Add merge utility for service templates

This utility function allows a TOSCA service template fragment to be
merged with an exsiting service template and will be tbe backbone of
"create" methods on the API from now on.

Issue-ID: POLICY-1402
Change-Id: I3381cb2a1bd30621a639dedc213c546eeb2bf9aa
Signed-off-by: liamfallon <liam.fallon@est.tech>

7 files changed, 424 insertions, 44 deletions

diff --git a/models-base/src/main/java/org/onap/policy/models/base/PfConceptContainer.java b/models-base/src/main/java/org/onap/policy/models/base/PfConceptContainer.java
index 2ecf8c1c6..949cb96dc 100644
--- a/models-base/src/main/java/org/onap/policy/models/base/PfConceptContainer.java
+++ b/models-base/src/main/java/org/onap/policy/models/base/PfConceptContainer.java
@@ -234,10 +234,7 @@ public class PfConceptContainer<C extends PfConcept, A extends PfNameVersion> ex
 
         result = key.validate(result);
 
-        if (conceptMap.isEmpty()) {
-            result.addValidationMessage(new PfValidationMessage(key, this.getClass(), ValidationResult.INVALID,
-                    "conceptMap may not be empty"));
-        } else {
+        if (!conceptMap.isEmpty()) {
             result = validateConceptMap(result);
         }
 
diff --git a/models-base/src/test/java/org/onap/policy/models/base/PfConceptContainerTest.java b/models-base/src/test/java/org/onap/policy/models/base/PfConceptContainerTest.java
index 5e84dff9a..b760e17c0 100644
--- a/models-base/src/test/java/org/onap/policy/models/base/PfConceptContainerTest.java
+++ b/models-base/src/test/java/org/onap/policy/models/base/PfConceptContainerTest.java
@@ -1,6 +1,6 @@
 /*-
  * ============LICENSE_START=======================================================
- *  Copyright (C) 2019 Nordix Foundation.
+ *  Copyright (C) 2019-2020 Nordix Foundation.
  *  Modifications Copyright (C) 2019 AT&T Intellectual Property. All rights reserved.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -33,6 +33,7 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.TreeMap;
+
 import org.junit.Test;
 import org.onap.policy.models.base.testconcepts.DummyAuthorativeConcept;
 import org.onap.policy.models.base.testconcepts.DummyBadPfConceptContainer;
@@ -54,7 +55,7 @@ public class PfConceptContainerTest {
     private static final String DUMMY_VALUE = "Dummy";
     private static final String VERSION0 = "0.0.1";
 
-    @SuppressWarnings({ "unchecked", "rawtypes" })
+    @SuppressWarnings({"unchecked", "rawtypes"})
     @Test
     public void testConceptContainer() {
         DummyPfConceptContainer container = new DummyPfConceptContainer();
@@ -74,10 +75,10 @@ public class PfConceptContainerTest {
         assertThatThrownBy(() -> new DummyPfConceptContainer((PfConceptKey) null, null)).hasMessage(KEY_IS_NULL);
 
         assertThatThrownBy(() -> new DummyPfConceptContainer(new PfConceptKey(), null))
-                        .hasMessage("conceptMap is marked @NonNull but is null");
+                .hasMessage("conceptMap is marked @NonNull but is null");
 
         assertThatThrownBy(() -> new DummyPfConceptContainer(null, new TreeMap<PfConceptKey, DummyPfConcept>()))
-                        .hasMessage(KEY_IS_NULL);
+                .hasMessage(KEY_IS_NULL);
 
         container.getKey().setName(DUMMY_VALUE);
         DummyPfConceptContainer clonedContainer = new DummyPfConceptContainer(container);
@@ -85,7 +86,7 @@ public class PfConceptContainerTest {
         assertEquals(DUMMY_VALUE, clonedContainer.getKey().getName());
 
         assertThatThrownBy(() -> new DummyPfConceptContainer((DummyPfConceptContainer) null))
-                        .hasMessage("copyConcept is marked @NonNull but is null");
+                .hasMessage("copyConcept is marked @NonNull but is null");
 
