Id: I213fa64f6d7f3f1df8d10f111d9fbedbe80f9fe0
Signed-off-by: liamfallon <liam.fallon@est.tech>

33 files changed, 393 insertions, 1508 deletions

diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxArtifactKey.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxArtifactKey.java
index f5d421956..1efe83db8 100644
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxArtifactKey.java
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxArtifactKey.java
@@ -23,11 +23,6 @@ package org.onap.policy.apex.model.basicmodel.concepts;
 
 import java.util.ArrayList;
 import java.util.List;
-import javax.xml.bind.annotation.XmlAccessType;
-import javax.xml.bind.annotation.XmlAccessorType;
-import javax.xml.bind.annotation.XmlElement;
-import javax.xml.bind.annotation.XmlRootElement;
-import javax.xml.bind.annotation.XmlType;
 import org.onap.policy.apex.model.basicmodel.concepts.AxValidationResult.ValidationResult;
 import org.onap.policy.common.utils.validation.Assertions;
 
@@ -39,22 +34,13 @@ import org.onap.policy.common.utils.validation.Assertions;
  * <p>Key validation checks that the name and version fields match the NAME_REGEXP and VERSION_REGEXP
  * regular expressions respectively.
  */
-@XmlAccessorType(XmlAccessType.FIELD)
-@XmlRootElement(name = "apexArtifactKey", namespace = "http://www.onap.org/policy/apex-pdp")
-
-@XmlType(name = "AxArtifactKey", namespace = "http://www.onap.org/policy/apex-pdp", propOrder =
-    { "name", "version" })
-
 public class AxArtifactKey extends AxKey {
     private static final long serialVersionUID = 8932717618579392561L;
 
     private static final String NAME_TOKEN = "name";
     private static final String VERSION_TOKEN = "version";
 
-    @XmlElement(required = true)
     private String name;
-
-    @XmlElement(required = true)
     private String version;
 
     /**
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxConcept.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxConcept.java
index 0e2c6bef2..37fe30b33 100644
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxConcept.java
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxConcept.java
@@ -1,7 +1,7 @@
 /*-
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- *  Modifications Copyright (C) 2019 Nordix Foundation.
+ *  Modifications Copyright (C) 2019,2022 Nordix Foundation.
  *  Modifications Copyright (C) 2021 AT&T Intellectual Property. All rights reserved.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -24,7 +24,6 @@ package org.onap.policy.apex.model.basicmodel.concepts;
 
 import java.io.Serializable;
 import java.util.List;
-import javax.xml.bind.annotation.XmlType;
 import org.onap.policy.common.utils.validation.Assertions;
 
 /**
@@ -33,9 +32,6 @@ import org.onap.policy.common.utils.validation.Assertions;
  *
  * @author Liam Fallon (liam.fallon@ericsson.com)
  */
-
-@XmlType(name = "AxConcept", namespace = "http://www.onap.org/policy/apex-pdp")
-
 public abstract class AxConcept implements Serializable, Comparable<AxConcept> {
     private static final long serialVersionUID = -7434939557282697490L;
 
@@ -86,6 +82,12 @@ public abstract class AxConcept implements Serializable, Comparable<AxConcept> {
     public abstract void clean();
 
     /**
+     * Builds references used by a concept.
+     */
+    public void buildReferences() {
+    }
+
+    /**
      * {@inheritDoc}.
      */
     @Override
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxKeyInfo.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxKeyInfo.java
index 9b96d3398..bd3b18ec9 100644
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxKeyInfo.java
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxKeyInfo.java
@@ -22,14 +22,10 @@
 
 package org.onap.policy.apex.model.basicmodel.concepts;
 
+import com.google.gson.annotations.SerializedName;
 import java.util.List;
 import java.util.Random;
 import java.util.UUID;
-import javax.xml.bind.annotation.XmlAccessType;
-import javax.xml.bind.annotation.XmlAccessorType;
-import javax.xml.bind.annotation.XmlElement;
-import javax.xml.bind.annotation.XmlRootElement;
-import javax.xml.bind.annotation.XmlType;
 import org.apache.commons.lang3.StringUtils;
 import org.onap.policy.apex.model.basicmodel.concepts.AxValidationResult.ValidationResult;
 import org.onap.policy.common.utils.validation.Assertions;
@@ -41,16 +37,9 @@ import org.onap.policy.common.utils.validation.Assertions;
  * <p>Validation checks that all fields are defined and that the key is valid. It also observes that descriptions are
  * blank and warns if the UUID is a zero UUID.
  */
-
-@XmlAccessorType(XmlAccessType.FIELD)
-@XmlRootElement(name = "apexKeyInfo", namespace = "http://www.onap.org/policy/apex-pdp")
-@XmlType(name = "AxKeyInfo", namespace = "http://www.onap.org/policy/apex-pdp",
-        propOrder = { "key", "uuid", "description" })
-
 public class AxKeyInfo extends AxConcept {
     private static final long serialVersionUID = -4023935924068914308L;
 
-    private static final int MAX_DESCRIPTION_LENGTH_8192 = 8192;
     private static final int UUID_BYTE_LENGTH_16 = 16;
 
     /*
@@ -58,13 +47,11 @@ public class AxKeyInfo extends AxConcept {
      */
     private static final Random sharedRandom = new Random();    // NOSONAR
 
-    @XmlElement(name = "key", required = true)
     private AxArtifactKey key;
 
-    @XmlElement(name = "UUID", required = true)
+    @SerializedName("UUID")
     private UUID uuid;
 
-    @XmlElement(required = true)
     private String description;
 
     /**
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxKeyInformation.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxKeyInformation.java
index d1cc99a22..439b2960f 100644
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxKeyInformation.java
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxKeyInformation.java
@@ -30,11 +30,6 @@ import java.util.Set;
 import java.util.TreeMap;
 import java.util.TreeSet;
 import java.util.UUID;
-import javax.xml.bind.Unmarshaller;
-import javax.xml.bind.annotation.XmlAccessType;
-import javax.xml.bind.annotation.XmlAccessorType;
-import javax.xml.bind.annotation.XmlElement;
-import javax.xml.bind.annotation.XmlType;
 import org.onap.policy.apex.model.basicmodel.concepts.AxValidationResult.ValidationResult;
 import org.onap.policy.common.utils.validation.Assertions;
 
@@ -48,16 +43,10 @@ import org.onap.policy.common.utils.validation.Assertions;
  * the map is defined, that the key in each map entry matches the key if each entry value, and that no duplicate UUIDs
  * exist. Each key information entry is then validated individually.
  */
-@XmlAccessorType(XmlAccessType.FIELD)
-@XmlType(name = "AxKeyInformation", namespace = "http://www.onap.org/policy/apex-pdp",
-        propOrder = { "key", "keyInfoMap" })
-
 public class AxKeyInformation extends AxConcept implements AxConceptGetter<AxKeyInfo> {
     private static final long serialVersionUID = -2746380769017043888L;
 
-    @XmlElement(name = "key", required = true)
     private AxArtifactKey key;
-
     private Map<AxArtifactKey, AxKeyInfo> keyInfoMap;
 
     /**
@@ -102,22 +91,6 @@ public class AxKeyInformation extends AxConcept implements AxConceptGetter<AxKey
     }
 
     /**
-     * When a model is unmarshalled from disk or from the database, the key information map is returned as a raw Hash
-     * Map. This method is called by JAXB after unmarshaling and is used to convert the hash map to a
-     * {@link NavigableMap} so that it will work with the {@link AxConceptGetter} interface.
-     *
-     * @param unmarshaler the unmarshaler that is unmarshaling the model
-     * @param parent the parent object of this object in the unmarshaler
-     */
-    public void afterUnmarshal(final Unmarshaller unmarshaler, final Object parent) {
-        // The map must be navigable to allow name and version searching,
-        // unmarshaling returns a hash map
-        final NavigableMap<AxArtifactKey, AxKeyInfo> navigablekeyInfoMap = new TreeMap<>();
-        navigablekeyInfoMap.putAll(keyInfoMap);
-        keyInfoMap = navigablekeyInfoMap;
-    }
-
-    /**
      * This method generates default key information for all keys found in the concept passed in as a parameter that do
      * not already have key information.
      *
@@ -160,6 +133,14 @@ public class AxKeyInformation extends AxConcept implements AxConceptGetter<AxKey
     }
 
     /**
+     * {@inheritDoc}.
+     */
+    @Override
+    public void buildReferences() {
+        keyInfoMap.values().stream().forEach(keyInfo -> keyInfo.buildReferences());
+    }
+
+    /**
      * Sets the key of this concept.
      *
      * @param key the key of this concept
@@ -218,7 +199,7 @@ public class AxKeyInformation extends AxConcept implements AxConceptGetter<AxKey
     }
 
     /**
-     * Validate an key information entry.
+     * Validate a key information entry.
      *
      * @param keyInfoEntry the key information entry
      * @param uuidSet the set of UUIDs encountered in validation so far, the UUID of this entry is added to the set
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxModel.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxModel.java
index 5f63b9a3e..ce52b147f 100644
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxModel.java
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxModel.java
@@ -25,14 +25,7 @@ package org.onap.policy.apex.model.basicmodel.concepts;
 import java.util.List;
 import java.util.Set;
 import java.util.TreeSet;
-import javax.xml.bind.annotation.XmlAccessType;
-import javax.xml.bind.annotation.XmlAccessorType;
-import javax.xml.bind.annotation.XmlElement;
-import javax.xml.bind.annotation.XmlRootElement;
-import javax.xml.bind.annotation.XmlType;
-import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;
 import org.onap.policy.apex.model.basicmodel.concepts.AxValidationResult.ValidationResult;
-import org.onap.policy.apex.model.basicmodel.handling.KeyInfoMarshalFilter;
 import org.onap.policy.apex.model.basicmodel.service.ModelService;
 import org.onap.policy.common.utils.validation.Assertions;
 
@@ -47,25 +40,13 @@ import org.onap.policy.common.utils.validation.Assertions;
  * {@link AxArtifactKey} and {@link AxReferenceKey} usage references a key that exists. Finally, a check is made to
  * ensure that an {@link AxArtifactKey} instance exists for every {@link AxKeyInfo} instance.
  */
-
-@XmlRootElement(name = "apexModel", namespace = "http://www.onap.org/policy/apex-pdp")
-@XmlAccessorType(XmlAccessType.FIELD)
-@XmlType(name = "AxModel", namespace = "http://www.onap.org/policy/apex-pdp", propOrder =
-    { "key", "keyInformation" })
-
 public class AxModel extends AxConcept {
     private static final String IS_A_NULL_KEY = " is a null key";
 
     private static final long serialVersionUID = -771659065637205430L;
 
-    @XmlElement(name = "key", required = true)
     private AxArtifactKey key;
-
-    // @formatter:off
-    @XmlElement(name = "keyInformation", required = true)
-    @XmlJavaTypeAdapter(KeyInfoMarshalFilter.class)
     private AxKeyInformation keyInformation;
-    // @formatter:on
 
     /**
      * The Default Constructor creates this concept with a NULL artifact key.
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxReferenceKey.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxReferenceKey.java
index 6c671d3e6..b37bc47e4 100644
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxReferenceKey.java
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/AxReferenceKey.java
@@ -23,11 +23,6 @@ package org.onap.policy.apex.model.basicmodel.concepts;
 
 import java.util.ArrayList;
 import java.util.List;
-import javax.xml.bind.annotation.XmlAccessType;
-import javax.xml.bind.annotation.XmlAccessorType;
-import javax.xml.bind.annotation.XmlElement;
-import javax.xml.bind.annotation.XmlRootElement;
-import javax.xml.bind.annotation.XmlType;
 import org.onap.policy.apex.model.basicmodel.concepts.AxValidationResult.ValidationResult;
 import org.onap.policy.common.utils.validation.Assertions;
 
@@ -48,11 +43,6 @@ import org.onap.policy.common.utils.validation.Assertions;
  * VERSION_REGEXP regular expressions respectively and that the local name fields match the
  * LOCAL_NAME_REGEXP regular expression.
  */
-@XmlAccessorType(XmlAccessType.FIELD)
-@XmlRootElement(name = "apexReferenceKey", namespace = "http://www.onap.org/policy/apex-pdp")
-@XmlType(name = "AxReferenceKey", namespace = "http://www.onap.org/policy/apex-pdp", propOrder = { "parentKeyName",
-    "parentKeyVersion", "parentLocalName", "localName" })
-
 public class AxReferenceKey extends AxKey {
     private static final String PARENT_KEY_NAME = "parentKeyName";
     private static final String PARENT_KEY_VERSION = "parentKeyVersion";
@@ -61,28 +51,25 @@ public class AxReferenceKey extends AxKey {
 
     private static final long serialVersionUID = 8932717618579392561L;
 
-    /** Regular expression to specify the structure of local names in reference keys. */
+    /**
+     * Regular expression to specify the structure of local names in reference keys.
+     */
     public static final String LOCAL_NAME_REGEXP = "[A-Za-z0-9\\-_\\.]+|^$";
 
-    /** Regular expression to specify the structure of IDs in reference keys. */
+    /**
+     * Regular expression to specify the structure of IDs in reference keys.
+     */
     public static final String REFERENCE_KEY_ID_REGEXP =
-                    "[A-Za-z0-9\\-_]+:[0-9].[0-9].[0-9]:[A-Za-z0-9\\-_]+:[A-Za-z0-9\\-_]+";
+        "[A-Za-z0-9\\-_]+:[0-9].[0-9].[0-9]:[A-Za-z0-9\\-_]+:[A-Za-z0-9\\-_]+";
 
     private static final int PARENT_NAME_FIELD = 0;
     private static final int PARENT_VERSION_FIELD = 1;
     private static final int PARENT_LOCAL_NAME_FIELD = 2;
     private static final int LOCAL_NAME_FIELD = 3;
 
-    @XmlElement(required = true)
     private String parentKeyName;
-
-    @XmlElement(required = true)
     private String parentKeyVersion;
-
-    @XmlElement(required = true)
     private String parentLocalName;
-
-    @XmlElement(required = true)
     private String localName;
 
     /**
@@ -95,19 +82,17 @@ public class AxReferenceKey extends AxKey {
     /**
      * The Copy Constructor creates a key by copying another key.
      *
-     * @param referenceKey
-     *        the reference key to copy from
+     * @param referenceKey the reference key to copy from
      */
     public AxReferenceKey(final AxReferenceKey referenceKey) {
         this(referenceKey.getParentKeyName(), referenceKey.getParentKeyVersion(), referenceKey.getParentLocalName(),
-                        referenceKey.getLocalName());
+            referenceKey.getLocalName());
     }
 
