Add superclasses for gson-jackson migration

Added common classes needed by other gson-jackson code.
Modified some logic to make it more maintainable or perform better.
Updated comments and spacing.
Fix another comment.
Moved gson classes from utils to a separate gson project.
Added GsonXxx annotations to mirror jackson annotations.
Removed unneeded dependencies from gson pom.
Removed old GsonMessage class from policy-endpoints.
Removed trailing spaces.
Updated licenses.
Removed more trailing spaces.
Removed unneeded checkstyle suppression file from utils.

Change-Id: I1a285500faeb0a0b6a1467d09b92ecd3cded713e
Issue-ID: POLICY-1428
Signed-off-by: Jim Hahn <jrh3@att.com>

1 files changed, 387 insertions, 0 deletions

diff --git a/gson/src/test/java/org/onap/policy/common/gson/internal/AdapterTest.java b/gson/src/test/java/org/onap/policy/common/gson/internal/AdapterTest.java
new file mode 100644
index 00000000..fcb0d9ad
--- /dev/null
+++ b/gson/src/test/java/org/onap/policy/common/gson/internal/AdapterTest.java
@@ -0,0 +1,387 @@
+/*
+ * ============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 static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonPrimitive;
+import java.lang.reflect.Field;
+import java.lang.reflect.Method;
+import java.util.List;
+import org.junit.Test;
+import org.onap.policy.common.gson.JacksonExclusionStrategy;
+import org.onap.policy.common.gson.annotation.GsonJsonProperty;
+import org.onap.policy.common.gson.internal.Adapter;
+import org.onap.policy.common.gson.internal.DataAdapterFactory.Data;
+import org.onap.policy.common.gson.internal.DataAdapterFactory.DerivedData;
+
+public class AdapterTest {
+    private static final String GET_VALUE_NAME = "getValue";
+    private static final String VALUE_NAME = "value";
+    private static final String MY_NAME = AdapterTest.class.getName();
+
+    private static DataAdapterFactory dataAdapter = new DataAdapterFactory();
+
+    private static Gson gson = new GsonBuilder().registerTypeAdapterFactory(dataAdapter)
+                    .setExclusionStrategies(new JacksonExclusionStrategy()).create();
+
+    /*
+     * The remaining fields are just used within the tests.
+     */
+
+    private String value;
+
+    // empty alias - should use field name
+    @GsonJsonProperty("")
+    protected String emptyAlias;
+
+    @GsonJsonProperty("name-with-alias")
+    protected String nameWithAlias;
+
+    protected String unaliased;
+
+    protected String $invalidFieldName;
+
+    private List<Data> listField;
+
+    private Data dataField;
+
+
+    @Test
+    public void testIsManagedField() {
+        assertTrue(Adapter.isManaged(field(VALUE_NAME)));
+
+        assertFalse(Adapter.isManaged(field("$invalidFieldName")));
+    }
+
+    @Test
+    public void testIsManagedMethod() {
+        assertTrue(Adapter.isManaged(mget(GET_VALUE_NAME)));
+
+        assertFalse(Adapter.isManaged(mget("get$InvalidName")));
+        assertFalse(Adapter.isManaged(mset("set$InvalidName")));
+    }
+
+    @Test
+    public void testAdapterField_Converter() {
+        Adapter adapter = new Adapter(gson, field("dataField"));
+
+        // first, write something of type Data
+        dataAdapter.reset();
+        dataField = new Data(300);
+        JsonElement tree = adapter.toJsonTree(dataField);
+        assertEquals("{'id':300}".replace('\'', '"'), tree.toString());
+
+        // now try a subclass
+        dataAdapter.reset();
+        dataField = new DerivedData(300, "three");
+        tree = adapter.toJsonTree(dataField);
+        assertEquals("{'id':300,'text':'three'}".replace('\'', '"'), tree.toString());
+    }
+
+    @Test
+    @SuppressWarnings("unchecked")