         List<PfKey> keyList = container.getKeys();
         assertEquals(1, keyList.size());
@@ -114,7 +115,7 @@ public class PfConceptContainerTest {
         assertEquals(0, container.compareTo(clonedContainer));
 
         assertThatThrownBy(() -> new DummyPfConceptContainer((DummyPfConceptContainer) null))
-                        .isInstanceOf(NullPointerException.class);
+                .isInstanceOf(NullPointerException.class);
 
         assertFalse(container.compareTo(null) == 0);
         assertEquals(0, container.compareTo(container));
@@ -136,7 +137,7 @@ public class PfConceptContainerTest {
         DummyPfConceptContainer validateContainer = new DummyPfConceptContainer();
         assertFalse(validateContainer.validate(new PfValidationResult()).isOk());
         validateContainer.setKey(new PfConceptKey("VCKey", VERSION0));
-        assertFalse(validateContainer.validate(new PfValidationResult()).isOk());
+        assertTrue(validateContainer.validate(new PfValidationResult()).isOk());
 
         validateContainer.getConceptMap().put(testConceptKey, new DummyPfConcept(testConceptKey));
         assertTrue(validateContainer.validate(new PfValidationResult()).isOk());
@@ -194,11 +195,11 @@ public class PfConceptContainerTest {
 
         DummyBadPfConceptContainer badContainer = new DummyBadPfConceptContainer();
         assertThatThrownBy(() -> badContainer.fromAuthorative(authorativeList))
-                        .hasMessage("failed to instantiate instance of container concept class");
+                .hasMessage("failed to instantiate instance of container concept class");
 
         authorativeList.clear();
         assertThatThrownBy(() -> container.fromAuthorative(authorativeList))
-                        .hasMessage("An incoming list of concepts must have at least one entry");
+                .hasMessage("An incoming list of concepts must have at least one entry");
     }
 
     @Test(expected = NullPointerException.class)
diff --git a/models-tosca/src/main/java/org/onap/policy/models/tosca/simple/concepts/JpaToscaServiceTemplate.java b/models-tosca/src/main/java/org/onap/policy/models/tosca/simple/concepts/JpaToscaServiceTemplate.java
index 31c7df047..f6139ab2d 100644
--- a/models-tosca/src/main/java/org/onap/policy/models/tosca/simple/concepts/JpaToscaServiceTemplate.java
+++ b/models-tosca/src/main/java/org/onap/policy/models/tosca/simple/concepts/JpaToscaServiceTemplate.java
@@ -277,26 +277,13 @@ public class JpaToscaServiceTemplate extends JpaToscaEntityType<ToscaServiceTemp
 
     @Override
     public int compareTo(final PfConcept otherConcept) {
-        if (otherConcept == null) {
-            return -1;
-        }
-        if (this == otherConcept) {
-            return 0;
-        }
-        if (getClass() != otherConcept.getClass()) {
-            return getClass().getName().compareTo(otherConcept.getClass().getName());
-        }
-
-        final JpaToscaServiceTemplate other = (JpaToscaServiceTemplate) otherConcept;
-        if (!super.equals(other)) {
-            return super.compareTo(other);
-        }
-
-        int result = ObjectUtils.compare(toscaDefinitionsVersion, other.toscaDefinitionsVersion);
+        int result = compareToWithoutEntities(otherConcept);
         if (result != 0) {
             return result;
         }
 
+        final JpaToscaServiceTemplate other = (JpaToscaServiceTemplate) otherConcept;
+
         result = ObjectUtils.compare(dataTypes, other.dataTypes);
         if (result != 0) {
             return result;
@@ -309,4 +296,29 @@ public class JpaToscaServiceTemplate extends JpaToscaEntityType<ToscaServiceTemp
 