     /**
      * Constructor to create a null reference key for the specified parent artifact key.
      *
-     * @param axArtifactKey
-     *        the parent artifact key of this reference key
+     * @param axArtifactKey the parent artifact key of this reference key
      */
     public AxReferenceKey(final AxArtifactKey axArtifactKey) {
         this(axArtifactKey.getName(), axArtifactKey.getVersion(), NULL_KEY_NAME, NULL_KEY_NAME);
@@ -116,10 +101,8 @@ public class AxReferenceKey extends AxKey {
     /**
      * Constructor to create a reference key for the given parent artifact key with the given local name.
      *
-     * @param axArtifactKey
-     *        the parent artifact key of this reference key
-     * @param localName
-     *        the local name of this reference key
+     * @param axArtifactKey the parent artifact key of this reference key
+     * @param localName     the local name of this reference key
      */
     public AxReferenceKey(final AxArtifactKey axArtifactKey, final String localName) {
         this(axArtifactKey, NULL_KEY_NAME, localName);
@@ -128,10 +111,8 @@ public class AxReferenceKey extends AxKey {
     /**
      * Constructor to create a reference key for the given parent reference key with the given local name.
      *
-     * @param parentReferenceKey
-     *        the parent reference key of this reference key
-     * @param localName
-     *        the local name of this reference key
+     * @param parentReferenceKey the parent reference key of this reference key
+     * @param localName          the local name of this reference key
      */
     public AxReferenceKey(final AxReferenceKey parentReferenceKey, final String localName) {
         this(parentReferenceKey.getParentArtifactKey(), parentReferenceKey.getLocalName(), localName);
@@ -141,12 +122,9 @@ public class AxReferenceKey extends AxKey {
      * Constructor to create a reference key for the given parent reference key (specified by the parent reference key's
      * artifact key and local name) with the given local name.
      *
-     * @param axArtifactKey
-     *        the artifact key of the parent reference key of this reference key
-     * @param parentLocalName
-     *        the local name of the parent reference key of this reference key
-     * @param localName
-     *        the local name of this reference key
+     * @param axArtifactKey   the artifact key of the parent reference key of this reference key
+     * @param parentLocalName the local name of the parent reference key of this reference key
+     * @param localName       the local name of this reference key
      */
     public AxReferenceKey(final AxArtifactKey axArtifactKey, final String parentLocalName, final String localName) {
         this(axArtifactKey.getName(), axArtifactKey.getVersion(), parentLocalName, localName);
@@ -156,12 +134,9 @@ public class AxReferenceKey extends AxKey {
      * Constructor to create a reference key for the given parent artifact key (specified by the parent artifact key's
      * name and version) with the given local name.
      *
-     * @param parentKeyName
-     *        the name of the parent artifact key of this reference key
-     * @param parentKeyVersion
-     *        the version of the parent artifact key of this reference key
-     * @param localName
-     *        the local name of this reference key
+     * @param parentKeyName    the name of the parent artifact key of this reference key
+     * @param parentKeyVersion the version of the parent artifact key of this reference key
+     * @param localName        the local name of this reference key
      */
     public AxReferenceKey(final String parentKeyName, final String parentKeyVersion, final String localName) {
         this(parentKeyName, parentKeyVersion, NULL_KEY_NAME, localName);
@@ -171,31 +146,26 @@ public class AxReferenceKey extends AxKey {
      * Constructor to create a reference key for the given parent key (specified by the parent key's name, version nad
      * local name) with the given local name.
      *
-     * @param parentKeyName
-     *        the parent key name of this reference key
-     * @param parentKeyVersion
-     *        the parent key version of this reference key
-     * @param parentLocalName
-     *        the parent local name of this reference key
-     * @param localName
-     *        the local name of this reference key
+     * @param parentKeyName    the parent key name of this reference key
+     * @param parentKeyVersion the parent key version of this reference key
+     * @param parentLocalName  the parent local name of this reference key
+     * @param localName        the local name of this reference key
      */
     public AxReferenceKey(final String parentKeyName, final String parentKeyVersion, final String parentLocalName,
-                    final String localName) {
+                          final String localName) {
         super();
         this.parentKeyName = Assertions.validateStringParameter(PARENT_KEY_NAME, parentKeyName, NAME_REGEXP);
         this.parentKeyVersion = Assertions.validateStringParameter(PARENT_KEY_VERSION, parentKeyVersion,
-                        VERSION_REGEXP);
+            VERSION_REGEXP);
         this.parentLocalName = Assertions.validateStringParameter(PARENT_LOCAL_NAME, parentLocalName,
-                        LOCAL_NAME_REGEXP);
+            LOCAL_NAME_REGEXP);
         this.localName = Assertions.validateStringParameter(LOCAL_NAME, localName, LOCAL_NAME_REGEXP);
     }
 
     /**
      * Constructor to create a key from the specified key ID.
      *
-     * @param id
-     *        the key ID in a format that respects the KEY_ID_REGEXP
+     * @param id the key ID in a format that respects the KEY_ID_REGEXP
      */
     public AxReferenceKey(final String id) {
         final var conditionedId = Assertions.validateStringParameter("id", id, REFERENCE_KEY_ID_REGEXP);
@@ -208,13 +178,13 @@ public class AxReferenceKey extends AxKey {
 
         // Initiate the new key
         parentKeyName = Assertions.validateStringParameter(PARENT_KEY_NAME, nameVersionNameArray[PARENT_NAME_FIELD],
-                        NAME_REGEXP);
+            NAME_REGEXP);
         parentKeyVersion = Assertions.validateStringParameter(PARENT_KEY_VERSION,
-                        nameVersionNameArray[PARENT_VERSION_FIELD], VERSION_REGEXP);
+            nameVersionNameArray[PARENT_VERSION_FIELD], VERSION_REGEXP);
         parentLocalName = Assertions.validateStringParameter(PARENT_LOCAL_NAME,
-                        nameVersionNameArray[PARENT_LOCAL_NAME_FIELD], LOCAL_NAME_REGEXP);
+            nameVersionNameArray[PARENT_LOCAL_NAME_FIELD], LOCAL_NAME_REGEXP);
         localName = Assertions.validateStringParameter(LOCAL_NAME, nameVersionNameArray[LOCAL_NAME_FIELD],
-                        LOCAL_NAME_REGEXP);
+            LOCAL_NAME_REGEXP);
     }
 
     /**
@@ -224,7 +194,7 @@ public class AxReferenceKey extends AxKey {
      */
     public static AxReferenceKey getNullKey() {
         return new AxReferenceKey(AxKey.NULL_KEY_NAME, AxKey.NULL_KEY_VERSION, AxKey.NULL_KEY_NAME,
-                        AxKey.NULL_KEY_NAME);
+            AxKey.NULL_KEY_NAME);
     }
 
     /**
@@ -274,8 +244,7 @@ public class AxReferenceKey extends AxKey {
     /**
      * Sets the parent artifact key of this reference key.
      *
-     * @param parentKey
-     *        the parent artifact key of this reference key
+     * @param parentKey the parent artifact key of this reference key
      */
     public void setParentArtifactKey(final AxArtifactKey parentKey) {
         Assertions.argumentNotNull(parentKey, "parentKey may not be null");
@@ -288,8 +257,7 @@ public class AxReferenceKey extends AxKey {
     /**
      * Sets the parent reference key of this reference key.
      *
-     * @param parentKey
-     *        the parent reference key of this reference key
+     * @param parentKey the parent reference key of this reference key
      */
     public void setParentReferenceKey(final AxReferenceKey parentKey) {
         Assertions.argumentNotNull(parentKey, "parentKey may not be null");
@@ -311,8 +279,7 @@ public class AxReferenceKey extends AxKey {
     /**
      * Sets the parent key name of this reference key.
      *
-     * @param parentKeyName
-     *        the parent key name of this reference key
+     * @param parentKeyName the parent key name of this reference key
      */
     public void setParentKeyName(final String parentKeyName) {
         this.parentKeyName = Assertions.validateStringParameter(PARENT_KEY_NAME, parentKeyName, NAME_REGEXP);
@@ -330,12 +297,11 @@ public class AxReferenceKey extends AxKey {
     /**
      * Sets the parent key version of this reference key.
      *
-     * @param parentKeyVersion
-     *        the parent key version of this reference key
+     * @param parentKeyVersion the parent key version of this reference key
      */
     public void setParentKeyVersion(final String parentKeyVersion) {
         this.parentKeyVersion = Assertions.validateStringParameter(PARENT_KEY_VERSION, parentKeyVersion,
-                        VERSION_REGEXP);
+            VERSION_REGEXP);
     }
 
     /**
@@ -350,12 +316,11 @@ public class AxReferenceKey extends AxKey {
     /**
      * Sets the parent local name of this reference key.
      *
-     * @param parentLocalName
-     *        the parent local name of this reference key
+     * @param parentLocalName the parent local name of this reference key
      */
     public void setParentLocalName(final String parentLocalName) {
         this.parentLocalName = Assertions.validateStringParameter(PARENT_LOCAL_NAME, parentLocalName,
-                        LOCAL_NAME_REGEXP);
+            LOCAL_NAME_REGEXP);
     }
 
     /**
@@ -370,8 +335,7 @@ public class AxReferenceKey extends AxKey {
     /**
      * Sets the local name of this reference key.
      *
-     * @param localName
-     *        the local name of this reference key
+     * @param localName the local name of this reference key
      */
     public void setLocalName(final String localName) {
         this.localName = Assertions.validateStringParameter(LOCAL_NAME, localName, LOCAL_NAME_REGEXP);
@@ -409,31 +373,31 @@ public class AxReferenceKey extends AxKey {
     @Override
     public AxValidationResult validate(final AxValidationResult result) {
         final var parentNameValidationErrorMessage = Assertions.getStringParameterValidationMessage(PARENT_KEY_NAME,
-                        parentKeyName, NAME_REGEXP);
+            parentKeyName, NAME_REGEXP);
         if (parentNameValidationErrorMessage != null) {
             result.addValidationMessage(new AxValidationMessage(this, this.getClass(), ValidationResult.INVALID,
-                            "parentKeyName invalid-" + parentNameValidationErrorMessage));
+                "parentKeyName invalid-" + parentNameValidationErrorMessage));
         }
 
         final var parentKeyVersionValidationErrorMessage = Assertions
-                        .getStringParameterValidationMessage(PARENT_KEY_VERSION, parentKeyVersion, VERSION_REGEXP);
+            .getStringParameterValidationMessage(PARENT_KEY_VERSION, parentKeyVersion, VERSION_REGEXP);
         if (parentKeyVersionValidationErrorMessage != null) {
             result.addValidationMessage(new AxValidationMessage(this, this.getClass(), ValidationResult.INVALID,
-                            "parentKeyVersion invalid-" + parentKeyVersionValidationErrorMessage));
+                "parentKeyVersion invalid-" + parentKeyVersionValidationErrorMessage));
         }
 
         final var parentLocalNameValidationErrorMessage = Assertions
-                        .getStringParameterValidationMessage(PARENT_LOCAL_NAME, parentLocalName, LOCAL_NAME_REGEXP);
+            .getStringParameterValidationMessage(PARENT_LOCAL_NAME, parentLocalName, LOCAL_NAME_REGEXP);
         if (parentLocalNameValidationErrorMessage != null) {
             result.addValidationMessage(new AxValidationMessage(this, this.getClass(), ValidationResult.INVALID,
-                            "parentLocalName invalid-" + parentLocalNameValidationErrorMessage));
+                "parentLocalName invalid-" + parentLocalNameValidationErrorMessage));
         }
 
         final var localNameValidationErrorMessage = Assertions.getStringParameterValidationMessage(LOCAL_NAME,
-                        localName, LOCAL_NAME_REGEXP);
+            localName, LOCAL_NAME_REGEXP);
         if (localNameValidationErrorMessage != null) {
             result.addValidationMessage(new AxValidationMessage(this, this.getClass(), ValidationResult.INVALID,
-                            "localName invalid-" + localNameValidationErrorMessage));
+                "localName invalid-" + localNameValidationErrorMessage));
         }
 
