Merge "Add jackson behavior for methods"

8 files changed, 577 insertions, 4 deletions

diff --git a/gson/src/main/java/org/onap/policy/common/gson/JacksonMethodAdapterFactory.java b/gson/src/main/java/org/onap/policy/common/gson/JacksonMethodAdapterFactory.java
new file mode 100644
index 00000000..1c3039f7
--- /dev/null
+++ b/gson/src/main/java/org/onap/policy/common/gson/JacksonMethodAdapterFactory.java
@@ -0,0 +1,202 @@
+/*
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2019 AT&T Intellectual Property. 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.gson;
+
+import com.google.gson.Gson;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.TypeAdapter;
+import com.google.gson.TypeAdapterFactory;
+import com.google.gson.reflect.TypeToken;
+import com.google.gson.stream.JsonReader;
+import com.google.gson.stream.JsonWriter;
+import java.io.IOException;
+import java.lang.reflect.Method;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import org.onap.policy.common.gson.internal.AnyGetterSerializer;
+import org.onap.policy.common.gson.internal.AnySetterDeserializer;
+import org.onap.policy.common.gson.internal.ClassWalker;
+import org.onap.policy.common.gson.internal.Deserializer;
+import org.onap.policy.common.gson.internal.MethodDeserializer;
+import org.onap.policy.common.gson.internal.MethodSerializer;
+import org.onap.policy.common.gson.internal.Serializer;
+
+/**
+ * Factory that serializes/deserializes class methods following the normal behavior of
+ * jackson. Supports the following annotations:
+ * <ul>
+ * <li>GsonJsonIgnore</li>
+ * <li>GsonJsonProperty</li>
+ * <li>GsonJsonAnyGetter</li>
+ * <li>GsonJsonAnySetter</li>
+ * </ul>
+ */
+public class JacksonMethodAdapterFactory implements TypeAdapterFactory {
+
+    @Override
+    public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) {
+        Class<? super T> clazz = type.getRawType();
+
+        if (!JacksonExclusionStrategy.isManaged(clazz)) {
+            return null;
+        }
+
+        ClassWalker data = new ClassWalker();
+        data.walkClassHierarchy(clazz);
+
+        if (data.getInProps(Method.class).isEmpty() && data.getOutProps(Method.class).isEmpty()) {
+            if (data.getAnyGetter() == null && data.getAnySetter() == null) {
+                // no methods to serialize
+                return null;
+            }
+        }
+
+        return new JacksonMethodAdapter<>(gson, data, gson.getDelegateAdapter(this, type));
+    }
+
+    /**
+     * Adapter for a single class.
+     *
+     * @param <T> type of class on which the adapter works
+     */
+    private static class JacksonMethodAdapter<T> extends TypeAdapter<T> {
+
+        /**
+         * Used to create an object of the given class.
+         */
+        private final TypeAdapter<T> delegate;
+
+        /**
+         * Used to serialize/deserialize a JsonElement.
+         */
+        private final TypeAdapter<JsonElement> elementAdapter;
+
+        /**
+         * Serializers for each item within the object.
+         */
+        private final Serializer[] serializers;
+
+        /**
+         * Deserializers for each item within the object.
+         */
+        private final Deserializer[] deserializers;
+
+        /**
+         * Constructs the object.
+         *
+         * @param gson the associated gson object
+         * @param data data used to configure the adapter
+         * @param delegate default constructor for the type
+         */
+        public JacksonMethodAdapter(Gson gson, ClassWalker data, TypeAdapter<T> delegate) {
+            this.delegate = delegate;
+
+            this.elementAdapter = gson.getAdapter(JsonElement.class);
+
+            Set<String> unliftedProps = new HashSet<>();
+            unliftedProps.addAll(data.getInNotIgnored());
+            unliftedProps.addAll(data.getOutNotIgnored());
+
+            // create serializers
+            this.serializers = makeSerializers(gson, data, unliftedProps).toArray(new Serializer[0]);
+
+            // create deserializers
+            this.deserializers = makeDeserializers(gson, data, unliftedProps).toArray(new Deserializer[0]);
+        }
+
+        /**
+         * Creates a complete list of serializers.