         return ObjectUtils.compare(topologyTemplate, other.topologyTemplate);
     }
+
+    /**
+     * Compare this service template to another service template, ignoring contained entitites.
+     *
+     * @param otherConcept the other topology template
+     * @return the result of the comparison
+     */
+    public int compareToWithoutEntities(final PfConcept otherConcept) {
+        if (otherConcept == null) {
+            return -1;
+        }
+        if (this == otherConcept) {
+            return 0;
+        }
+        if (getClass() != otherConcept.getClass()) {
+            return getClass().getName().compareTo(otherConcept.getClass().getName());
+        }
+
+        final JpaToscaServiceTemplate other = (JpaToscaServiceTemplate) otherConcept;
+        if (!super.equals(other)) {
+            return super.compareTo(other);
+        }
+
+        return ObjectUtils.compare(toscaDefinitionsVersion, other.toscaDefinitionsVersion);
+    }
 }
diff --git a/models-tosca/src/main/java/org/onap/policy/models/tosca/simple/concepts/JpaToscaTopologyTemplate.java b/models-tosca/src/main/java/org/onap/policy/models/tosca/simple/concepts/JpaToscaTopologyTemplate.java
index 5fd1a498c..c8dfa5a36 100644
--- a/models-tosca/src/main/java/org/onap/policy/models/tosca/simple/concepts/JpaToscaTopologyTemplate.java
+++ b/models-tosca/src/main/java/org/onap/policy/models/tosca/simple/concepts/JpaToscaTopologyTemplate.java
@@ -1,6 +1,6 @@
 /*-
  * ============LICENSE_START=======================================================
- *  Copyright (C) 2019 Nordix Foundation.
+ *  Copyright (C) 2019-2020 Nordix Foundation.
  *  Modifications Copyright (C) 2019 AT&T Intellectual Property. All rights reserved.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -22,6 +22,7 @@
 package org.onap.policy.models.tosca.simple.concepts;
 
 import java.util.List;
+
 import javax.persistence.CascadeType;
 import javax.persistence.Column;
 import javax.persistence.EmbeddedId;
@@ -31,9 +32,11 @@ import javax.persistence.Inheritance;
 import javax.persistence.InheritanceType;
 import javax.persistence.OneToOne;
 import javax.persistence.Table;
+
 import lombok.Data;
 import lombok.EqualsAndHashCode;
 import lombok.NonNull;
+
 import org.apache.commons.lang3.ObjectUtils;
 import org.onap.policy.models.base.PfAuthorative;
 import org.onap.policy.models.base.PfConcept;
@@ -78,8 +81,7 @@ public class JpaToscaTopologyTemplate extends PfConcept implements PfAuthorative
     }
 
     /**
-     * The Key Constructor creates a {@link JpaToscaTopologyTemplate} object with the given concept
-     * key.
+     * The Key Constructor creates a {@link JpaToscaTopologyTemplate} object with the given concept key.
      *
      * @param key the key
      */
@@ -178,6 +180,21 @@ public class JpaToscaTopologyTemplate extends PfConcept implements PfAuthorative
 
     @Override
     public int compareTo(final PfConcept otherConcept) {
+        int result = compareToWithoutEntities(otherConcept);
+        if (result != 0) {
+            return result;
+        }
+
+        return ObjectUtils.compare(policies, ((JpaToscaTopologyTemplate) otherConcept).policies);
+    }
+
+    /**
+     * Compare this topology template to another topology template, ignoring contained entitites.
+     *
+     * @param otherConcept the other topology template
+     * @return the result of the comparison
+     */
+    public int compareToWithoutEntities(final PfConcept otherConcept) {
         if (otherConcept == null) {
             return -1;
         }
@@ -193,11 +210,6 @@ public class JpaToscaTopologyTemplate extends PfConcept implements PfAuthorative
             return key.compareTo(other.key);
         }
 