+    public void testAdapterField_Converter_List() {
+        listField = DataAdapterFactory.makeList();
+
+        Adapter adapter = new Adapter(gson, field("listField"));
+
+        dataAdapter.reset();
+        JsonElement tree = adapter.toJsonTree(listField);
+        assertTrue(dataAdapter.isDataWritten());
+        assertEquals(DataAdapterFactory.ENCODED_LIST, tree.toString());
+
+        // encode it twice so it uses the cached converter
+        dataAdapter.reset();
+        tree = adapter.toJsonTree(listField);
+        assertTrue(dataAdapter.isDataWritten());
+        assertEquals(DataAdapterFactory.ENCODED_LIST, tree.toString());
+
+        dataAdapter.reset();
+        List<Data> lst2 = (List<Data>) adapter.fromJsonTree(tree);
+        assertTrue(dataAdapter.isDataRead());
+
+        assertEquals(listField.toString(), lst2.toString());
+
+        // decode it twice so it uses the cached converter
+        dataAdapter.reset();
+        lst2 = (List<Data>) adapter.fromJsonTree(tree);
+        assertTrue(dataAdapter.isDataRead());
+
+        assertEquals(listField.toString(), lst2.toString());
+    }
+
+    @Test
+    public void testAdapterMethod_Converter() throws Exception {
+        listField = DataAdapterFactory.makeList();
+
+        Method getter = mget("getMyList");
+
+        Adapter aget = new Adapter(gson, getter, true, getter.getReturnType());
+
+        dataAdapter.reset();
+        JsonElement tree = aget.toJsonTree(listField);
+        assertTrue(dataAdapter.isDataWritten());
+        assertEquals(DataAdapterFactory.ENCODED_LIST, tree.toString());
+
+        Method setter = AdapterTest.class.getDeclaredMethod("setMyList", List.class);
+        Adapter aset = new Adapter(gson, setter, true, setter.getGenericParameterTypes()[0]);
+
+        dataAdapter.reset();
+        @SuppressWarnings("unchecked")
+        List<Data> lst2 = (List<Data>) aset.fromJsonTree(tree);
+        assertTrue(dataAdapter.isDataRead());
+
+        assertEquals(listField.toString(), lst2.toString());
+    }
+
+    @Test
+    public void testGetPropName_testGetFullName_testMakeError() {
+        // test field
+        Adapter adapter = new Adapter(gson, field(VALUE_NAME));
+
+        assertEquals(VALUE_NAME, adapter.getPropName());
+        assertEquals(MY_NAME + ".value", adapter.getFullName());
+
+
+        // test getter
+        adapter = new Adapter(gson, mget(GET_VALUE_NAME), true, String.class);
+
+        assertEquals(VALUE_NAME, adapter.getPropName());
+        assertEquals(MY_NAME + ".getValue", adapter.getFullName());
+
+        assertEquals("hello: " + MY_NAME + ".getValue", adapter.makeError("hello: "));
+
+
+        // test setter
+        adapter = new Adapter(gson, mset("setValue"), false, String.class);
+
+        assertEquals(VALUE_NAME, adapter.getPropName());
+        assertEquals(MY_NAME + ".setValue", adapter.getFullName());
+    }
+
+    @Test
+    public void testToJsonTree() {
+        Adapter adapter = new Adapter(gson, field(VALUE_NAME));
+
+        JsonElement tree = adapter.toJsonTree("hello");
+        assertTrue(tree.isJsonPrimitive());
+        assertEquals("hello", tree.getAsString());
+    }
+
+    @Test
+    public void testFromJsonTree() {
+        Adapter adapter = new Adapter(gson, field(VALUE_NAME));
+
+        assertEquals("world", adapter.fromJsonTree(new JsonPrimitive("world")));
+    }
+
+    @Test
+    public void testDetmPropName() {
+        assertEquals("emptyAlias", Adapter.detmPropName(field("emptyAlias")));
+        assertEquals("name-with-alias", Adapter.detmPropName(field("nameWithAlias")));
+        assertEquals("unaliased", Adapter.detmPropName(field("unaliased")));