+         *
+         * @param gson the associated gson object
+         * @param data data used to configure the serializers
+         * @param unliftedProps properties that should not be lowered by "any-getters"
+         * @return a list of all serializers
+         */
+        private List<Serializer> makeSerializers(Gson gson, ClassWalker data, Set<String> unliftedProps) {
+            List<Serializer> ser = new ArrayList<Serializer>();
+
+            if (data.getAnyGetter() != null) {
+                ser.add(new AnyGetterSerializer(gson, unliftedProps, data.getAnyGetter()));
+            }
+
+            data.getOutProps(Method.class).forEach(method -> ser.add(new MethodSerializer(gson, method)));
+
+            return ser;
+        }
+
+        /**
+         * Creates a complete list of deserializers.
+         *
+         * @param gson the associated gson object
+         * @param data data used to configure the deserializers
+         * @param unliftedProps properties that should not be lifted by "any-setters"
+         * @return a list of all deserializers
+         */
+        private List<Deserializer> makeDeserializers(Gson gson, ClassWalker data, Set<String> unliftedProps) {
+            List<Deserializer> deser = new ArrayList<Deserializer>();
+
+            if (data.getAnySetter() != null) {
+                deser.add(new AnySetterDeserializer(gson, unliftedProps, data.getAnySetter()));
+            }
+
+            data.getInProps(Method.class).forEach(method -> deser.add(new MethodDeserializer(gson, method)));
+
+            return deser;
+        }
+
+        @Override
+        public void write(JsonWriter out, T value) throws IOException {
+            JsonElement tree = delegate.toJsonTree(value);
+
+            if (tree.isJsonObject()) {
+                JsonObject jsonObj = tree.getAsJsonObject();
+
+                // serialize each item from the value into the target tree
+                for (Serializer serializer : serializers) {
+                    serializer.addToTree(value, jsonObj);
+                }
+            }
+
+            elementAdapter.write(out, tree);
+        }
+
+        @Override
+        public T read(JsonReader in) throws IOException {
+            JsonElement tree = elementAdapter.read(in);
+
+            T object = delegate.fromJsonTree(tree);
+
+            if (tree.isJsonObject()) {
+                JsonObject jsonObj = tree.getAsJsonObject();
+
+                // deserialize each item from the tree into the target object
+                for (Deserializer dser : deserializers) {
+                    dser.getFromTree(jsonObj, object);
+                }
+            }
+
+            return object;
+        }
+    }
+}
diff --git a/gson/src/main/java/org/onap/policy/common/gson/internal/Adapter.java b/gson/src/main/java/org/onap/policy/common/gson/internal/Adapter.java
index b4ef53f7..bb8672bb 100644
--- a/gson/src/main/java/org/onap/policy/common/gson/internal/Adapter.java
+++ b/gson/src/main/java/org/onap/policy/common/gson/internal/Adapter.java
@@ -86,12 +86,11 @@ public class Adapter {
      *
      * @param gson Gson object providing type adapters
      * @param accessor method used to access the item from within an object
-     * @param forGetter {@code true} if the name is for a "getter" method, {@code false}
-     *        if for a "setter"
      * @param valueType the class of value on which this operates
      */
-    public Adapter(Gson gson, Method accessor, boolean forGetter, Type valueType) {
-        this.propName = (forGetter ? detmGetterPropName(accessor) : detmSetterPropName(accessor));
+    public Adapter(Gson gson, Method accessor, Type valueType) {
+        boolean forSetter = (accessor.getReturnType() == void.class);
+        this.propName = (forSetter ? detmSetterPropName(accessor) : detmGetterPropName(accessor));
         this.reader = new ConvInfo(TypeToken.get(valueType));
         this.gson = gson;
         this.fullName = getQualifiedName(accessor);
diff --git a/gson/src/main/java/org/onap/policy/common/gson/internal/AnyGetterSerializer.java b/gson/src/main/java/org/onap/policy/common/gson/internal/AnyGetterSerializer.java
new file mode 100644
index 00000000..da9ad173
--- /dev/null
+++ b/gson/src/main/java/org/onap/policy/common/gson/internal/AnyGetterSerializer.java
@@ -0,0 +1,83 @@
+/*
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2019 AT&T Intellectual Property. 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.gson.internal;
+
+import com.google.gson.Gson;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParseException;
+import java.lang.reflect.Method;
+import java.util.Map.Entry;
+import java.util.Set;
+
+/**
+ * Serializer for methods having a JsonAnyGetter annotation.
+ */
+public class AnyGetterSerializer extends Lifter implements Serializer {
+
+    public static final String NOT_AN_OBJECT_ERR = "expecting a JsonObject for ";
+
+    /**
+     * Constructs the object.