-        int result = ObjectUtils.compare(description, other.description);
-        if (result != 0) {
-            return result;
-        }
-
-        return ObjectUtils.compare(policies, other.policies);
+        return ObjectUtils.compare(description, other.description);
     }
 }
diff --git a/models-tosca/src/main/java/org/onap/policy/models/tosca/utils/ToscaServiceTemplateUtils.java b/models-tosca/src/main/java/org/onap/policy/models/tosca/utils/ToscaServiceTemplateUtils.java
new file mode 100644
index 000000000..343e02300
--- /dev/null
+++ b/models-tosca/src/main/java/org/onap/policy/models/tosca/utils/ToscaServiceTemplateUtils.java
@@ -0,0 +1,152 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * Copyright (C) 2020 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.models.tosca.utils;
+
+import java.util.Map;
+import java.util.Map.Entry;
+
+import javax.ws.rs.core.Response;
+
+import lombok.NonNull;
+
+import org.onap.policy.models.base.PfConceptContainer;
+import org.onap.policy.models.base.PfConceptKey;
+import org.onap.policy.models.base.PfModelRuntimeException;
+import org.onap.policy.models.base.PfValidationMessage;
+import org.onap.policy.models.base.PfValidationResult;
+import org.onap.policy.models.base.PfValidationResult.ValidationResult;
+import org.onap.policy.models.tosca.authorative.concepts.ToscaEntity;
+import org.onap.policy.models.tosca.simple.concepts.JpaToscaEntityType;
+import org.onap.policy.models.tosca.simple.concepts.JpaToscaServiceTemplate;
+import org.onap.policy.models.tosca.simple.concepts.JpaToscaTopologyTemplate;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * This utility class provides methods to manage service templates.
+ */
+public class ToscaServiceTemplateUtils {
+    private static final Logger LOGGER = LoggerFactory.getLogger(ToscaServiceTemplateUtils.class);
+
+    /**
+     * Private constructor to prevent subclassing.
+     */
+    private ToscaServiceTemplateUtils() {
+        // Private constructor to prevent subclassing
+    }
+
+    /**
+     * Add a service template fragment to a service template. All entities in the service template fragment must either
+     * a) not exist on the original service template or b) be identical to entities on the original service template.
+     *
+     * @param originalTemplate the original service template
+     * @param fragmentTemplate the fragment being added to the original service template
+     * @return
+     */
+    public static JpaToscaServiceTemplate addFragment(@NonNull final JpaToscaServiceTemplate originalTemplate,
+            @NonNull final JpaToscaServiceTemplate fragmentTemplate) {
+        PfValidationResult result = new PfValidationResult();
+
+        if (originalTemplate.compareToWithoutEntities(fragmentTemplate) != 0) {
+            result.addValidationMessage(new PfValidationMessage(originalTemplate.getKey(),
+                    ToscaServiceTemplateUtils.class, ValidationResult.INVALID,
+                    "service template in incoming fragment does not equal existing service template"));
+        }
+
+        JpaToscaServiceTemplate compositeTemplate = new JpaToscaServiceTemplate(originalTemplate);
+
+        compositeTemplate.setDataTypes(
+                addFragmentEntitites(compositeTemplate.getDataTypes(), fragmentTemplate.getDataTypes(), result));
+        compositeTemplate.setPolicyTypes(
+                addFragmentEntitites(compositeTemplate.getPolicyTypes(), fragmentTemplate.getPolicyTypes(), result));
+
+        if (originalTemplate.getTopologyTemplate() != null) {
+            if (originalTemplate.getTopologyTemplate()
+                    .compareToWithoutEntities(fragmentTemplate.getTopologyTemplate()) == 0) {
+                compositeTemplate.getTopologyTemplate()
+                        .setPolicies(addFragmentEntitites(compositeTemplate.getTopologyTemplate().getPolicies(),
+                                fragmentTemplate.getTopologyTemplate().getPolicies(), result));
+            } else {
+                result.addValidationMessage(new PfValidationMessage(originalTemplate.getTopologyTemplate().getKey(),
+                        ToscaServiceTemplateUtils.class, ValidationResult.INVALID,
+                        "topology template in incoming fragment does not equal existing topology template"));
+            }
+        } else if (fragmentTemplate.getTopologyTemplate() != null) {
+            compositeTemplate.setTopologyTemplate(new JpaToscaTopologyTemplate(fragmentTemplate.getTopologyTemplate()));
+        }
+
+        if (result.isValid()) {
+            result = compositeTemplate.validate(result);
+        }
+
+        if (!result.isValid()) {
+            String message = result.toString();
+            throw new PfModelRuntimeException(Response.Status.BAD_REQUEST, message);
+        }
+
+        return compositeTemplate;
+    }
+
+    /**
+     * Check entities from a fragment container can be added to an original container.
+     *
+     * @param <S> The type of container
+     *
+     * @param compositeContainer the original container
+     * @param fragmentContainer the fragment being added to the original container
+     * @return the composite container with the result
+     */
+    @SuppressWarnings("unchecked")
+    // @formatter:off
+    private static
+        <S extends PfConceptContainer<? extends JpaToscaEntityType<? extends ToscaEntity>, ? extends ToscaEntity>>
+            S addFragmentEntitites(final S compositeContainer, final S fragmentContainer,
+                    final PfValidationResult result) {
+
+        if (compositeContainer == null) {
+            return fragmentContainer;
+        }
+
+        if (fragmentContainer == null) {
+            return compositeContainer;
+        }
+
+        for (Entry<PfConceptKey, ? extends JpaToscaEntityType<? extends ToscaEntity>> fragmentEntry : fragmentContainer
+                .getConceptMap().entrySet()) {
+            JpaToscaEntityType<? extends ToscaEntity> containerEntry =
+                    compositeContainer.getConceptMap().get(fragmentEntry.getKey());
+            if (containerEntry != null && !containerEntry.equals(fragmentEntry.getValue())) {
+                result.addValidationMessage(new PfValidationMessage(fragmentEntry.getKey(),
+                        ToscaServiceTemplateUtils.class,
+                        ValidationResult.INVALID, "entity in incoming fragment does not equal existing entity"));
+            }
+        }
+
+        // This use of a generic map is required to get around typing errors in directly adding the fragment map to the
+        // original map
+        @SuppressWarnings("rawtypes")
+        Map originalContainerMap = compositeContainer.getConceptMap();
+        originalContainerMap.putAll(fragmentContainer.getConceptMap());
+
+        return compositeContainer;
+    }
+    // @formatter:on
+}
diff --git a/models-tosca/src/test/java/org/onap/policy/models/tosca/simple/concepts/JpaToscaModelTest.java b/models-tosca/src/test/java/org/onap/policy/models/tosca/simple/concepts/JpaToscaModelTest.java
index 74a4e7c7f..839f0f8ca 100644
--- a/models-tosca/src/test/java/org/onap/policy/models/tosca/simple/concepts/JpaToscaModelTest.java
+++ b/models-tosca/src/test/java/org/onap/policy/models/tosca/simple/concepts/JpaToscaModelTest.java
@@ -1,6 +1,6 @@
 /*-
  * ============LICENSE_START=======================================================
- *  Copyright (C) 2019 Nordix Foundation.
+ *  Copyright (C) 2019-2020 Nordix Foundation.
  *  Modifications Copyright (C) 2019 AT&T Intellectual Property. All rights reserved.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -29,6 +29,7 @@ import static org.junit.Assert.assertTrue;
 