         return result;
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/package-info.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/package-info.java
index 294a66496..347e46a0f 100644
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/package-info.java
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/concepts/package-info.java
@@ -1,6 +1,7 @@
 /*-
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
+ *  Modifications Copyright (C) 2022 Nordix Foundation.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,12 +24,4 @@
  *
  * @author Liam Fallon (liam.fallon@ericsson.com)
  */
-
-@XmlSchema(namespace = "http://www.onap.org/policy/apex-pdp", elementFormDefault = XmlNsForm.QUALIFIED,
-        xmlns = { @XmlNs(namespaceURI = "http://www.onap.org/policy/apex-pdp", prefix = "") })
-
 package org.onap.policy.apex.model.basicmodel.concepts;
-
-import javax.xml.bind.annotation.XmlNs;
-import javax.xml.bind.annotation.XmlNsForm;
-import javax.xml.bind.annotation.XmlSchema;
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelCustomGsonMapAdapter.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelCustomGsonMapAdapter.java
new file mode 100644
index 000000000..cb67590f7
--- /dev/null
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelCustomGsonMapAdapter.java
@@ -0,0 +1,118 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2022 Nordix Foundation.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.apex.model.basicmodel.handling;
+
+import com.google.gson.JsonArray;
+import com.google.gson.JsonDeserializationContext;
+import com.google.gson.JsonDeserializer;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParseException;
+import com.google.gson.JsonSerializationContext;
+import com.google.gson.JsonSerializer;
+import java.lang.reflect.ParameterizedType;
+import java.lang.reflect.Type;
+import java.util.AbstractMap;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.TreeMap;
+import java.util.stream.Collectors;
+import java.util.stream.StreamSupport;
+
+@SuppressWarnings("rawtypes")
+public class ApexModelCustomGsonMapAdapter implements JsonSerializer<Map>, JsonDeserializer<Map> {
+    private static final String MAP_ENTRY_KEY = "entry";
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public Map deserialize(JsonElement jsonElement, Type typeOfT, JsonDeserializationContext context)
+        throws JsonParseException {
+
+        if (!(jsonElement instanceof JsonObject)) {
+            throw new JsonParseException("could not parse JSON map, map is not a JsonObject");
+        }
+
+        JsonObject jsonObject = (JsonObject) jsonElement;
+
+        if (jsonObject.size() != 1) {
+            throw new JsonParseException("could not parse JSON map, map must be in a JsonObject with a single member");
+        }
+
+        JsonArray mapEntryArray = (JsonArray) jsonObject.get(MAP_ENTRY_KEY);
+        if (mapEntryArray == null) {
+            throw new JsonParseException("could not parse JSON map, map \"entry\" in JsonObject not found");
+        }
+
+        return new TreeMap(
+            StreamSupport
+                .stream(mapEntryArray.spliterator(), true)
+                .map(element -> deserializeMapEntry(element, typeOfT, context))
+                .collect(Collectors.toMap(entry -> entry.getKey(), entry -> entry.getValue()))
+        );
+    }
+
+    @Override
+    public JsonElement serialize(Map sourceMap, Type typeOfSrc, JsonSerializationContext context) {
+
+        // A map is stored in a JsonArray
+        JsonArray mapEntryArray = new JsonArray();
+
+        for (Object mapEntryObject : sourceMap.entrySet()) {
+            Entry mapEntry = (Entry) mapEntryObject;
+            mapEntryArray.add(serializeMapEntry(mapEntry, typeOfSrc, context));
+        }
+
+        JsonObject returnObject = new JsonObject();
+        returnObject.add(MAP_ENTRY_KEY, mapEntryArray);
+
+        return returnObject;
+    }
+
+    @SuppressWarnings("unchecked")
+    private static Entry deserializeMapEntry(JsonElement element, Type typeOfT, JsonDeserializationContext context) {
+        // Get the types of the map
+        ParameterizedType pt = (ParameterizedType) typeOfT;
+
+        // Type of the key and value of the map
+        Type keyType = pt.getActualTypeArguments()[0];
+        Type valueType = pt.getActualTypeArguments()[1];
+
+        // Deserialize the key and value
+        return new AbstractMap.SimpleEntry(
+            context.deserialize(element.getAsJsonObject().get("key"), keyType),
+            context.deserialize(element.getAsJsonObject().get("value"), valueType));
+    }
+
+    private static JsonElement serializeMapEntry(Entry sourceEntry, Type typeOfSrc, JsonSerializationContext context) {
+        // Get the types of the map
+        ParameterizedType pt = (ParameterizedType) typeOfSrc;
+
+        // Type of the key and value of the map
+        Type keyType = pt.getActualTypeArguments()[0];
+        Type valueType = pt.getActualTypeArguments()[1];
+
+        JsonObject entryObject = new JsonObject();
+        entryObject.add("key", context.serialize(sourceEntry.getKey(), keyType));
+        entryObject.add("value", context.serialize(sourceEntry.getValue(), valueType));
+
+        return entryObject;
+    }
+}
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelCustomGsonRefereceKeyAdapter.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelCustomGsonRefereceKeyAdapter.java
new file mode 100644
index 000000000..d731c8689
--- /dev/null
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelCustomGsonRefereceKeyAdapter.java
@@ -0,0 +1,50 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2022 Nordix Foundation.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.apex.model.basicmodel.handling;
+
+import com.google.gson.JsonDeserializationContext;
+import com.google.gson.JsonDeserializer;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParseException;
+import java.lang.reflect.Type;
+import org.onap.policy.apex.model.basicmodel.concepts.AxReferenceKey;
+
+public class ApexModelCustomGsonRefereceKeyAdapter implements JsonDeserializer<AxReferenceKey> {
+
+    @Override
+    public AxReferenceKey deserialize(JsonElement jsonElement, Type typeOfT, JsonDeserializationContext context)
+        throws JsonParseException {
+
+        if (jsonElement instanceof JsonObject) {
+            return new AxReferenceKey(
+                jsonElement.getAsJsonObject().get("parentKeyName").getAsString(),
+                jsonElement.getAsJsonObject().get("parentKeyVersion").getAsString(),
+                jsonElement.getAsJsonObject().get("parentLocalName").getAsString(),
+                jsonElement.getAsJsonObject().get("localName").getAsString()
+            );
+        } else {
+            AxReferenceKey returnKey = new AxReferenceKey();
+            returnKey.setLocalName(jsonElement.getAsString());
+            return returnKey;
+        }
+    }
+}
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelFileWriter.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelFileWriter.java
index 908ad31aa..54b5651cc 100644
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelFileWriter.java
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelFileWriter.java
@@ -1,7 +1,7 @@
 /*
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- *  Modifications Copyright (C) 2021 Nordix Foundation.
+ *  Modifications Copyright (C) 2021-2022 Nordix Foundation.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,6 +23,8 @@ package org.onap.policy.apex.model.basicmodel.handling;
 
 import java.io.File;
 import java.io.FileOutputStream;
+import lombok.Getter;
+import lombok.Setter;
 import org.onap.policy.apex.model.basicmodel.concepts.ApexException;
 import org.onap.policy.apex.model.basicmodel.concepts.AxModel;
 import org.slf4j.ext.XLogger;
@@ -34,42 +36,21 @@ import org.slf4j.ext.XLoggerFactory;
  * @author Liam Fallon (liam.fallon@ericsson.com)
  * @param <M> the type of Apex model to write to file, must be a sub class of {@link AxModel}
  */
+@Getter
+@Setter
 public class ApexModelFileWriter<M extends AxModel> {
     private static final XLogger LOGGER = XLoggerFactory.getXLogger(ApexModelFileWriter.class);
 
     // Should models being written to files be valid
-    private boolean validateFlag;
+    private boolean validate;
 
     /**
      * Constructor, set the validation flag.
      *
-     * @param validateFlag indicates if validation be performed prior to output
+     * @param validate indicates if validation be performed prior to output
      */
-    public ApexModelFileWriter(final boolean validateFlag) {
-        this.validateFlag = validateFlag;
-    }
-
-    /**
-     * Write a model to an XML file.
-     *
-     * @param model The model to write
-     * @param rootModelClass The concept class
-     * @param modelFileName The name of the file to write to
-     * @throws ApexException thrown on errors
-     */
-    public void apexModelWriteXmlFile(final M model, final Class<M> rootModelClass, final String modelFileName)
-                    throws ApexException {
-        LOGGER.debug("running apexModelWriteXMLFile . . .");
-
-        final ApexModelWriter<M> modelWriter = new ApexModelWriter<>(rootModelClass);
-        modelWriter.setValidateFlag(validateFlag);
-        modelWriter.getCDataFieldSet().add("description");
-        modelWriter.getCDataFieldSet().add("logic");
-        modelWriter.getCDataFieldSet().add("uiLogic");
-
-        writeModelFile(model, modelWriter, modelFileName);
-
-        LOGGER.debug("ran apexModelWriteXMLFile");
+    public ApexModelFileWriter(final boolean validate) {
+        this.validate = validate;
     }
 
     /**
@@ -85,8 +66,7 @@ public class ApexModelFileWriter<M extends AxModel> {
         LOGGER.debug("running apexModelWriteJSONFile . . .");
 
         final ApexModelWriter<M> modelWriter = new ApexModelWriter<>(rootModelClass);
-        modelWriter.setJsonOutput(true);
-        modelWriter.setValidateFlag(validateFlag);
+        modelWriter.setValidate(validate);
 
         writeModelFile(model, modelWriter, modelFileName);
 
@@ -94,24 +74,6 @@ public class ApexModelFileWriter<M extends AxModel> {
     }
 
     /**
-     * Checks if the validation flag is set.
-     *
-     * @return true, the validation flag is set
-     */
-    public boolean isValidateFlag() {
-        return validateFlag;
-    }
-
-    /**
-     * Sets the validate flag.
-     *
-     * @param validateFlag the validate flag value
-     */
-    public void setValidateFlag(final boolean validateFlag) {
-        this.validateFlag = validateFlag;
-    }
-
-    /**
      * Write a model to a file using a model writer.
      *
      * @param model The model to write
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelReader.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelReader.java
index 7e136f6b3..a9bd2fe60 100644
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelReader.java
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelReader.java
@@ -1,7 +1,7 @@
 /*
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- *  Modifications Copyright (C) 2019-2021 Nordix Foundation.
+ *  Modifications Copyright (C) 2019-2022 Nordix Foundation.
  *  Modifications Copyright (C) 2021 AT&T Intellectual Property. All rights reserved.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -22,55 +22,47 @@
 
 package org.onap.policy.apex.model.basicmodel.handling;
 
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
 import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
-import java.io.StringReader;
-import java.util.regex.Pattern;
-import javax.xml.XMLConstants;
-import javax.xml.bind.JAXBElement;
-import javax.xml.bind.JAXBException;
-import javax.xml.bind.Unmarshaller;
-import javax.xml.transform.stream.StreamSource;
-import javax.xml.validation.SchemaFactory;
-import org.eclipse.persistence.jaxb.JAXBContextFactory;
-import org.eclipse.persistence.jaxb.MarshallerProperties;
-import org.eclipse.persistence.oxm.MediaType;
+import java.util.Map;
+import lombok.Getter;
+import lombok.Setter;
 import org.onap.policy.apex.model.basicmodel.concepts.AxConcept;
+import org.onap.policy.apex.model.basicmodel.concepts.AxReferenceKey;
 import org.onap.policy.apex.model.basicmodel.concepts.AxValidationResult;
-import org.onap.policy.common.utils.resources.ResourceUtils;
 import org.onap.policy.common.utils.resources.TextFileUtils;
 import org.onap.policy.common.utils.validation.Assertions;
 import org.slf4j.ext.XLogger;
 import org.slf4j.ext.XLoggerFactory;
 
 /**
- * This class reads an Apex concept from an XML file into a Java Apex Concept {@link AxConcept}.
+ * This class reads an Apex concept from a file into a Java Apex Concept {@link AxConcept}.
  *
  * @author Liam Fallon (liam.fallon@ericsson.com)
  * @param <C> the type of Apex concept to read, must be a sub class of {@link AxConcept}
  */
+@Getter
+@Setter
 public class ApexModelReader<C extends AxConcept> {
     // Get a reference to the logger
     private static final XLogger LOGGER = XLoggerFactory.getXLogger(ApexModelReader.class);
 
-    // Regular expressions for checking input types
-    // (starts with <?xml...>
-    private static final String XML_INPUT_TYPE_REGEXP = "^\\s*<\\?xml.*>\\s*";
-    // starts with some kind of bracket [ or (
-    private static final String JSON_INPUT_TYPE_REGEXP = "^\\s*[\\(\\{\\[][\\s\\S]*[\\)\\}\\]]";
-    // or {, then has something, then has
-    // and has a close bracket
+    // Use GSON to deserialize JSON
+    private static Gson gson = new GsonBuilder()
+        .registerTypeAdapter(AxReferenceKey.class, new ApexModelCustomGsonRefereceKeyAdapter())
+        .registerTypeAdapter(Map.class, new ApexModelCustomGsonMapAdapter())
+        .setPrettyPrinting()
+        .create();
 
     //  The root class of the concept we are reading
     private final Class<C> rootConceptClass;
 
-    // The unmarshaller for the Apex concepts
-    private Unmarshaller unmarshaller = null;
-
     // All read concepts are validated after reading if this flag is set
-    private boolean validateFlag = true;
+    private boolean validate = true;
 
     /**
      * Constructor, initiates the reader with validation on.
@@ -81,17 +73,6 @@ public class ApexModelReader<C extends AxConcept> {
     public ApexModelReader(final Class<C> rootConceptClass) throws ApexModelException {
         // Save the root concept class
         this.rootConceptClass = rootConceptClass;
-
-        try {
-            final var jaxbContext = JAXBContextFactory.createContext(new Class[] {rootConceptClass}, null);
-
-            // Set up the unmarshaller to carry out validation
-            unmarshaller = jaxbContext.createUnmarshaller();
-            unmarshaller.setEventHandler(new javax.xml.bind.helpers.DefaultValidationEventHandler());
-        } catch (final JAXBException e) {
-            LOGGER.error("Unable to set JAXB context", e);
-            throw new ApexModelException("Unable to set JAXB context", e);
-        }
     }
 
     /**
@@ -103,36 +84,11 @@ public class ApexModelReader<C extends AxConcept> {
      */
     public ApexModelReader(final Class<C> rootConceptClass, final boolean validate) throws ApexModelException {
         this(rootConceptClass);
-        this.validateFlag = validate;
-    }
-
-    /**
-     * Set the schema to use for reading XML files.
-     *
-     * @param schemaFileName the schema file to use
-     * @throws ApexModelException if the schema cannot be set
-     */
-    public void setSchema(final String schemaFileName) throws ApexModelException {
-        // Has a schema been set
-        if (schemaFileName != null) {
-            try {
-                // Set the concept schema
-                final var schemaUrl = ResourceUtils.getUrlResource(schemaFileName);
-                final var apexConceptSchema =
-                        SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI).newSchema(schemaUrl);
-                unmarshaller.setSchema(apexConceptSchema);
-            } catch (final Exception e) {
-                LOGGER.error("Unable to load schema ", e);
-                throw new ApexModelException("Unable to load schema", e);
-            }
-        } else {
-            // Clear the schema
-            unmarshaller.setSchema(null);
-        }
+        this.validate = validate;
     }
 
     /**
-     * This method checks the specified Apex concept XML file and reads it into an Apex concept.
+     * This method checks the specified Apex concept file and reads it into an Apex concept.
      *
      * @param apexConceptStream the apex concept stream
      * @return the Apex concept
@@ -179,28 +135,23 @@ public class ApexModelReader<C extends AxConcept> {
 
         LOGGER.entry("reading Apex concept from string . . .");
 
-        final var apexString = apexConceptString.trim();
-
-        // Set the type of input for this stream
-        setInputType(apexString);
-
-        // The Apex Concept
         C apexConcept = null;
-
-        // Use JAXB to read and verify the Apex concept XML file
         try {
-            // Load the configuration file
-            final var source = new StreamSource(new StringReader(apexString));
-            final JAXBElement<C> rootElement = unmarshaller.unmarshal(source, rootConceptClass);
-            apexConcept = rootElement.getValue();
-        } catch (final JAXBException e) {
-            throw new ApexModelException("Unable to unmarshal Apex concept ", e);
+            apexConcept = gson.fromJson(apexConceptString, rootConceptClass);
+        } catch (final Exception je) {
+            throw new ApexModelException("Unable to unmarshal Apex concept ", je);
+        }
+
+        if (apexConcept == null) {
+            throw new ApexModelException("Unable to unmarshal Apex concept, unmarshaled model is null ");
         }
 
         LOGGER.debug("reading of Apex concept {} completed");
 
+        apexConcept.buildReferences();
+
         // Check if the concept should be validated
-        if (validateFlag) {
+        if (validate) {
             // Validate the configuration file
             final AxValidationResult validationResult = apexConcept.validate(new AxValidationResult());
             if (validationResult.isValid()) {
@@ -215,54 +166,4 @@ public class ApexModelReader<C extends AxConcept> {
             return apexConcept;
         }
     }
-
-    /**
-     * Gets the value of the validation flag.
-     *
-     * @return the validation flag value
-     */
-    public boolean getValidateFlag() {
-        return validateFlag;
-    }
-
-    /**
-     * Sets the validation flag.
-     *
-     * @param validateFlag the validation flag value
-     */
-    public void setValidateFlag(final boolean validateFlag) {
-        this.validateFlag = validateFlag;
-    }
-
-    /**
-     * Set the type of input for the concept reader.
-     *
-     * @param apexConceptString The stream with
-     * @throws ApexModelException on errors setting input type
-     */
-    private void setInputType(final String apexConceptString) throws ApexModelException {
-        // Check the input type
-        if (Pattern.compile(JSON_INPUT_TYPE_REGEXP).matcher(apexConceptString).find()) {
-            // is json
-            try {
-                unmarshaller.setProperty(MarshallerProperties.MEDIA_TYPE, MediaType.APPLICATION_JSON);
-                unmarshaller.setProperty(MarshallerProperties.JSON_INCLUDE_ROOT, true);
-            } catch (final Exception e) {
-                LOGGER.warn("JAXB error setting marshaller for JSON Input", e);
-                throw new ApexModelException("JAXB error setting unmarshaller for JSON input", e);
-            }
-        } else if (Pattern.compile(XML_INPUT_TYPE_REGEXP).matcher(apexConceptString).find()) {
-            // is xml
-            try {
-                unmarshaller.setProperty(MarshallerProperties.MEDIA_TYPE, MediaType.APPLICATION_XML);
-            } catch (final Exception e) {
-                LOGGER.warn("JAXB error setting marshaller for XML Input", e);
-                throw new ApexModelException("JAXB error setting unmarshaller for XML input", e);
-            }
-        } else {
-            LOGGER.warn("format of input for Apex concept is neither JSON nor XML");
-            throw new ApexModelException("format of input for Apex concept is neither JSON nor XML");
-        }
-    }
-
 }
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelSaver.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelSaver.java
index dea32df49..79d69bdd5 100644
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelSaver.java
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelSaver.java
@@ -1,7 +1,7 @@
 /*
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- *  Modifications Copyright (C) 2019-2021 Nordix Foundation.
+ *  Modifications Copyright (C) 2019-2022 Nordix Foundation.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -29,7 +29,7 @@ import org.slf4j.ext.XLogger;
 import org.slf4j.ext.XLoggerFactory;
 