+     *
+     * @param gson Gson object providing type adapters
+     * @param propName property name associated with the lifted field
+     * @param unliftedProps property names that should not be lifted
+     * @param getter method used to get the item from within an object
+     */
+    public AnyGetterSerializer(Gson gson, Set<String> unliftedProps, Method getter) {
+        super(gson, unliftedProps, getter, getter.getGenericReturnType());
+    }
+
+    @Override
+    public void addToTree(Object source, JsonObject target) {
+        // get the value from the object
+        Object value = invoke(source);
+        if (value == null) {
+            // nothing to lift
+            return;
+        }
+
+        JsonElement inner = toJsonTree(value);
+        if (!inner.isJsonObject()) {
+            throw new JsonParseException(makeError(NOT_AN_OBJECT_ERR));
+        }
+
+        // lift items from inner into the target
+        copyLiftedItems(inner.getAsJsonObject(), target);
+    }
+
+    /**
+     * Copies lifted items from one tree into another, without removing them from the
+     * source tree.
+     *
+     * @param source tree from which items are to be copied
+     * @param target tree into which items are to be copied
+     */
+    private void copyLiftedItems(JsonObject source, JsonObject target) {
+        for (Entry<String, JsonElement> ent : source.entrySet()) {
+            String name = ent.getKey();
+            if (shouldLift(name)) {
+                target.add(name, ent.getValue());
+            }
+        }
+    }
+}
diff --git a/gson/src/main/java/org/onap/policy/common/gson/internal/AnySetterDeserializer.java b/gson/src/main/java/org/onap/policy/common/gson/internal/AnySetterDeserializer.java
new file mode 100644
index 00000000..85d42dfa
--- /dev/null
+++ b/gson/src/main/java/org/onap/policy/common/gson/internal/AnySetterDeserializer.java
@@ -0,0 +1,58 @@
+/*
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2019 AT&T Intellectual Property. 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.gson.internal;
+
+import com.google.gson.Gson;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import java.lang.reflect.Method;
+import java.util.Map.Entry;
+import java.util.Set;
+
+/**
+ * De-serializer for methods having a JsonAnySetter annotation.
+ */
+public class AnySetterDeserializer extends Lifter implements Deserializer {
+
+    /**
+     * Constructs the object.
+     *
+     * @param gson Gson object providing type adapters
+     * @param unliftedProps property names that should not be lifted
+     * @param getter method used to get the item from within an object
+     */
+    public AnySetterDeserializer(Gson gson, Set<String> unliftedProps, Method setter) {
+        super(gson, unliftedProps, setter, setter.getGenericParameterTypes()[1]);
+    }
+
+    @Override
+    public void getFromTree(JsonObject source, Object target) {
+        for (Entry<String, JsonElement> ent : source.entrySet()) {
+            String name = ent.getKey();
+
+            if (shouldLift(name)) {
+                Object value = fromJsonTree(ent.getValue());
+                invoke(target, name, value);
+            }
+        }
+    }
+
+}
diff --git a/gson/src/main/java/org/onap/policy/common/gson/internal/Lifter.java b/gson/src/main/java/org/onap/policy/common/gson/internal/Lifter.java
new file mode 100644
index 00000000..bb8ec321
--- /dev/null
+++ b/gson/src/main/java/org/onap/policy/common/gson/internal/Lifter.java
@@ -0,0 +1,62 @@
+/*
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2019 AT&T Intellectual Property. 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.gson.internal;
+
+import com.google.gson.Gson;
+import java.lang.reflect.Method;
+import java.lang.reflect.Type;
+import java.util.Set;
+
+/**
+ * Super class of serializers and de-serializers that deal with "lifted" data, that is,
+ * data that is lifted from a nested json object into the containing object.
+ */
+public class Lifter extends MethodAdapter {
+
+    /**
+     * Names of the properties that are <i>not</i> to be lifted.
+     */
+    private final Set<String> unliftedProps;
+
+    /**
+     * Constructs the object.
+     *
+     * @param gson Gson object providing type adapters
+     * @param unliftedProps property names that should not be lifted
+     * @param accessor method used to access the item from within an object
+     * @param type the class of value on which this operates
+     */
+    public Lifter(Gson gson, Set<String> unliftedProps, Method accessor, Type type) {
+        super(gson, accessor, type);
+
+        this.unliftedProps = unliftedProps;
+    }
+
+    /**
+     * Determines if a property should be lifted.