 import java.util.Map;
 import java.util.TreeMap;
+
 import org.junit.Test;
 import org.onap.policy.models.base.PfConceptKey;
 import org.onap.policy.models.base.PfModelService;
@@ -58,10 +59,10 @@ public class JpaToscaModelTest {
         assertThatThrownBy(() -> new JpaToscaModel(null, new JpaToscaServiceTemplates())).hasMessage(KEY_IS_NULL);
 
         assertThatThrownBy(() -> new JpaToscaModel(new PfConceptKey(), null))
-                        .hasMessage("serviceTemplates is marked @NonNull but is null");
+                .hasMessage("serviceTemplates is marked @NonNull but is null");
 
         assertThatThrownBy(() -> new JpaToscaModel((JpaToscaModel) null))
-                        .hasMessage("copyConcept is marked @NonNull but is null");
+                .hasMessage("copyConcept is marked @NonNull but is null");
 
         PfConceptKey tstsKey = new PfConceptKey("tsts", VERSION_001);
         Map<PfConceptKey, JpaToscaServiceTemplate> tstMap = new TreeMap<>();
@@ -90,8 +91,7 @@ public class JpaToscaModelTest {
         otherDt.setServiceTemplates(tsts);
         assertEquals(0, tm.compareTo(otherDt));
 
-        assertThatThrownBy(() -> new JpaToscaModel((JpaToscaModel) null))
-                        .isInstanceOf(NullPointerException.class);
+        assertThatThrownBy(() -> new JpaToscaModel((JpaToscaModel) null)).isInstanceOf(NullPointerException.class);
 
         assertEquals(2, tm.getKeys().size());
         assertEquals(2, new JpaToscaModel().getKeys().size());
@@ -101,7 +101,7 @@ public class JpaToscaModelTest {
         assertEquals(tttClone0, tm);
 
         assertFalse(new JpaToscaModel().validate(new PfValidationResult()).isValid());
-        assertFalse(tm.validate(new PfValidationResult()).isValid());
+        assertTrue(tm.validate(new PfValidationResult()).isValid());
 