 /**
- * This class is used to save Apex models to file in XML or JSON format.
+ * This class is used to save Apex models to file in JSON format.
  *
  * @author Liam Fallon (liam.fallon@ericsson.com)
  * @param <M> the type of Apex model to save to file, must be a sub class of {@link AxModel}
@@ -51,7 +51,7 @@ public class ApexModelSaver<M extends AxModel> {
      * @param rootModelClass the class of the model, a sub class of {@link AxModel}
      * @param model the model to write, an instance of a sub class of {@link AxModel}
      * @param writePath the directory to which models will be written. The name of the written model will be the Model
-     *        Name for its key with the suffix {@code .xml} or {@code .json}.
+     *        Name for its key with the suffix {@code .json}.
      */
     public ApexModelSaver(final Class<M> rootModelClass, final M model, final String writePath) {
         Assertions.argumentNotNull(rootModelClass, "argument rootModelClass may not be null");
@@ -64,21 +64,6 @@ public class ApexModelSaver<M extends AxModel> {
     }
 
     /**
-     * Write an Apex model to a file in XML format. The model will be written to {@code <writePath/modelKeyName.xml>}
-     *
-     * @throws ApexException on errors writing the Apex model
-     */
-    public void apexModelWriteXml() throws ApexException {
-        LOGGER.debug("running apexModelWriteXML . . .");
-
-        // Write the file to disk
-        final var xmlFile = new File(writePath + File.separatorChar + model.getKey().getName() + ".xml");
-        new ApexModelFileWriter<M>(true).apexModelWriteXmlFile(model, rootModelClass, xmlFile.getPath());
-
-        LOGGER.debug("ran apexModelWriteXML");
-    }
-
-    /**
      * Write an Apex model to a file in JSON format. The model will be written to {@code <writePath/modelKeyName.json>}
      *
      * @throws ApexException on errors writing the Apex model
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelStringWriter.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelStringWriter.java
index de6a72ffd..a9df23afc 100644
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelStringWriter.java
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelStringWriter.java
@@ -1,7 +1,7 @@
 /*
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- *  Modifications Copyright (C) 2019-2021 Nordix Foundation.
+ *  Modifications Copyright (C) 2019-2022 Nordix Foundation.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -22,6 +22,8 @@
 package org.onap.policy.apex.model.basicmodel.handling;
 
 import java.io.ByteArrayOutputStream;
+import lombok.Getter;
+import lombok.Setter;
 import org.onap.policy.apex.model.basicmodel.concepts.ApexException;
 import org.onap.policy.apex.model.basicmodel.concepts.AxConcept;
 import org.onap.policy.common.utils.validation.Assertions;
@@ -34,19 +36,21 @@ import org.slf4j.ext.XLoggerFactory;
  * @author Liam Fallon (liam.fallon@ericsson.com)
  * @param <C> the type of Apex concept to write to a string, must be a sub class of {@link AxConcept}
  */
+@Getter
+@Setter
 public class ApexModelStringWriter<C extends AxConcept> {
     private static final XLogger LOGGER = XLoggerFactory.getXLogger(ApexModelStringWriter.class);
 
     // Should concepts being written to files be valid
-    private boolean validateFlag;
+    private boolean validate;
 
     /**
      * Constructor, set the validation flag.
      *
-     * @param validateFlag Should validation be performed prior to output
+     * @param validate Should validation be performed prior to output
      */
-    public ApexModelStringWriter(final boolean validateFlag) {
-        this.validateFlag = validateFlag;
+    public ApexModelStringWriter(final boolean validate) {
+        this.validate = validate;
     }
 
     /**
@@ -54,46 +58,14 @@ public class ApexModelStringWriter<C extends AxConcept> {
      *
      * @param concept The concept to write
      * @param rootConceptClass The concept class
-     * @param jsonFlag writes JSON if true, and a generic string if false
      * @return The string with the concept
      * @throws ApexException thrown on errors
      */
-    public String writeString(final C concept, final Class<C> rootConceptClass, final boolean jsonFlag)
+    public String writeString(final C concept, final Class<C> rootConceptClass)
                     throws ApexException {
         Assertions.argumentNotNull(concept, "concept may not be null");
 
-        if (jsonFlag) {
-            return writeJsonString(concept, rootConceptClass);
-        } else {
-            return concept.toString();
-        }
-    }
-
-    /**
-     * Write a concept to an XML string.
-     *
-     * @param concept The concept to write
-     * @param rootConceptClass The concept class
-     * @return The string with the concept
-     * @throws ApexException thrown on errors
-     */
-    public String writeXmlString(final C concept, final Class<C> rootConceptClass) throws ApexException {
-        LOGGER.debug("running writeXMLString . . .");
-
-        final ApexModelWriter<C> conceptWriter = new ApexModelWriter<>(rootConceptClass);
-        conceptWriter.setValidateFlag(validateFlag);
-        conceptWriter.getCDataFieldSet().add("description");
-        conceptWriter.getCDataFieldSet().add("logic");
-        conceptWriter.getCDataFieldSet().add("uiLogic");
-
-        try (var baOutputStream = new ByteArrayOutputStream()) {
-            conceptWriter.write(concept, baOutputStream);
-            return baOutputStream.toString();
-        } catch (final Exception e) {
-            LOGGER.warn("error writing XML string", e);
-            throw new ApexException("error writing XML string", e);
-        }
-
+        return writeJsonString(concept, rootConceptClass);
     }
 
     /**
@@ -108,8 +80,7 @@ public class ApexModelStringWriter<C extends AxConcept> {
         LOGGER.debug("running writeJSONString . . .");
 
         final ApexModelWriter<C> conceptWriter = new ApexModelWriter<>(rootConceptClass);
-        conceptWriter.setJsonOutput(true);
-        conceptWriter.setValidateFlag(validateFlag);
+        conceptWriter.setValidate(validate);
 
         try (var baOutputStream = new ByteArrayOutputStream()) {
             conceptWriter.write(concept, baOutputStream);
@@ -120,22 +91,4 @@ public class ApexModelStringWriter<C extends AxConcept> {
         }
 
     }
-
-    /**
-     * Checks if is validate flag.
-     *
-     * @return true, if checks if is validate flag
-     */
-    public boolean isValidateFlag() {
-        return validateFlag;
-    }
-
-    /**
-     * Sets the validate flag.
-     *
-     * @param validateFlag the validate flag
-     */
-    public void setValidateFlag(final boolean validateFlag) {
-        this.validateFlag = validateFlag;
-    }
 }
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelWriter.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelWriter.java
index 9e43f76bd..349622697 100644
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelWriter.java
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelWriter.java
@@ -1,7 +1,7 @@
 /*-
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- *  Modifications Copyright (C) 2019-2021 Nordix Foundation.
+ *  Modifications Copyright (C) 2019-2022 Nordix Foundation.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,129 +21,67 @@
 
 package org.onap.policy.apex.model.basicmodel.handling;
 
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import java.io.IOException;
 import java.io.OutputStream;
 import java.io.OutputStreamWriter;
 import java.io.Writer;
-import java.util.Set;
-import java.util.TreeSet;
-import javax.xml.XMLConstants;
-import javax.xml.bind.JAXBException;
-import javax.xml.bind.Marshaller;
-import javax.xml.parsers.DocumentBuilderFactory;
-import javax.xml.parsers.ParserConfigurationException;
-import javax.xml.transform.OutputKeys;
-import javax.xml.transform.Transformer;
-import javax.xml.transform.TransformerConfigurationException;
-import javax.xml.transform.TransformerException;
-import javax.xml.transform.TransformerFactory;
-import javax.xml.transform.dom.DOMSource;
-import javax.xml.transform.stream.StreamResult;
-import org.eclipse.persistence.jaxb.JAXBContextFactory;
-import org.eclipse.persistence.jaxb.MarshallerProperties;
-import org.eclipse.persistence.oxm.MediaType;
+import java.util.Map;
+import lombok.Getter;
+import lombok.Setter;
 import org.onap.policy.apex.model.basicmodel.concepts.AxConcept;
+import org.onap.policy.apex.model.basicmodel.concepts.AxReferenceKey;
 import org.onap.policy.apex.model.basicmodel.concepts.AxValidationResult;
 import org.onap.policy.common.utils.validation.Assertions;
 import org.slf4j.ext.XLogger;
 import org.slf4j.ext.XLoggerFactory;
 
 /**
- * This class writes an Apex concept to an XML file or JSON file from a Java Apex Concept.
+ * This class writes an Apex concept to a file from a Java Apex Concept.
  *
  * @param <C> the type of Apex concept to write, must be a sub class of {@link AxConcept}
  * @author John Keeney (john.keeney@ericsson.com)
  */
+@Getter
+@Setter
 public class ApexModelWriter<C extends AxConcept> {
 
     private static final String CONCEPT_MAY_NOT_BE_NULL = "concept may not be null";
     private static final String CONCEPT_WRITER_MAY_NOT_BE_NULL = "concept writer may not be null";
     private static final String CONCEPT_STREAM_MAY_NOT_BE_NULL = "concept stream may not be null";
 
+    // Use GSON to serialize JSON
+    private static Gson gson = new GsonBuilder()
+        .registerTypeAdapter(AxReferenceKey.class, new ApexModelCustomGsonRefereceKeyAdapter())
+        .registerTypeAdapter(Map.class, new ApexModelCustomGsonMapAdapter())
+        .setPrettyPrinting()
+        .create();
+
     // Get a reference to the logger
     private static final XLogger LOGGER = XLoggerFactory.getXLogger(ApexModelWriter.class);
 
-    // Writing as JSON or XML
-    private boolean jsonOutput = false;
-
-    // The list of fields to output as CDATA
-    private final Set<String> cdataFieldSet = new TreeSet<>();
-
-    // The Marshaller for the Apex concepts
-    private Marshaller marshaller = null;
+    //  The root class of the concept we are reading
+    private final Class<C> rootConceptClass;
 
     // All written concepts are validated before writing if this flag is set
-    private boolean validateFlag = true;
+    private boolean validate = true;
 
     /**
-     * Constructor, initiates the writer.
+     * Constructor, initiates the writer with validation on.
      *
      * @param rootConceptClass the root concept class for concept reading
-     * @throws ApexModelException the apex concept writer exception
+     * @throws ApexModelException the apex concept reader exception
      */
     public ApexModelWriter(final Class<C> rootConceptClass) throws ApexModelException {
-        // Set up Eclipselink for XML and JSON output
-        System.setProperty("javax.xml.bind.context.factory", "org.eclipse.persistence.jaxb.JAXBContextFactory");
-
-        try {
-            final var jaxbContext = JAXBContextFactory.createContext(new Class[]{rootConceptClass}, null);
-
-            // Set up the unmarshaller to carry out validation
-            marshaller = jaxbContext.createMarshaller();
-            marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
-            marshaller.setEventHandler(new javax.xml.bind.helpers.DefaultValidationEventHandler());
-        } catch (final JAXBException e) {
-            throw new ApexModelException("JAXB marshaller creation exception", e);
-        }
-    }
-
-    /**
-     * The set of fields to be output as CDATA.
-     *
-     * @return the set of fields
-     */
-    public Set<String> getCDataFieldSet() {
-        return cdataFieldSet;
-    }
-
-    /**
-     * Return true if JSON output enabled, XML output if false.
-     *
-     * @return true for JSON output
-     */
-    public boolean isJsonOutput() {
-        return jsonOutput;
-    }
-
-    /**
-     * Set the value of JSON output, true for JSON output, false for XML output.
-     *
-     * @param jsonOutput true for JSON output
-     * @throws ApexModelException on errors setting output type
-     */
-    public void setJsonOutput(final boolean jsonOutput) throws ApexModelException {
-        this.jsonOutput = jsonOutput;
-
-        // Set up output specific parameters
-        if (this.jsonOutput) {
-            try {
-                marshaller.setProperty(MarshallerProperties.MEDIA_TYPE, MediaType.APPLICATION_JSON);
-                marshaller.setProperty(MarshallerProperties.JSON_INCLUDE_ROOT, true);
-            } catch (final Exception e) {
-                throw new ApexModelException("JAXB error setting marshaller for JSON output", e);
-            }
-        } else {
-            try {
-                marshaller.setProperty(MarshallerProperties.MEDIA_TYPE, MediaType.APPLICATION_XML);
-            } catch (final Exception e) {
-                throw new ApexModelException("JAXB error setting marshaller for XML output", e);
-            }
-        }
+        // Save the root concept class
+        this.rootConceptClass = rootConceptClass;
     }
 
     /**
      * This method validates the Apex concept then writes it into a stream.
      *
-     * @param concept           the concept to write
+     * @param concept the concept to write
      * @param apexConceptStream the stream to write to
      * @throws ApexModelException on validation or writing exceptions
      */
@@ -157,7 +95,7 @@ public class ApexModelWriter<C extends AxConcept> {
     /**
      * This method validates the Apex concept then writes it into a writer.
      *
-     * @param concept           the concept to write
+     * @param concept the concept to write
      * @param apexConceptWriter the writer to write to
      * @throws ApexModelException on validation or writing exceptions
      */
@@ -166,84 +104,23 @@ public class ApexModelWriter<C extends AxConcept> {
         Assertions.argumentNotNull(apexConceptWriter, CONCEPT_WRITER_MAY_NOT_BE_NULL);
 
         // Check if we should validate the concept
-        if (validateFlag) {
+        if (validate) {
             // Validate the concept first
             final AxValidationResult validationResult = concept.validate(new AxValidationResult());
             if (!validationResult.isValid()) {
                 String message =
-                    "Apex concept xml (" + concept.getKey().getId() + ") validation failed: " + validationResult
-                        .toString();
+                    "Apex concept (" + concept.getKey().getId() + ") validation failed: " + validationResult.toString();
                 throw new ApexModelException(message);
             }
         }
 