+     *
+     * @param propName the name of the property
+     * @return {@code true} if the property should be lifted, {@code false} otherwise
+     */
+    public boolean shouldLift(String propName) {
+        return !unliftedProps.contains(propName);
+    }
+}
diff --git a/gson/src/main/java/org/onap/policy/common/gson/internal/MethodAdapter.java b/gson/src/main/java/org/onap/policy/common/gson/internal/MethodAdapter.java
new file mode 100644
index 00000000..579864da
--- /dev/null
+++ b/gson/src/main/java/org/onap/policy/common/gson/internal/MethodAdapter.java
@@ -0,0 +1,69 @@
+/*
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2019 AT&T Intellectual Property. 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.gson.internal;
+
+import com.google.gson.Gson;
+import com.google.gson.JsonParseException;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.lang.reflect.Type;
+
+/**
+ * Super class of adapters used to serialize and de-serialize a method.
+ */
+public class MethodAdapter extends Adapter {
+
+    public static final String INVOKE_ERR = "cannot invoke method to serialize/deserialize: ";
+
+    /**
+     * Method used to access the item within an object.
+     */
+    private final Method accessor;
+
+    /**
+     * Constructs the object.
+     *
+     * @param gson Gson object providing type adapters
+     * @param accessor method used to access the item from within an object
+     * @param type the class of value on which this operates
+     */
+    public MethodAdapter(Gson gson, Method accessor, Type type) {
+        super(gson, accessor, type);
+
+        this.accessor = accessor;
+    }
+
+    /**
+     * Invokes the accessor method.
+     *
+     * @param self object on which to invoke the method
+     * @param args arguments to be passed to the method
+     * @return the method's result
+     */
+    public Object invoke(Object self, Object... args) {
+        try {
+            return accessor.invoke(self, args);
+
+        } catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
+            throw new JsonParseException(makeError(INVOKE_ERR), e);
+        }
+    }
+}
diff --git a/gson/src/main/java/org/onap/policy/common/gson/internal/MethodDeserializer.java b/gson/src/main/java/org/onap/policy/common/gson/internal/MethodDeserializer.java
new file mode 100644
index 00000000..bb0724eb
--- /dev/null
+++ b/gson/src/main/java/org/onap/policy/common/gson/internal/MethodDeserializer.java
@@ -0,0 +1,53 @@
+/*
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2019 AT&T Intellectual Property. 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.gson.internal;
+
+import com.google.gson.Gson;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import java.lang.reflect.Method;
+
+/**
+ * De-serializer for methods that are exposed.
+ */
+public class MethodDeserializer extends MethodAdapter implements Deserializer {
+
+    /**
+     * Constructs the object.
+     *
+     * @param gson Gson object providing type adapters
+     * @param setter method used to set the item within an object
+     */
+    public MethodDeserializer(Gson gson, Method setter) {
+        super(gson, setter, setter.getGenericParameterTypes()[0]);
+    }
+
+    @Override
+    public void getFromTree(JsonObject source, Object target) {
+        JsonElement jsonEl = source.get(getPropName());
+        if (jsonEl == null || jsonEl.isJsonNull()) {
+            return;
+        }
+
+        invoke(target, fromJsonTree(jsonEl));
+    }
+
+}
diff --git a/gson/src/main/java/org/onap/policy/common/gson/internal/MethodSerializer.java b/gson/src/main/java/org/onap/policy/common/gson/internal/MethodSerializer.java
new file mode 100644
index 00000000..ab544614
--- /dev/null
+++ b/gson/src/main/java/org/onap/policy/common/gson/internal/MethodSerializer.java
@@ -0,0 +1,47 @@
+/*
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2019 AT&T Intellectual Property. 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.gson.internal;
+
+import com.google.gson.Gson;
+import com.google.gson.JsonObject;
+import java.lang.reflect.Method;
+
+/**
+ * Serializer for methods that are exposed.
+ */
+public class MethodSerializer extends MethodAdapter implements Serializer {
+
+    /**
+     * Constructs the object.
+     *
+     * @param gson Gson object providing type adapters
+     * @param getter method used to get the item from within an object
+     */
+    public MethodSerializer(Gson gson, Method getter) {
+        super(gson, getter, getter.getGenericReturnType());
+    }
+
+    @Override
+    public void addToTree(Object source, JsonObject target) {
+        Object value = invoke(source);
+        target.add(getPropName(), (value == null ? null : toJsonTree(value)));
+    }
+}