         tm.register();
         assertTrue(PfModelService.existsModel(tm.getServiceTemplates().getId()));
diff --git a/models-tosca/src/test/java/org/onap/policy/models/tosca/utils/ToscaServiceTemplateUtilsTest.java b/models-tosca/src/test/java/org/onap/policy/models/tosca/utils/ToscaServiceTemplateUtilsTest.java
new file mode 100644
index 000000000..cc6f8f0d0
--- /dev/null
+++ b/models-tosca/src/test/java/org/onap/policy/models/tosca/utils/ToscaServiceTemplateUtilsTest.java
@@ -0,0 +1,206 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2020 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.models.tosca.utils;
+
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+import static org.junit.Assert.assertEquals;
+
+import java.util.Iterator;
+
+import org.junit.Test;
+import org.onap.policy.models.base.PfConceptKey;
+import org.onap.policy.models.tosca.simple.concepts.JpaToscaDataType;
+import org.onap.policy.models.tosca.simple.concepts.JpaToscaDataTypes;
+import org.onap.policy.models.tosca.simple.concepts.JpaToscaPolicies;
+import org.onap.policy.models.tosca.simple.concepts.JpaToscaPolicy;
+import org.onap.policy.models.tosca.simple.concepts.JpaToscaPolicyType;
+import org.onap.policy.models.tosca.simple.concepts.JpaToscaPolicyTypes;
+import org.onap.policy.models.tosca.simple.concepts.JpaToscaServiceTemplate;
+import org.onap.policy.models.tosca.simple.concepts.JpaToscaTopologyTemplate;
+
+/**
+ * Import the {@link ToscaServiceTemplateUtilsTest} class.
+ *
+ * @author Liam Fallon (liam.fallon@est.tech)
+ */
+public class ToscaServiceTemplateUtilsTest {
+    @Test
+    public void testAddFragmentNulls() {
+        assertThatThrownBy(() -> {
+            ToscaServiceTemplateUtils.addFragment(null, null);
+        }).hasMessageMatching("originalTemplate is marked .*on.*ull but is null");
+
+        assertThatThrownBy(() -> {
+            ToscaServiceTemplateUtils.addFragment(null, new JpaToscaServiceTemplate());
+        }).hasMessageMatching("originalTemplate is marked .*on.*ull but is null");
+
+        assertThatThrownBy(() -> {
+            ToscaServiceTemplateUtils.addFragment(new JpaToscaServiceTemplate(), null);
+        }).hasMessageMatching("fragmentTemplate is marked .*on.*ull but is null");
+
+        assertEquals(new JpaToscaServiceTemplate(),
+                ToscaServiceTemplateUtils.addFragment(new JpaToscaServiceTemplate(), new JpaToscaServiceTemplate()));
+    }
+
+    @Test
+    public void testAddFragment() {
+        JpaToscaServiceTemplate originalTemplate = new JpaToscaServiceTemplate();
+        JpaToscaServiceTemplate fragmentTemplate00 = new JpaToscaServiceTemplate();
+
+        assertEquals(originalTemplate, ToscaServiceTemplateUtils.addFragment(originalTemplate, originalTemplate));
+        assertEquals(originalTemplate, ToscaServiceTemplateUtils.addFragment(originalTemplate, fragmentTemplate00));
+        assertEquals(originalTemplate, ToscaServiceTemplateUtils.addFragment(fragmentTemplate00, originalTemplate));
+        assertEquals(originalTemplate, ToscaServiceTemplateUtils.addFragment(fragmentTemplate00, fragmentTemplate00));
+        assertEquals(fragmentTemplate00, ToscaServiceTemplateUtils.addFragment(originalTemplate, originalTemplate));
+        assertEquals(fragmentTemplate00, ToscaServiceTemplateUtils.addFragment(originalTemplate, fragmentTemplate00));
+        assertEquals(fragmentTemplate00, ToscaServiceTemplateUtils.addFragment(fragmentTemplate00, originalTemplate));
+        assertEquals(fragmentTemplate00, ToscaServiceTemplateUtils.addFragment(fragmentTemplate00, fragmentTemplate00));
+
+        fragmentTemplate00.setDataTypes(new JpaToscaDataTypes());
+        fragmentTemplate00.setPolicyTypes(new JpaToscaPolicyTypes());
+
+        JpaToscaServiceTemplate compositeTemplate00 =
+                ToscaServiceTemplateUtils.addFragment(originalTemplate, fragmentTemplate00);