-        if (jsonOutput) {
-            writeJson(concept, apexConceptWriter);
-        } else {
-            writeXml(concept, apexConceptWriter);
-        }
-    }
-
-    /**
-     * This method writes the Apex concept into a writer in XML format.
-     *
-     * @param concept           the concept to write
-     * @param apexConceptWriter the writer to write to
-     * @throws ApexModelException on validation or writing exceptions
-     */
-    private void writeXml(final C concept, final Writer apexConceptWriter) throws ApexModelException {
-        Assertions.argumentNotNull(concept, CONCEPT_MAY_NOT_BE_NULL);
-
-        LOGGER.debug("writing Apex concept XML . . .");
-
-        try {
-            // Write the concept into a DOM document, then transform to add CDATA fields and pretty
-            // print, then write out the result
-            final var docBuilderFactory = DocumentBuilderFactory.newInstance();
-            docBuilderFactory.setAttribute(XMLConstants.ACCESS_EXTERNAL_DTD, "");
-            docBuilderFactory.setAttribute(XMLConstants.ACCESS_EXTERNAL_SCHEMA, "");
-
-            docBuilderFactory.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);
-            final var document = docBuilderFactory.newDocumentBuilder().newDocument();
-
-            // Marshal the concept into the empty document.
-            marshaller.marshal(concept, document);
-
-            final var domTransformer = getTransformer();
-
-            // Convert the cDataFieldSet into a space delimited string
-            domTransformer.setOutputProperty(OutputKeys.CDATA_SECTION_ELEMENTS,
-                cdataFieldSet.toString().replaceAll("[\\[\\]\\,]", " "));
-            domTransformer.transform(new DOMSource(document), new StreamResult(apexConceptWriter));
-        } catch (JAXBException | TransformerException | ParserConfigurationException e) {
-            throw new ApexModelException("Unable to marshal Apex concept to XML", e);
-        }
-        LOGGER.debug("wrote Apex concept XML");
-    }
-
-    private Transformer getTransformer() throws TransformerConfigurationException {
-        // Transform the DOM to the output stream
-        final var transformerFactory = TransformerFactory.newInstance();
-        transformerFactory.setAttribute(XMLConstants.ACCESS_EXTERNAL_DTD, "");
-        transformerFactory.setAttribute(XMLConstants.ACCESS_EXTERNAL_STYLESHEET, "");
-
-        final var domTransformer = transformerFactory.newTransformer();
-
-        // Pretty print
-        try {
-            domTransformer.setOutputProperty(OutputKeys.INDENT, "yes");
-            // May fail if not using XALAN XSLT engine. But not in any way vital
-            domTransformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "2");
-        } catch (final Exception ignore) {
-            LOGGER.trace("Unable to set indent property", ignore);
-        }
-        return domTransformer;
+        writeJson(concept, apexConceptWriter);
     }
 
     /**
      * This method writes the Apex concept into a writer in JSON format.
      *
-     * @param concept           the concept to write
+     * @param concept the concept to write
      * @param apexConceptWriter the writer to write to
      * @throws ApexModelException on validation or writing exceptions
      */
@@ -252,29 +129,20 @@ public class ApexModelWriter<C extends AxConcept> {
 
         LOGGER.debug("writing Apex concept JSON . . .");
 
+        String modelJsonString = null;
         try {
-            marshaller.marshal(concept, apexConceptWriter);
-        } catch (final JAXBException e) {
-            throw new ApexModelException("Unable to marshal Apex concept to JSON", e);
+            modelJsonString = gson.toJson(concept, rootConceptClass);
+        } catch (Exception je) {
+            throw new ApexModelException("Unable to marshal Apex concept to JSON", je);
         }
-        LOGGER.debug("wrote Apex concept JSON");
-    }
 
-    /**
-     * Gets the validation flag value.
-     *
-     * @return the validation flag value
-     */
-    public boolean getValidateFlag() {
-        return validateFlag;
-    }
+        try {
+            apexConceptWriter.write(modelJsonString);
+            apexConceptWriter.close();
+        } catch (IOException ioe) {
+            throw new ApexModelException("Unable to write Apex concept as JSON", ioe);
+        }
 
-    /**
-     * Sets the validation flag.
-     *
-     * @param validateFlag the validation flag value
-     */
-    public void setValidateFlag(final boolean validateFlag) {
-        this.validateFlag = validateFlag;
+        LOGGER.debug("wrote Apex concept JSON");
     }
 }
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexSchemaGenerator.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexSchemaGenerator.java
deleted file mode 100644
index d5f34785b..000000000
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/ApexSchemaGenerator.java
+++ /dev/null
@@ -1,161 +0,0 @@
-/*
- * ============LICENSE_START=======================================================
- *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- *  Modifications Copyright (C) 2020-2021 Nordix Foundation.
- * ================================================================================
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- * SPDX-License-Identifier: Apache-2.0
- * ============LICENSE_END=========================================================
- */
-
-package org.onap.policy.apex.model.basicmodel.handling;
-
-import java.io.File;
-import java.io.IOException;
-import java.io.PrintStream;
-import java.io.StringWriter;
-import javax.xml.bind.JAXBContext;
-import javax.xml.bind.JAXBException;
-import javax.xml.bind.SchemaOutputResolver;
-import javax.xml.transform.Result;
-import javax.xml.transform.stream.StreamResult;
-import org.slf4j.ext.XLogger;
-import org.slf4j.ext.XLoggerFactory;
-
-/**
- * This class generates the XML model schema from the given Apex concept classes.
- *
- * @author Liam Fallon (liam.fallon@ericsson.com)
- */
-public class ApexSchemaGenerator {
-    // Get a reference to the logger
-    private static final XLogger LOGGER = XLoggerFactory.getXLogger(ApexSchemaGenerator.class);
-
-    /**
-     * A Main method to allow schema generation from the command line or from maven or scripts.
-     *
-     * @param args the command line arguments, usage is {@code ApexSchemaGenerator apex-root-class [schema-file-name]}
-     */
-    public static void main(final String[] args) {
-        PrintStream printStream = null;
-
-        if (args.length == 1) {
-            printStream = System.out;
-        } else if (args.length == 2) {
-            final var schemaFile = new File(args[1]);
-
-            try {
-                schemaFile.getParentFile().mkdirs();
-                printStream = new PrintStream(schemaFile);
-            } catch (final Exception e) {
-                LOGGER.error("error on Apex schema output", e);
-                return;
-            }
-        } else {
-            LOGGER.error("usage: ApexSchemaGenerator apex-root-class [schema-file-name]");
-            return;
-        }
-
-        // Get the schema
-        final String schema = new ApexSchemaGenerator().generate(args[0]);
-
-        // Output the schema
-        printStream.println(schema);
-
-        printStream.close();
-    }
-
-    /**
-     * Generates the XML schema (XSD) for the Apex model described using JAXB annotations.
-     *
-     * @param rootClassName the name of the root class for schema generation
-     * @return The schema
-     */
-    public String generate(final String rootClassName) {
-        JAXBContext jaxbContext;
-        try {
-            jaxbContext = JAXBContext.newInstance(Class.forName(rootClassName));
-        } catch (final ClassNotFoundException e) {
-            LOGGER.error("could not create JAXB context, root class " + rootClassName + " not found", e);
-            return null;
-        } catch (final JAXBException e) {
-            LOGGER.error("could not create JAXB context", e);
-            return null;
-        }
-
-        final var sor = new ApexSchemaOutputResolver();
-        try {
-            jaxbContext.generateSchema(sor);
-        } catch (final IOException e) {
-            LOGGER.error("error generating the Apex schema (XSD) file", e);
-            return null;
-        }
-
-        var schemaString = sor.getSchema();
-        schemaString = fixForUnqualifiedBug(schemaString);
-
-        return schemaString;
-    }
-
-    /**
-     * There is a bug in schema generation that does not specify the elements from Java Maps as being unqualified. This
-     * method "hacks" those elements in the schema to fix this, the elements being {@code entry}, {@code key}, and
-     * {@code value}
-     *
-     * @param schemaString The schema in which elements should be fixed
-     * @return the string
-     */
-    private String fixForUnqualifiedBug(final String schemaString) {
-        // Fix the "entry" element
-        var newSchemaString = schemaString.replace(
-                        "<xs:element name=\"entry\" minOccurs=\"0\" maxOccurs=\"unbounded\">",
-                        "<xs:element name=\"entry\" minOccurs=\"0\" maxOccurs=\"unbounded\" form=\"unqualified\">");
-
-        // Fix the "key" element
-        newSchemaString = newSchemaString.replace("<xs:element name=\"key\"",
-                        "<xs:element name=\"key\" form=\"unqualified\"");
-
-        // Fix the "value" element
-        newSchemaString = newSchemaString.replace("<xs:element name=\"value\"",
-                        "<xs:element name=\"value\" form=\"unqualified\"");
-
-        return newSchemaString;
-    }
-
-    /**
-     * This inner class is used to receive the output of schema generation from the JAXB schema generator.
-     */
-    private class ApexSchemaOutputResolver extends SchemaOutputResolver {
-        private final StringWriter stringWriter = new StringWriter();
-
-        /**
-         * {@inheritDoc}.
-         */
-        @Override
-        public Result createOutput(final String namespaceUri, final String suggestedFileName) throws IOException {
-            final var result = new StreamResult(stringWriter);
-            result.setSystemId(suggestedFileName);
-            return result;
-        }
-
-        /**
-         * Get the schema from the string writer.
-         *
-         * @return the schema generated by JAXB
-         */
-        public String getSchema() {
-            return stringWriter.toString();
-        }
-    }
-}
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/KeyInfoMarshalFilter.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/KeyInfoMarshalFilter.java
deleted file mode 100644
index cfc385d01..000000000
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/KeyInfoMarshalFilter.java
+++ /dev/null
@@ -1,104 +0,0 @@
-/*-
- * ============LICENSE_START=======================================================
- * Copyright (C) 2019 Nordix Foundation.
- * ================================================================================
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- * SPDX-License-Identifier: Apache-2.0
- * ============LICENSE_END=========================================================
- */
-
-package org.onap.policy.apex.model.basicmodel.handling;
-
-import java.util.Collection;
-import java.util.LinkedList;
-import java.util.List;
-import java.util.Map;
-import java.util.TreeMap;
-import javax.xml.bind.annotation.adapters.XmlAdapter;
-import org.onap.policy.apex.model.basicmodel.concepts.AxArtifactKey;
-import org.onap.policy.apex.model.basicmodel.concepts.AxKey;
-import org.onap.policy.apex.model.basicmodel.concepts.AxKeyInfo;
-import org.onap.policy.apex.model.basicmodel.concepts.AxKeyInformation;
-
-/**
- * This class implements a filter to prevent some keyinfo information being marshalled when a model is serialised.
- */
-public class KeyInfoMarshalFilter extends XmlAdapter<AxKeyInformation, AxKeyInformation> {
-
-    private List<AxKey> filterList = new LinkedList<>();
-
-    /**
-     * Adds a key to the list to be filtered.
-     *
-     * @param key the key to add to the filter list
-     */
-    public void addFilterKey(AxKey key) {
-        filterList.add(key);
-    }
-
-    /**
-     * Remove a key from the list to be filtered.
-     *
-     * @param key the key to remove from the filter list
-     * @return true if the passed key was in the filter list and has been removed.
-     */
-    public boolean removeFilterKey(AxKey key) {
-        return filterList.remove(key);
-    }
-
-    /**
-     * Adds some keys to the list to be filtered.
-     *
-     * @param keys the keys to add to the filter list
-     */
-    public void addFilterKeys(Collection<? extends AxKey> keys) {
-        filterList.addAll(keys);
-    }
-
-    /**
-     * Decide whether to unmarshall some keyinfos - Always.
-     *
-     * @param val the keyinfo
-     * @return the keyinfo
-     * @throws Exception if there is some problem unmarshalling
-     * @see javax.xml.bind.annotation.adapters.XmlAdapter#unmarshal(Object)
-     */
-    @Override
-    public AxKeyInformation unmarshal(AxKeyInformation val) throws Exception {
-        return val;
-    }
-
-    /**
-     * Select which keyinfo entries will be marshalled - i.e. those not in the filter list.
-     *
-     * @param val the keyinfo
-     * @return the keyinfo
-     * @throws Exception if there is some problem with the marshalling
-     * @see javax.xml.bind.annotation.adapters.XmlAdapter#marshal(Object)
-     */
-    @Override
-    public AxKeyInformation marshal(AxKeyInformation val) throws Exception {
-        if (val == null || val.getKeyInfoMap() == null || val.getKeyInfoMap().isEmpty() || filterList.isEmpty()) {
-            return val;
-        }
-        //create a new keyinfo clone to avoid removing keyinfo entries from the original model
-        AxKeyInformation ret = new AxKeyInformation(val);
-        Map<AxArtifactKey, AxKeyInfo> retmap = new TreeMap<>(ret.getKeyInfoMap());
-        for (AxKey key : filterList) {
-            retmap.remove(key);
-        }
-        ret.setKeyInfoMap(retmap);
-        return ret;
-    }
-}
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/package-info.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/package-info.java
index 081cff540..3d6dab3b2 100644
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/package-info.java
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/handling/package-info.java
@@ -1,6 +1,7 @@
 /*-
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
+ *  Modifications Copyright (C) 2022 Nordix Foundation.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,20 +18,4 @@
  * SPDX-License-Identifier: Apache-2.0
  * ============LICENSE_END=========================================================
  */
-
-/**
- * Contains a number of utility classes for handling APEX {@link org.onap.policy.apex.model.basicmodel.concepts.AxModel}
- * models and {@link org.onap.policy.apex.model.basicmodel.concepts.AxConcept} concepts. Classes to read and write
- * models to files, strings, and databases are included, as well as classes to generate XML schemas for models.
- *
- * @author Liam Fallon (liam.fallon@ericsson.com)
- */
-
-@XmlSchema(namespace = "http://www.onap.org/policy/apex-pdp", elementFormDefault = XmlNsForm.QUALIFIED,
-        xmlns = { @XmlNs(namespaceURI = "http://www.onap.org/policy/apex-pdp", prefix = "") })
-
 package org.onap.policy.apex.model.basicmodel.handling;
-
-import javax.xml.bind.annotation.XmlNs;
-import javax.xml.bind.annotation.XmlNsForm;
-import javax.xml.bind.annotation.XmlSchema;
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/package-info.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/package-info.java
index e540646d9..8ad405e25 100644
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/package-info.java
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/package-info.java
@@ -1,7 +1,7 @@
 /*
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- *  Modifications Copyright (C) 2019 Nordix Foundation.
+ *  Modifications Copyright (C) 2019,2022 Nordix Foundation.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -24,7 +24,7 @@
  * the model for APEX concepts anywhere in the system.
  *
  * <p>It also provides handling support to models, allowing them to be read and written to file and databases in JSON
- * and XML format.
+ * format.
  *
  * @author Liam Fallon (liam.fallon@ericsson.com)
  */
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/test/TestApexModel.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/test/TestApexModel.java
index 5dbf69492..9dde47d05 100644
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/test/TestApexModel.java
+++ b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/test/TestApexModel.java
@@ -44,7 +44,7 @@ import org.slf4j.ext.XLoggerFactory;
 public class TestApexModel<M extends AxModel> {
     private static final String MODEL_IS_INVALID = "model is invalid ";
     private static final String ERROR_PROCESSING_FILE = "error processing file ";
-    private static final String TEST_MODEL_UNEQUAL_STR = "test model does not equal model read from XML file ";
+    private static final String TEST_MODEL_UNEQUAL_STR = "test model does not equal model read from file ";
     private static final String TEMP_FILE_CREATE_ERR_STR = "error creating temporary file for Apex model";
 
     private static final XLogger LOGGER = XLoggerFactory.getXLogger(TestApexModel.class);
@@ -77,55 +77,6 @@ public class TestApexModel<M extends AxModel> {
     }
 