+        assertEquals(compositeTemplate00,
+                ToscaServiceTemplateUtils.addFragment(compositeTemplate00, fragmentTemplate00));
+        assertEquals(compositeTemplate00,
+                ToscaServiceTemplateUtils.addFragment(compositeTemplate00, new JpaToscaServiceTemplate()));
+        assertEquals(compositeTemplate00,
+                ToscaServiceTemplateUtils.addFragment(new JpaToscaServiceTemplate(), compositeTemplate00));
+
+        JpaToscaDataType dt0 = new JpaToscaDataType();
+        dt0.setKey(new PfConceptKey("dt0", "0.0.1"));
+        dt0.setDescription("dt0 description");
+        JpaToscaServiceTemplate fragmentTemplate01 = new JpaToscaServiceTemplate();
+        fragmentTemplate01.setDataTypes(new JpaToscaDataTypes());
+        fragmentTemplate01.getDataTypes().getConceptMap().put(dt0.getKey(), dt0);
+
+        JpaToscaServiceTemplate compositeTemplate01 =
+                ToscaServiceTemplateUtils.addFragment(originalTemplate, fragmentTemplate01);
+        assertEquals(compositeTemplate01,
+                ToscaServiceTemplateUtils.addFragment(compositeTemplate01, fragmentTemplate01));
+        assertEquals(compositeTemplate01,
+                ToscaServiceTemplateUtils.addFragment(compositeTemplate01, new JpaToscaServiceTemplate()));
+        assertEquals(compositeTemplate01,
+                ToscaServiceTemplateUtils.addFragment(new JpaToscaServiceTemplate(), compositeTemplate01));
+
+        JpaToscaServiceTemplate compositeTemplate02 =
+                ToscaServiceTemplateUtils.addFragment(compositeTemplate00, fragmentTemplate01);
+        assertEquals(compositeTemplate02,
+                ToscaServiceTemplateUtils.addFragment(compositeTemplate02, fragmentTemplate01));
+        assertEquals(compositeTemplate02,
+                ToscaServiceTemplateUtils.addFragment(compositeTemplate02, new JpaToscaServiceTemplate()));
+        assertEquals(compositeTemplate02,
+                ToscaServiceTemplateUtils.addFragment(new JpaToscaServiceTemplate(), compositeTemplate02));
+
+        JpaToscaDataType otherDt0 = new JpaToscaDataType();
+        otherDt0.setKey(new PfConceptKey("dt0", "0.0.1"));
+        otherDt0.setDescription("dt0 description");
+        JpaToscaServiceTemplate fragmentTemplate02 = new JpaToscaServiceTemplate();
+        fragmentTemplate02.setDataTypes(new JpaToscaDataTypes());
+        fragmentTemplate02.getDataTypes().getConceptMap().put(otherDt0.getKey(), otherDt0);
+
+        compositeTemplate00 = ToscaServiceTemplateUtils.addFragment(compositeTemplate00, fragmentTemplate02);
+        assertEquals(compositeTemplate00,
+                ToscaServiceTemplateUtils.addFragment(compositeTemplate00, fragmentTemplate02));
+
+        JpaToscaDataType badOtherDt0 = new JpaToscaDataType();
+        badOtherDt0.setKey(new PfConceptKey("dt0", "0.0.1"));
+        badOtherDt0.setDescription("dt0 bad description");
+        JpaToscaServiceTemplate fragmentTemplate03 = new JpaToscaServiceTemplate();
+        fragmentTemplate03.setDataTypes(new JpaToscaDataTypes());
+        fragmentTemplate03.getDataTypes().getConceptMap().put(otherDt0.getKey(), otherDt0);
+        fragmentTemplate03.getDataTypes().getConceptMap().put(badOtherDt0.getKey(), badOtherDt0);
+
+        final JpaToscaServiceTemplate compositeTestTemplate = new JpaToscaServiceTemplate(compositeTemplate00);
+        assertThatThrownBy(() -> {
+            ToscaServiceTemplateUtils.addFragment(compositeTestTemplate, fragmentTemplate03);
+        }).hasMessageContaining("entity in incoming fragment does not equal existing entity");
+
+        JpaToscaServiceTemplate fragmentTemplate04 = new JpaToscaServiceTemplate();
+        fragmentTemplate04.setDescription("Another service template");
+        assertThatThrownBy(() -> {