     /**
-     * Test write and read in XML format.
-     *
-     * @throws ApexException on write/read errors
-     */
-    public final void testApexModelWriteReadXml() throws ApexException {
-        LOGGER.debug("running testApexModelWriteReadXML . . .");
-
-        final var model = modelCreator.getModel();
-
-        // Write the file to disk
-        File xmlFile;
-
-        try {
-            xmlFile = File.createTempFile("ApexModel", ".xml");
-            xmlFile.deleteOnExit();
-        } catch (final Exception e) {
-            LOGGER.warn(TEMP_FILE_CREATE_ERR_STR, e);
-            throw new ApexException(TEMP_FILE_CREATE_ERR_STR, e);
-        }
-        new ApexModelFileWriter<M>(true).apexModelWriteXmlFile(model, rootModelClass, xmlFile.getPath());
-
-        // Read the file from disk
-        final ApexModelReader<M> modelReader = new ApexModelReader<>(rootModelClass);
-
-        try {
-            final var apexModelUrl = ResourceUtils.getLocalFile(xmlFile.getAbsolutePath());
-            final var fileModel = modelReader.read(apexModelUrl.openStream());
-            checkModelEquality(model, fileModel, TEST_MODEL_UNEQUAL_STR + xmlFile.getAbsolutePath());
-        } catch (final Exception e) {
-            LOGGER.warn(ERROR_PROCESSING_FILE + xmlFile.getAbsolutePath(), e);
-            throw new ApexException(ERROR_PROCESSING_FILE + xmlFile.getAbsolutePath(), e);
-        }
-
-        final ApexModelWriter<M> modelWriter = new ApexModelWriter<>(rootModelClass);
-        modelWriter.getCDataFieldSet().add("description");
-        modelWriter.getCDataFieldSet().add("logic");
-        modelWriter.getCDataFieldSet().add("uiLogic");
-
-        final var baOutputStream = new ByteArrayOutputStream();
-        modelWriter.write(model, baOutputStream);
-        final var baInputStream = new ByteArrayInputStream(baOutputStream.toByteArray());
-        final var byteArrayModel = modelReader.read(baInputStream);
-
-        checkModelEquality(model, byteArrayModel, "test model does not equal XML marshalled and unmarshalled model");
-
-        LOGGER.debug("ran testApexModelWriteReadXML");
-    }
-
-    /**
      * Test write and read in JSON format.
      *
      * @throws ApexException on write/read errors
@@ -138,7 +89,7 @@ public class TestApexModel<M extends AxModel> {
         // Write the file to disk
         File jsonFile;
         try {
-            jsonFile = File.createTempFile("ApexModel", ".xml");
+            jsonFile = File.createTempFile("ApexModel", ".json");
             jsonFile.deleteOnExit();
         } catch (final Exception e) {
             LOGGER.warn(TEMP_FILE_CREATE_ERR_STR, e);
@@ -159,7 +110,6 @@ public class TestApexModel<M extends AxModel> {
         }
 
         final ApexModelWriter<M> modelWriter = new ApexModelWriter<>(rootModelClass);
-        modelWriter.setJsonOutput(true);
 
         final var baOutputStream = new ByteArrayOutputStream();
         modelWriter.write(model, baOutputStream);
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/xml/AxReferenceKeyAdapter.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/xml/AxReferenceKeyAdapter.java
deleted file mode 100644
index 8515f5724..000000000
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/xml/AxReferenceKeyAdapter.java
+++ /dev/null
@@ -1,58 +0,0 @@
-/*-
- * ============LICENSE_START=======================================================
- *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- *  Modifications Copyright (C) 2021 Nordix Foundation.
- * ================================================================================
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- * SPDX-License-Identifier: Apache-2.0
- * ============LICENSE_END=========================================================
- */
-
-package org.onap.policy.apex.model.basicmodel.xml;
-
-import java.io.Serializable;
-import javax.xml.bind.annotation.XmlAccessType;
-import javax.xml.bind.annotation.XmlAccessorType;
-import javax.xml.bind.annotation.XmlType;
-import javax.xml.bind.annotation.adapters.XmlAdapter;
-import org.onap.policy.apex.model.basicmodel.concepts.AxReferenceKey;
-
-/**
- * This class manages marshaling and unmarshaling of Apex {@link AxReferenceKey} concepts using JAXB. The local name in
- * reference keys must have specific handling.
- */
-@XmlAccessorType(XmlAccessType.PROPERTY)
-@XmlType(namespace = "http://www.onap.org/policy/apex-pdp")
-public class AxReferenceKeyAdapter extends XmlAdapter<String, AxReferenceKey> implements Serializable {
-
-    private static final long serialVersionUID = -3480405083900107029L;
-
-    /**
-     * {@inheritDoc}.
-     */
-    @Override
-    public final String marshal(final AxReferenceKey key) throws Exception {
-        return key.getLocalName();
-    }
-
-    /**
-     * {@inheritDoc}.
-     */
-    @Override
-    public final AxReferenceKey unmarshal(final String key) throws Exception {
-        final var axReferenceKey = new AxReferenceKey();
-        axReferenceKey.setLocalName(key);
-        return axReferenceKey;
-    }
-}
diff --git a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/xml/package-info.java b/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/xml/package-info.java
deleted file mode 100644
index 290209d89..000000000
--- a/model/basic-model/src/main/java/org/onap/policy/apex/model/basicmodel/xml/package-info.java
+++ /dev/null
@@ -1,34 +0,0 @@
-/*-
- * ============LICENSE_START=======================================================
- *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- * ================================================================================
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- * SPDX-License-Identifier: Apache-2.0
- * ============LICENSE_END=========================================================
- */
-
-/**
- * Contains utility classes for managing marshaling and unmarshaling of APEX models using JAXB.
- *
- * @author Liam Fallon (liam.fallon@ericsson.com)
- */
-
-@XmlSchema(namespace = "http://www.onap.org/policy/apex-pdp", elementFormDefault = XmlNsForm.QUALIFIED,
-        xmlns = { @XmlNs(namespaceURI = "http://www.onap.org/policy/apex-pdp", prefix = "") })
-
-package org.onap.policy.apex.model.basicmodel.xml;
-
-import javax.xml.bind.annotation.XmlNs;
-import javax.xml.bind.annotation.XmlNsForm;
-import javax.xml.bind.annotation.XmlSchema;
diff --git a/model/basic-model/src/main/resources/xml/example.xsd b/model/basic-model/src/main/resources/xml/example.xsd
deleted file mode 100644
index 75ecdc323..000000000
--- a/model/basic-model/src/main/resources/xml/example.xsd
+++ /dev/null
@@ -1,100 +0,0 @@
-<?xml version="1.0" standalone="yes"?>
-<!--
-  ============LICENSE_START=======================================================
-   Copyright (C) 2016-2018 Ericsson. All rights reserved.
-  ================================================================================
-  Licensed under the Apache License, Version 2.0 (the "License");
-  you may not use this file except in compliance with the License.
-  You may obtain a copy of the License at
-  
-       http://www.apache.org/licenses/LICENSE-2.0
-  
-  Unless required by applicable law or agreed to in writing, software
-  distributed under the License is distributed on an "AS IS" BASIS,
-  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-  See the License for the specific language governing permissions and
-  limitations under the License.
-  
-  SPDX-License-Identifier: Apache-2.0
-  ============LICENSE_END=========================================================
--->
-<xs:schema elementFormDefault="qualified" version="1.0" targetNamespace="http://www.onap.org/policy/apex-pdp" xmlns="http://www.onap.org/policy/apex-pdp" xmlns:tns="http://www.onap.org/policy/apex-pdp" xmlns:xs="http://www.w3.org/2001/XMLSchema">
-
-  <xs:element name="apexArtifactKey" type="AxArtifactKey"/>
-
-  <xs:element name="apexKeyInfo" type="AxKeyInfo"/>
-
-  <xs:element name="apexModel" type="AxModel"/>
-
-  <xs:complexType name="AxModel">
-    <xs:complexContent>
-      <xs:extension base="AxConcept">
-        <xs:sequence>
-          <xs:element name="key" form="unqualified" type="AxArtifactKey"/>
-          <xs:element name="keyInformation" type="AxKeyInformation"/>
-        </xs:sequence>
-      </xs:extension>
-    </xs:complexContent>
-  </xs:complexType>
-
-  <xs:complexType name="AxConcept" abstract="true">
-    <xs:sequence/>
-  </xs:complexType>
-
-  <xs:complexType name="AxArtifactKey">
-    <xs:complexContent>
-      <xs:extension base="axKey">
-        <xs:sequence>
-          <xs:element name="name" type="xs:string"/>
-          <xs:element name="version" type="xs:string"/>
-        </xs:sequence>
-      </xs:extension>
-    </xs:complexContent>
-  </xs:complexType>
-
-  <xs:complexType name="axKey" abstract="true">
-    <xs:complexContent>
-      <xs:extension base="AxConcept">
-        <xs:sequence/>
-      </xs:extension>
-    </xs:complexContent>
-  </xs:complexType>
-
-  <xs:complexType name="AxKeyInformation">
-    <xs:complexContent>
-      <xs:extension base="AxConcept">
-        <xs:sequence>
-          <xs:element name="key" form="unqualified" type="AxArtifactKey"/>
-          <xs:element name="keyInfoMap">
-            <xs:complexType>
-              <xs:sequence>
-                <xs:element name="entry" minOccurs="0" maxOccurs="unbounded" form="unqualified">
-                  <xs:complexType>
-                    <xs:sequence>
-                      <xs:element name="key" form="unqualified" minOccurs="0" type="AxArtifactKey"/>
-                      <xs:element name="value" form="unqualified" minOccurs="0" type="AxKeyInfo"/>
-                    </xs:sequence>
-                  </xs:complexType>
-                </xs:element>
-              </xs:sequence>
-            </xs:complexType>
-          </xs:element>
-        </xs:sequence>
-      </xs:extension>
-    </xs:complexContent>
-  </xs:complexType>
-
-  <xs:complexType name="AxKeyInfo">
-    <xs:complexContent>
-      <xs:extension base="AxConcept">
-        <xs:sequence>
-          <xs:element name="key" form="unqualified" type="AxArtifactKey"/>
-          <xs:element name="UUID" type="xs:string"/>
-          <xs:element name="description" type="xs:string"/>
-        </xs:sequence>
-      </xs:extension>
-    </xs:complexContent>
-  </xs:complexType>
-</xs:schema>
-
-
diff --git a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/concepts/DummyEntity.java b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/concepts/DummyEntity.java
index cd8b52ce6..2b16e89ed 100644
--- a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/concepts/DummyEntity.java
+++ b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/concepts/DummyEntity.java
@@ -23,17 +23,11 @@ package org.onap.policy.apex.model.basicmodel.concepts;
 
 import java.util.Arrays;
 import java.util.List;
-import javax.xml.bind.annotation.XmlElement;
-import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;
-import org.onap.policy.apex.model.basicmodel.xml.AxReferenceKeyAdapter;
 
 public class DummyEntity extends AxConcept {
     private static final long serialVersionUID = -2962570563281067894L;
 
-    @XmlElement(name = "key", required = true)
-    @XmlJavaTypeAdapter(AxReferenceKeyAdapter.class)
     protected AxReferenceKey key;
-
     private double doubleValue;
 
     public DummyEntity() {
diff --git a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelFileWriterTest.java b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelFileWriterTest.java
index 331e57f47..0f8f956ab 100644
--- a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelFileWriterTest.java
+++ b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelFileWriterTest.java
@@ -1,7 +1,7 @@
 /*
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- *  Modifications Copyright (C) 2020 Nordix Foundation
+ *  Modifications Copyright (C) 2020,2022 Nordix Foundation
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -36,33 +36,27 @@ public class ApexModelFileWriterTest {
     public void testModelFileWriter() throws IOException, ApexException {
         ApexModelFileWriter<AxModel> modelFileWriter = new ApexModelFileWriter<>(true);
 
-        modelFileWriter.setValidateFlag(true);
-        assertTrue(modelFileWriter.isValidateFlag());
+        modelFileWriter.setValidate(true);
+        assertTrue(modelFileWriter.isValidate());
 
         File tempFile = File.createTempFile("ApexFileWriterTest", "test");
         File tempDir = tempFile.getParentFile();
 
         File jsonTempFile = new File(tempDir.getAbsolutePath() + "/aaa/ApexFileWriterTest.json");
-        File xmlTempFile = new File(tempDir.getAbsolutePath() + "/ccc/ApexFileWriterTest.xml");
 
         AxModel model = new DummyApexBasicModelCreator().getModel();
 
         modelFileWriter.apexModelWriteJsonFile(model, AxModel.class, jsonTempFile.getAbsolutePath());
-        modelFileWriter.apexModelWriteXmlFile(model, AxModel.class, xmlTempFile.getAbsolutePath());
 
         jsonTempFile.delete();
-        xmlTempFile.delete();
         new File(tempDir.getAbsolutePath() + "/aaa").delete();
         new File(tempDir.getAbsolutePath() + "/ccc").delete();
 
         jsonTempFile = new File(tempDir.getAbsolutePath() + "/aaa/bbb/ApexFileWriterTest.json");
-        xmlTempFile = new File(tempDir.getAbsolutePath() + "/ccc/ddd/ApexFileWriterTest.xml");
 
         modelFileWriter.apexModelWriteJsonFile(model, AxModel.class, jsonTempFile.getAbsolutePath());
-        modelFileWriter.apexModelWriteXmlFile(model, AxModel.class, xmlTempFile.getAbsolutePath());
 
         jsonTempFile.delete();
-        xmlTempFile.delete();
 
         new File(tempDir.getAbsolutePath() + "/aaa/bbb").delete();
         new File(tempDir.getAbsolutePath() + "/aaa").delete();
@@ -70,19 +64,14 @@ public class ApexModelFileWriterTest {
         new File(tempDir.getAbsolutePath() + "/ccc").delete();
 
         File dirA = new File(tempDir.getAbsolutePath() + "/aaa");
-        //File dirB = new File(tempDir.getAbsolutePath() + "/aaa/bbb");
+        // File dirB = new File(tempDir.getAbsolutePath() + "/aaa/bbb");
         dirA.createNewFile();
-        //dirB.createNewFile();
+        // dirB.createNewFile();
 
         jsonTempFile = new File(tempDir.getAbsolutePath() + "/aaa/bbb/ApexFileWriterTest.json");
-        jsonTempFile = new File(tempDir.getAbsolutePath() + "/aaa/bbb/ApexFileWriterTest.xml");
         final File jsonTempFile01 = jsonTempFile;
-        assertThatThrownBy(() -> modelFileWriter.apexModelWriteJsonFile(model, AxModel.class,
-                jsonTempFile01.getAbsolutePath()))
-                .hasMessageContaining("could not create directory");
-
-        assertThatThrownBy(() -> modelFileWriter.apexModelWriteXmlFile(model, AxModel.class,
-                jsonTempFile01.getAbsolutePath()))
+        assertThatThrownBy(
+            () -> modelFileWriter.apexModelWriteJsonFile(model, AxModel.class, jsonTempFile01.getAbsolutePath()))
                 .hasMessageContaining("could not create directory");
 
         dirA.delete();
@@ -93,15 +82,10 @@ public class ApexModelFileWriterTest {
         fileB.createNewFile();
 
         jsonTempFile = new File(tempDir.getAbsolutePath() + "/aaa/bbb/ApexFileWriterTest.json");
-        jsonTempFile = new File(tempDir.getAbsolutePath() + "/aaa/bbb/ApexFileWriterTest.xml");
 
         File jsonTempFile02 = jsonTempFile;
-        assertThatThrownBy(() -> modelFileWriter.apexModelWriteJsonFile(model, AxModel.class,
-                jsonTempFile02.getAbsolutePath()))
-                .hasMessageContaining("error processing file");
-
-        assertThatThrownBy(() -> modelFileWriter.apexModelWriteXmlFile(model, AxModel.class,
-                jsonTempFile02.getAbsolutePath()))
+        assertThatThrownBy(
+            () -> modelFileWriter.apexModelWriteJsonFile(model, AxModel.class, jsonTempFile02.getAbsolutePath()))
                 .hasMessageContaining("error processing file");
 
         fileB.delete();
diff --git a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelReaderTest.java b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelReaderTest.java
index d75f20253..1152771ea 100644
--- a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelReaderTest.java
+++ b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelReaderTest.java
@@ -1,7 +1,7 @@
 /*
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- *  Modifications Copyright (C) 2020 Nordix Foundation
+ *  Modifications Copyright (C) 2020,2022 Nordix Foundation
  *  Modifications Copyright (C) 2021 AT&T Intellectual Property. All rights reserved.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -34,45 +34,33 @@ import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileReader;
 import java.io.IOException;
-import java.lang.reflect.Field;
-import javax.xml.bind.JAXBException;
-import javax.xml.bind.PropertyException;
-import javax.xml.bind.Unmarshaller;
-import javax.xml.transform.stream.StreamSource;
 import org.junit.Test;
 import org.junit.runner.RunWith;
-import org.mockito.Mock;
-import org.mockito.Mockito;
-import org.mockito.MockitoAnnotations;
 import org.mockito.runners.MockitoJUnitRunner;
 import org.onap.policy.apex.model.basicmodel.concepts.ApexException;
 import org.onap.policy.apex.model.basicmodel.concepts.AxModel;
 
 @RunWith(MockitoJUnitRunner.class)
 public class ApexModelReaderTest {
-    @Mock
-    private Unmarshaller unmarshallerMock;
-
     @Test
     public void testModelReader() throws IOException, ApexException {
         AxModel model = new DummyApexBasicModelCreator().getModel();
         AxModel invalidModel = new DummyApexBasicModelCreator().getInvalidModel();
 
         ApexModelWriter<AxModel> modelWriter = new ApexModelWriter<AxModel>(AxModel.class);
-        modelWriter.setValidateFlag(true);
-        modelWriter.setJsonOutput(true);
+        modelWriter.setValidate(true);
 
         ByteArrayOutputStream baos = new ByteArrayOutputStream();
         modelWriter.write(model, baos);
 
         ByteArrayOutputStream baosInvalid = new ByteArrayOutputStream();
-        modelWriter.setValidateFlag(false);
+        modelWriter.setValidate(false);
         modelWriter.write(invalidModel, baosInvalid);
 
         ApexModelReader<AxModel> modelReader = new ApexModelReader<AxModel>(AxModel.class, true);
 
-        modelReader.setValidateFlag(true);
-        assertTrue(modelReader.getValidateFlag());
+        modelReader.setValidate(true);
+        assertTrue(modelReader.isValidate());
 
         ByteArrayInputStream bais = new ByteArrayInputStream(baos.toByteArray());
         AxModel readModel = modelReader.read(bais);
@@ -81,26 +69,24 @@ public class ApexModelReaderTest {
         ByteArrayInputStream baisInvalid = new ByteArrayInputStream(baosInvalid.toByteArray());
         assertThatThrownBy(() -> modelReader.read(baisInvalid))
             .hasMessageStartingWith("Apex concept validation failed");
-        modelReader.setValidateFlag(false);
-        assertFalse(modelReader.getValidateFlag());
+        modelReader.setValidate(false);
+        assertFalse(modelReader.isValidate());
 
         ByteArrayInputStream bais2 = new ByteArrayInputStream(baos.toByteArray());
         AxModel readModel2 = modelReader.read(bais2);
         assertEquals(model, readModel2);
 
-        modelWriter.setJsonOutput(false);
-
-        ByteArrayOutputStream baosXml = new ByteArrayOutputStream();
-        modelWriter.write(model, baosXml);
+        ByteArrayOutputStream baosJson = new ByteArrayOutputStream();
+        modelWriter.write(model, baosJson);
 
-        ByteArrayInputStream baisXml = new ByteArrayInputStream(baosXml.toByteArray());
-        AxModel readModelXml = modelReader.read(baisXml);
-        assertEquals(model, readModelXml);
+        ByteArrayInputStream baisJson = new ByteArrayInputStream(baosJson.toByteArray());
+        AxModel readModelJson = modelReader.read(baisJson);
+        assertEquals(model, readModelJson);
 
         String dummyString = "SomeDummyText";
         ByteArrayInputStream baisDummy = new ByteArrayInputStream(dummyString.getBytes());
         assertThatThrownBy(() -> modelReader.read(baisDummy))
-            .hasMessage("format of input for Apex concept is neither JSON nor XML");
+            .hasMessageContaining("Unable to unmarshal Apex concept");
         ByteArrayInputStream nullBais = null;
         assertThatThrownBy(() -> modelReader.read(nullBais))
             .hasMessage("concept stream may not be null");
@@ -115,42 +101,5 @@ public class ApexModelReaderTest {
         assertThatThrownBy(() -> modelReader.read(br))
              .hasMessage("Unable to read Apex concept ");
         tempFile.delete();
-        modelReader.setSchema(null);
-
-        final File tempFileA = File.createTempFile("Apex", "Dummy");
-        assertThatThrownBy(() -> modelReader.setSchema(tempFileA.getCanonicalPath()))
-            .hasMessage("Unable to load schema");
-        tempFile.delete();
-        modelReader.setSchema("xml/example.xsd");
-    }
-
-    @Test
-    public void testSetInputTypeError() throws ApexModelException,
-        NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException {
-        MockitoAnnotations.initMocks(this);
-
-        ApexModelReader<AxModel> modelReader = new ApexModelReader<AxModel>(AxModel.class, true);
-
-        Field marshallerField = modelReader.getClass().getDeclaredField("unmarshaller");
-        marshallerField.setAccessible(true);
-        marshallerField.set(modelReader, unmarshallerMock);
-        marshallerField.setAccessible(false);
-
-        assertThatThrownBy(() -> {
-            Mockito.doThrow(new JAXBException("Exception marshalling to JSON")).when(unmarshallerMock)
-                .unmarshal((StreamSource) Mockito.anyObject(), Mockito.anyObject());
-
-            modelReader.read("{Hello}");
-        }).hasMessage("Unable to unmarshal Apex concept ");
-        assertThatThrownBy(() -> {
-            Mockito.doThrow(new PropertyException("Exception setting JAXB property")).when(unmarshallerMock)
-                .setProperty(Mockito.anyString(), Mockito.anyString());
-            modelReader.read("{Hello}");
-        }).hasMessage("JAXB error setting unmarshaller for JSON input");
-        assertThatThrownBy(() -> {
-            Mockito.doThrow(new PropertyException("Exception setting JAXB property")).when(unmarshallerMock)
-                .setProperty(Mockito.anyString(), Mockito.anyString());
-            modelReader.read("<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
-        }).hasMessage("JAXB error setting unmarshaller for XML input");
     }
 }
diff --git a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelSaverTest.java b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelSaverTest.java
index ad897832e..c95106aa8 100644
--- a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelSaverTest.java
+++ b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelSaverTest.java
@@ -1,7 +1,7 @@
 /*
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- *  Modifications Copyright (C) 2020 Nordix Foundation
+ *  Modifications Copyright (C) 2020,2022 Nordix Foundation
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -41,14 +41,12 @@ public class ApexModelSaverTest {
         Path tempPath = Files.createTempDirectory("ApexTest");
         assertNotNull(tempPath);
 
-        ApexModelSaver<AxModel> modelSaver = new ApexModelSaver<AxModel>(AxModel.class, model,
-                        tempPath.toAbsolutePath().toString());
+        ApexModelSaver<AxModel> modelSaver =
+            new ApexModelSaver<AxModel>(AxModel.class, model, tempPath.toAbsolutePath().toString());
         assertNotNull(modelSaver);
-        modelSaver.apexModelWriteXml();
         modelSaver.apexModelWriteJson();
 
         Files.deleteIfExists(new File(tempPath.toAbsolutePath() + "/BasicModel.json").toPath());
-        Files.deleteIfExists(new File(tempPath.toAbsolutePath() + "/BasicModel.xml").toPath());
         Files.deleteIfExists(tempPath);
     }
 }
diff --git a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelStringWriterTest.java b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelStringWriterTest.java
index 0b8d789ad..13e72d3e2 100644
--- a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelStringWriterTest.java
+++ b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelStringWriterTest.java
@@ -1,7 +1,7 @@
 /*
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- *  Modifications Copyright (C) 2020 Nordix Foundation
+ *  Modifications Copyright (C) 2020,2022 Nordix Foundation
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -38,33 +38,26 @@ public class ApexModelStringWriterTest {
         AxModel basicModel = new DummyApexBasicModelCreator().getModel();
         assertNotNull(basicModel);
 
-        AxKeyInfo intKeyInfo   = basicModel.getKeyInformation().get("IntegerKIKey");
+        AxKeyInfo intKeyInfo = basicModel.getKeyInformation().get("IntegerKIKey");
         AxKeyInfo floatKeyInfo = basicModel.getKeyInformation().get("FloatKIKey");
 
         // Ensure marshalling is OK
         ApexModelStringWriter<AxKeyInfo> stringWriter = new ApexModelStringWriter<AxKeyInfo>(true);
 
-        assertNotNull(stringWriter.writeJsonString(intKeyInfo,   AxKeyInfo.class));
+        assertNotNull(stringWriter.writeJsonString(intKeyInfo, AxKeyInfo.class));
         assertNotNull(stringWriter.writeJsonString(floatKeyInfo, AxKeyInfo.class));
 
-        assertNotNull(stringWriter.writeString(intKeyInfo,   AxKeyInfo.class, true));
-        assertNotNull(stringWriter.writeString(floatKeyInfo, AxKeyInfo.class, true));
+        assertNotNull(stringWriter.writeString(intKeyInfo, AxKeyInfo.class));
+        assertNotNull(stringWriter.writeString(floatKeyInfo, AxKeyInfo.class));
 
-        assertNotNull(stringWriter.writeString(intKeyInfo,   AxKeyInfo.class, false));
-        assertNotNull(stringWriter.writeString(floatKeyInfo, AxKeyInfo.class, false));
+        assertNotNull(stringWriter.writeString(intKeyInfo, AxKeyInfo.class));
+        assertNotNull(stringWriter.writeString(floatKeyInfo, AxKeyInfo.class));
 
-        assertNotNull(stringWriter.writeXmlString(intKeyInfo,   AxKeyInfo.class));
-        assertNotNull(stringWriter.writeXmlString(floatKeyInfo, AxKeyInfo.class));
-
-        assertThatThrownBy(() -> stringWriter.writeString(null, AxKeyInfo.class, true))
-            .hasMessage("concept may not be null");
-        assertThatThrownBy(() -> stringWriter.writeString(null, AxKeyInfo.class, false))
-            .hasMessage("concept may not be null");
+        assertThatThrownBy(() -> stringWriter.writeString(null, AxKeyInfo.class)).hasMessage("concept may not be null");
+        assertThatThrownBy(() -> stringWriter.writeString(null, AxKeyInfo.class)).hasMessage("concept may not be null");
         assertThatThrownBy(() -> stringWriter.writeJsonString(null, AxKeyInfo.class))
             .hasMessage("error writing JSON string");
-        assertThatThrownBy(() -> stringWriter.writeXmlString(null, AxKeyInfo.class))
-            .hasMessage("error writing XML string");
-        stringWriter.setValidateFlag(true);
-        assertTrue(stringWriter.isValidateFlag());
+        stringWriter.setValidate(true);
+        assertTrue(stringWriter.isValidate());
     }
 }
diff --git a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelWriterTest.java b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelWriterTest.java
index 147eb206a..063855976 100644
--- a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelWriterTest.java
+++ b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexModelWriterTest.java
@@ -1,7 +1,7 @@
 /*
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- *  Modifications Copyright (C) 2020 Nordix Foundation
+ *  Modifications Copyright (C) 2020,2022 Nordix Foundation
  *  Modifications Copyright (C) 2021 AT&T Intellectual Property. All rights reserved.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -23,65 +23,38 @@
 package org.onap.policy.apex.model.basicmodel.handling;
 
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
-import java.io.Writer;
-import java.lang.reflect.Field;
-import javax.xml.bind.JAXBException;
-import javax.xml.bind.Marshaller;
-import javax.xml.bind.PropertyException;
 import org.junit.Test;
 import org.junit.runner.RunWith;
-import org.mockito.Mock;
-import org.mockito.Mockito;
-import org.mockito.MockitoAnnotations;
 import org.mockito.runners.MockitoJUnitRunner;
 import org.onap.policy.apex.model.basicmodel.concepts.ApexException;
 import org.onap.policy.apex.model.basicmodel.concepts.AxModel;
-import org.w3c.dom.Document;
 