+            ToscaServiceTemplateUtils.addFragment(compositeTestTemplate, fragmentTemplate04);
+        }).hasMessageContaining("service template in incoming fragment does not equal existing service template");
+
+        JpaToscaServiceTemplate fragmentTemplate05 = new JpaToscaServiceTemplate();
+        fragmentTemplate05.setTopologyTemplate(new JpaToscaTopologyTemplate());
+        fragmentTemplate05.getTopologyTemplate().setDescription("topology template description");
+        JpaToscaServiceTemplate compositeTemplate03 =
+                ToscaServiceTemplateUtils.addFragment(compositeTemplate02, fragmentTemplate05);
+        assertEquals(fragmentTemplate05.getTopologyTemplate(), compositeTemplate03.getTopologyTemplate());
+
+        JpaToscaServiceTemplate fragmentTemplate06 = new JpaToscaServiceTemplate();
+        fragmentTemplate06.setTopologyTemplate(new JpaToscaTopologyTemplate());
+        fragmentTemplate06.getTopologyTemplate().setDescription("topology template description");
+        JpaToscaServiceTemplate compositeTemplate04 =
+                ToscaServiceTemplateUtils.addFragment(compositeTemplate03, fragmentTemplate06);
+        assertEquals(fragmentTemplate06.getTopologyTemplate(), compositeTemplate04.getTopologyTemplate());
+
+        JpaToscaServiceTemplate fragmentTemplate07 = new JpaToscaServiceTemplate();
+        fragmentTemplate07.setTopologyTemplate(new JpaToscaTopologyTemplate());
+        fragmentTemplate07.getTopologyTemplate().setDescription("topology template other description");
+        assertThatThrownBy(() -> {
+            ToscaServiceTemplateUtils.addFragment(compositeTemplate04, fragmentTemplate07);
+        }).hasMessageContaining("topology template in incoming fragment does not equal existing topology template");
+
+        JpaToscaDataType dt1 = new JpaToscaDataType();
+        dt1.setKey(new PfConceptKey("dt1", "0.0.1"));
+        dt1.setDescription("dt1 description");
+
+        JpaToscaPolicyType pt0 = new JpaToscaPolicyType();
+        pt0.setKey(new PfConceptKey("pt0", "0.0.1"));
+        pt0.setDescription("pt0 description");
+
+        JpaToscaPolicy p0 = new JpaToscaPolicy();
+        p0.setKey(new PfConceptKey("p0", "0.0.1"));
+        p0.setDescription("pt0 description");
+
+        JpaToscaServiceTemplate fragmentTemplate08 = new JpaToscaServiceTemplate();
+
+        fragmentTemplate08.setDataTypes(new JpaToscaDataTypes());
+        fragmentTemplate08.getDataTypes().getConceptMap().put(dt1.getKey(), dt1);
+
+        fragmentTemplate08.setPolicyTypes(new JpaToscaPolicyTypes());
+        fragmentTemplate08.getPolicyTypes().getConceptMap().put(pt0.getKey(), pt0);
+
+        fragmentTemplate08.setTopologyTemplate(new JpaToscaTopologyTemplate());
+        fragmentTemplate08.getTopologyTemplate().setDescription("topology template description");
+
+        fragmentTemplate08.getTopologyTemplate().setPolicies(new JpaToscaPolicies());
+        fragmentTemplate08.getTopologyTemplate().getPolicies().getConceptMap().put(p0.getKey(), p0);
+
+        assertThatThrownBy(() -> {
+            ToscaServiceTemplateUtils.addFragment(compositeTemplate04, fragmentTemplate08);
+        }).hasMessageContaining("JpaToscaPolicy:INVALID:type is null or a null key");
+
+        p0.setType(pt0.getKey());
+
+        JpaToscaServiceTemplate compositeTemplate05 =
+                ToscaServiceTemplateUtils.addFragment(compositeTemplate04, fragmentTemplate08);
+        Iterator<JpaToscaDataType> dtIterator = compositeTemplate05.getDataTypes().getAll(null).iterator();
+        assertEquals(dt0, dtIterator.next());
+        assertEquals(dt1, dtIterator.next());
+        assertEquals(pt0, compositeTemplate05.getPolicyTypes().getAll(null).iterator().next());
+        assertEquals(p0, compositeTemplate05.getTopologyTemplate().getPolicies().getAll(null).iterator().next());
+
+    }
+}