 @RunWith(MockitoJUnitRunner.class)
 public class ApexModelWriterTest {
-    @Mock
-    private Marshaller marshallerMock;
-
     @Test
     public void testModelWriter() throws IOException, ApexException {
         ApexModelWriter<AxModel> modelWriter = new ApexModelWriter<AxModel>(AxModel.class);
 
-        modelWriter.setValidateFlag(true);
-        assertTrue(modelWriter.getValidateFlag());
-        assertEquals(0, modelWriter.getCDataFieldSet().size());
-
-        assertFalse(modelWriter.isJsonOutput());
-        modelWriter.setJsonOutput(true);
-        assertTrue(modelWriter.isJsonOutput());
-        modelWriter.setJsonOutput(false);
-        assertFalse(modelWriter.isJsonOutput());
+        modelWriter.setValidate(true);
+        assertTrue(modelWriter.isValidate());
 
         ByteArrayOutputStream baos = new ByteArrayOutputStream();
 
         AxModel model = new DummyApexBasicModelCreator().getModel();
 
         modelWriter.write(model, baos);
-        modelWriter.setJsonOutput(true);
-        modelWriter.write(model, baos);
-        modelWriter.setJsonOutput(false);
 
-        modelWriter.setValidateFlag(false);
+        modelWriter.setValidate(false);
         modelWriter.write(model, baos);
-        modelWriter.setJsonOutput(true);
-        modelWriter.write(model, baos);
-        modelWriter.setJsonOutput(false);
 
-        modelWriter.setValidateFlag(true);
+        modelWriter.setValidate(true);
         model.getKeyInformation().getKeyInfoMap().clear();
         assertThatThrownBy(() -> modelWriter.write(model, baos))
-            .hasMessageContaining("Apex concept xml (BasicModel:0.0.1) validation failed");
+            .hasMessageContaining("Apex concept (BasicModel:0.0.1) validation failed");
         model.getKeyInformation().generateKeyInfo(model);
 
         assertThatThrownBy(() -> modelWriter.write(null, baos))
@@ -91,73 +64,4 @@ public class ApexModelWriterTest {
         assertThatThrownBy(() -> modelWriter.write(model, nullBaos))
             .hasMessage("concept stream may not be null");
     }
-
-    @Test
-    public void testSetOutputTypeError() throws ApexModelException, NoSuchFieldException, SecurityException,
-            IllegalArgumentException, IllegalAccessException, PropertyException {
-        MockitoAnnotations.initMocks(this);
-
-        ApexModelWriter<AxModel> modelWriter = new ApexModelWriter<AxModel>(AxModel.class);
-
-        Field marshallerField = modelWriter.getClass().getDeclaredField("marshaller");
-        marshallerField.setAccessible(true);
-        marshallerField.set(modelWriter, marshallerMock);
-        marshallerField.setAccessible(false);
-        Mockito.doThrow(new PropertyException("Exception setting JAXB property")).when(marshallerMock)
-            .setProperty(Mockito.anyString(), Mockito.anyString());
-        assertThatThrownBy(() -> modelWriter.setJsonOutput(true))
-            .hasMessage("JAXB error setting marshaller for JSON output");
-        Mockito.doThrow(new PropertyException("Exception setting JAXB property")).when(marshallerMock)
-            .setProperty(Mockito.anyString(), Mockito.anyString());
-        assertThatThrownBy(() -> modelWriter.setJsonOutput(false))
-            .hasMessage("JAXB error setting marshaller for XML output");
-    }
-
-    @Test
-    public void testOutputJsonError() throws ApexModelException, NoSuchFieldException, SecurityException,
-            IllegalArgumentException, IllegalAccessException, JAXBException {
-        MockitoAnnotations.initMocks(this);
-
-        ApexModelWriter<AxModel> modelWriter = new ApexModelWriter<AxModel>(AxModel.class);
-
-        Field marshallerField = modelWriter.getClass().getDeclaredField("marshaller");
-        marshallerField.setAccessible(true);
-        marshallerField.set(modelWriter, marshallerMock);
-        marshallerField.setAccessible(false);
-
-        modelWriter.setValidateFlag(false);
-        modelWriter.setJsonOutput(true);
-
-        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        AxModel model = new DummyApexBasicModelCreator().getModel();
-        Mockito.doThrow(new JAXBException("Exception marshalling to JSON")).when(marshallerMock)
-            .marshal((AxModel) Mockito.anyObject(), (Writer) Mockito.anyObject());
-        assertThatThrownBy(() -> modelWriter.write(model, baos)).hasMessage("Unable to marshal Apex concept to JSON");
-    }
-
-    @Test
-    public void testOutputXmlError() throws ApexModelException, NoSuchFieldException, SecurityException,
-            IllegalArgumentException, IllegalAccessException, JAXBException {
-        MockitoAnnotations.initMocks(this);
-
-        ApexModelWriter<AxModel> modelWriter = new ApexModelWriter<AxModel>(AxModel.class);
-        modelWriter.setJsonOutput(false);
-
-        Field marshallerField = modelWriter.getClass().getDeclaredField("marshaller");
-        marshallerField.setAccessible(true);
-        marshallerField.set(modelWriter, marshallerMock);
-        marshallerField.setAccessible(false);
-
-        modelWriter.setValidateFlag(false);
-        modelWriter.setJsonOutput(false);
-
-        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        AxModel model = new DummyApexBasicModelCreator().getModel();
-
-        Mockito.doThrow(new JAXBException("Exception marshalling to JSON")).when(marshallerMock)
-            .marshal((AxModel) Mockito.anyObject(), (Document) Mockito.anyObject());
-
-        assertThatThrownBy(() -> modelWriter.write(model, baos))
-            .hasMessage("Unable to marshal Apex concept to XML");
-    }
 }
diff --git a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexSchemaGeneratorTest.java b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexSchemaGeneratorTest.java
deleted file mode 100644
index 3385830e2..000000000
--- a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/ApexSchemaGeneratorTest.java
+++ /dev/null
@@ -1,95 +0,0 @@
-/*-
- * ============LICENSE_START=======================================================
- *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- * ================================================================================
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- * SPDX-License-Identifier: Apache-2.0
- * ============LICENSE_END=========================================================
- */
-
-package org.onap.policy.apex.model.basicmodel.handling;
-
-import static org.junit.Assert.assertTrue;
-
-import java.io.ByteArrayOutputStream;
-import java.io.File;
-import java.io.FileDescriptor;
-import java.io.FileOutputStream;
-import java.io.IOException;
-import java.io.PrintStream;
-import org.junit.After;
-import org.junit.Test;
-
-public class ApexSchemaGeneratorTest {
-    private final PrintStream stdout = System.out;
-
-    @After
-    public void tearDown() throws Exception {
-        System.setOut(stdout);
-    }
-
-    @Test
-    public void test() throws IOException {
-        final ByteArrayOutputStream baos0 = new ByteArrayOutputStream();
-        System.setOut(new PrintStream(baos0));
-
-        final String[] args0 = {};
-        ApexSchemaGenerator.main(args0);
-        assertTrue(baos0.toString().contains("usage: ApexSchemaGenerator apex-root-class [schema-file-name]"));
-        System.setOut(new PrintStream(new FileOutputStream(FileDescriptor.out)));
-
-        final ByteArrayOutputStream baos1 = new ByteArrayOutputStream();
-        System.setOut(new PrintStream(baos1));
-
-        final String[] args1 = { "hello", "goodbye", "here" };
-        ApexSchemaGenerator.main(args1);
-        assertTrue(baos1.toString().contains("usage: ApexSchemaGenerator apex-root-class [schema-file-name]"));
-        System.setOut(new PrintStream(new FileOutputStream(FileDescriptor.out)));
-
-        final ByteArrayOutputStream baos2 = new ByteArrayOutputStream();
-        System.setOut(new PrintStream(baos2));
-
-        final String[] args2 = { "hello", "goodbye" };
-        ApexSchemaGenerator.main(args2);
-        assertTrue(baos2.toString().contains("error on Apex schema output"));
-        System.setOut(new PrintStream(new FileOutputStream(FileDescriptor.out)));
-
-        final ByteArrayOutputStream baos3 = new ByteArrayOutputStream();
-        System.setOut(new PrintStream(baos3));
-
-        final String[] args3 = { "hello" };
-        ApexSchemaGenerator.main(args3);
-        assertTrue(baos3.toString().contains("could not create JAXB context, root class hello not found"));
-        System.setOut(new PrintStream(new FileOutputStream(FileDescriptor.out)));
-
-        final ByteArrayOutputStream baos4 = new ByteArrayOutputStream();
-        System.setOut(new PrintStream(baos4));
-
-        final String[] args4 = { "org.onap.policy.apex.model.basicmodel.concepts.AxModel" };
-        ApexSchemaGenerator.main(args4);
-        assertTrue(baos4.toString().contains("targetNamespace=\"http://www.onap.org/policy/apex-pdp\""));
-        System.setOut(new PrintStream(new FileOutputStream(FileDescriptor.out)));
-
-        final ByteArrayOutputStream baos5 = new ByteArrayOutputStream();
-        System.setOut(new PrintStream(baos5));
-
-        final File tempFile = File.createTempFile("ApexSchemaGeneratorTest", "xsd");
-        tempFile.deleteOnExit();
-        final String[] args5 =
-            { "org.onap.policy.apex.model.basicmodel.concepts.AxModel", tempFile.getCanonicalPath() };
-
-        ApexSchemaGenerator.main(args5);
-        assertTrue(tempFile.length() > 100);
-    }
-}
diff --git a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/SupportApexBasicModelTest.java b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/SupportApexBasicModelTest.java
index bb9776fc7..68f755886 100644
--- a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/SupportApexBasicModelTest.java
+++ b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/SupportApexBasicModelTest.java
@@ -110,11 +110,6 @@ public class SupportApexBasicModelTest {
     }
 
     @Test
-    public void testModelWriteReadXml() throws Exception {
-        testApexModel.testApexModelWriteReadXml();
-    }
-
-    @Test
     public void testModelWriteReadJson() throws Exception {
         testApexModel.testApexModelWriteReadJson();
     }
diff --git a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/SupportBasicModelTest.java b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/SupportBasicModelTest.java
index 5fc678ac0..d55a9da29 100644
--- a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/SupportBasicModelTest.java
+++ b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/SupportBasicModelTest.java
@@ -1,7 +1,7 @@
 /*-
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- *  Modifications Copyright (C) 2020-2021 Nordix Foundation
+ *  Modifications Copyright (C) 2020-2022 Nordix Foundation
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -43,7 +43,6 @@ public class SupportBasicModelTest {
         testApexModel.testApexModelVaidateMalstructured();
 
         testApexModel.testApexModelWriteReadJson();
-        testApexModel.testApexModelWriteReadXml();
     }
 
     @Test
@@ -102,14 +101,11 @@ public class SupportBasicModelTest {
     }
 
     @Test
-    public void testModelCreator1XmlJson() throws ApexException {
+    public void testModelCreator1Json() throws ApexException {
         final TestApexModel<AxModel> testApexModel = new TestApexModel<AxModel>(AxModel.class,
             new SupportApexModelCreator1());
 
         assertThatThrownBy(() -> testApexModel.testApexModelWriteReadJson())
             .hasMessageStartingWith("error processing file");
-
-        assertThatThrownBy(() -> testApexModel.testApexModelWriteReadXml())
-            .hasMessageStartingWith("error processing file");
     }
 }
diff --git a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/SupportConceptGetterTest.java b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/SupportConceptGetterTest.java
index 006c583ec..1783fc00f 100644
--- a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/SupportConceptGetterTest.java
+++ b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/handling/SupportConceptGetterTest.java
@@ -1,7 +1,7 @@
 /*
  * ============LICENSE_START=======================================================
  *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- *  Modifications Copyright (C) 2020-2021 Nordix Foundation.
+ *  Modifications Copyright (C) 2020-2022 Nordix Foundation.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -156,19 +156,19 @@ public class SupportConceptGetterTest {
         ApexModelReader<AxModel> modelReader = new ApexModelReader<AxModel>(AxModel.class);
         ApexModelFileWriter<AxModel> modelWriter = new ApexModelFileWriter<AxModel>(true);
 
-        modelReader.setValidateFlag(false);
-        modelWriter.setValidateFlag(false);
+        modelReader.setValidate(false);
+        modelWriter.setValidate(false);
 
-        File tempXmlFile = File.createTempFile("ApexModel", "xml");
-        modelWriter.apexModelWriteJsonFile(basicModel, AxModel.class, tempXmlFile.getCanonicalPath());
+        File tempJsonFile = File.createTempFile("ApexModel", "json");
+        modelWriter.apexModelWriteJsonFile(basicModel, AxModel.class, tempJsonFile.getCanonicalPath());
 
-        FileInputStream xmlFileInputStream = new FileInputStream(tempXmlFile);
-        AxModel readXmlModel = modelReader.read(xmlFileInputStream);
-        xmlFileInputStream.close();
-        assertEquals(basicModel, readXmlModel);
-        assertEquals(intKI91, readXmlModel.getKeyInformation().get("IntegerKIKey91"));
-        assertNotNull(readXmlModel.getKeyInformation().get("FloatKIKey"));
-        tempXmlFile.delete();
+        FileInputStream jsonFileInputStream = new FileInputStream(tempJsonFile);
+        AxModel readJsonModel = modelReader.read(jsonFileInputStream);
+        jsonFileInputStream.close();
+        assertEquals(basicModel, readJsonModel);
+        assertEquals(intKI91, readJsonModel.getKeyInformation().get("IntegerKIKey91"));
+        assertNotNull(readJsonModel.getKeyInformation().get("FloatKIKey"));
+        tempJsonFile.delete();
     }
 
     private AxModel setTestBasicModel() {
diff --git a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/xml/AxReferenceKeyAdapterTest.java b/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/xml/AxReferenceKeyAdapterTest.java
deleted file mode 100644
index 12a67c803..000000000
--- a/model/basic-model/src/test/java/org/onap/policy/apex/model/basicmodel/xml/AxReferenceKeyAdapterTest.java
+++ /dev/null
@@ -1,42 +0,0 @@
-/*
- * ============LICENSE_START=======================================================
- *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
- * ================================================================================
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- * 
- *      http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- * 
- * SPDX-License-Identifier: Apache-2.0
- * ============LICENSE_END=========================================================
- */
-
-package org.onap.policy.apex.model.basicmodel.xml;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotNull;
-
-import org.junit.Test;
-import org.onap.policy.apex.model.basicmodel.concepts.AxReferenceKey;
-
-public class AxReferenceKeyAdapterTest {
-
-    @Test
-    public void test() throws Exception {
-        AxReferenceKeyAdapter arka = new AxReferenceKeyAdapter();
-        assertNotNull(arka);
-        
-        AxReferenceKey rkey = new AxReferenceKey("Name", "0.0.1", "PLN", "LN");
-        
-        String rkeyString = arka.marshal(rkey);
-        assertEquals("LN", rkeyString);
-        assertEquals(rkey.getLocalName(), arka.unmarshal(rkeyString).getLocalName());
-    }
-}