+        assertEquals(null, Adapter.detmPropName(field("$invalidFieldName")));
+    }
+
+    @Test
+    public void testDetmGetterPropName() {
+        assertEquals("emptyAlias", Adapter.detmGetterPropName(mget("getEmptyAlias")));
+        assertEquals("get-with-alias", Adapter.detmGetterPropName(mget("getWithAlias")));
+        assertEquals("plain", Adapter.detmGetterPropName(mget("getPlain")));
+        assertEquals("primBool", Adapter.detmGetterPropName(mget("isPrimBool")));
+        assertEquals("boxedBool", Adapter.detmGetterPropName(mget("isBoxedBool")));
+        assertEquals(null, Adapter.detmGetterPropName(mget("isString")));
+        assertEquals(null, Adapter.detmGetterPropName(mget("noGet")));
+        assertEquals(null, Adapter.detmGetterPropName(mget("get")));
+        assertEquals(null, Adapter.detmGetterPropName(mget("get$InvalidName")));
+    }
+
+    @Test
+    public void testDetmSetterPropName() {
+        assertEquals("emptyAlias", Adapter.detmSetterPropName(mset("setEmptyAlias")));
+        assertEquals("set-with-alias", Adapter.detmSetterPropName(mset("setWithAlias")));
+        assertEquals("plain", Adapter.detmSetterPropName(mset("setPlain")));
+        assertEquals(null, Adapter.detmSetterPropName(mset("noSet")));
+        assertEquals(null, Adapter.detmSetterPropName(mset("set")));
+        assertEquals(null, Adapter.detmSetterPropName(mset("set$InvalidName")));
+    }
+
+    @Test
+    public void testGetQualifiedNameField() throws Exception {
+        assertEquals(MY_NAME + ".value", Adapter.getQualifiedName(AdapterTest.class.getDeclaredField(VALUE_NAME)));
+    }
+
+    @Test
+    public void testGetQualifiedNameMethod() throws Exception {
+        assertEquals(MY_NAME + ".getValue", Adapter.getQualifiedName(mget(GET_VALUE_NAME)));
+    }
+
+    /**
+     * Gets a field from this class, by name.
+     *
+     * @param name name of the field to get
+     * @return the field
+     */
+    private Field field(String name) {
+        try {
+            return AdapterTest.class.getDeclaredField(name);
+
+        } catch (SecurityException | NoSuchFieldException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    /**
+     * Gets a "getter" method from this class, by name.
+     *
+     * @param name name of the method to get
+     * @return the method
+     */
+    private Method mget(String name) {
+        try {
+            return AdapterTest.class.getDeclaredMethod(name);
+
+        } catch (NoSuchMethodException | SecurityException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    /**
+     * Gets a "setter" method from this class, by name.
+     *
+     * @param name name of the method to get
+     * @return the method
+     */
+    private Method mset(String name) {
+        try {
+            return AdapterTest.class.getDeclaredMethod(name, String.class);
+
+        } catch (NoSuchMethodException | SecurityException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    /*
+     * The remaining methods are just used within the tests.
+     */
+
+    protected String getValue() {
+        return value;
+    }
+
+    // empty alias - should use method name
+    @GsonJsonProperty("")
+    protected String getEmptyAlias() {
+        return "";
+    }
+
+    @GsonJsonProperty("get-with-alias")
+    protected String getWithAlias() {
+        return "";
+    }
+
+    // no alias, begins with "get"
+    protected String getPlain() {
+        return "";
+    }
+
+    // begins with "is", returns primitive boolean
+    protected boolean isPrimBool() {
+        return true;
+    }
+
+    // begins with "is", returns boxed Boolean
+    protected Boolean isBoxedBool() {
+        return true;
+    }
+
+    // begins with "is", but doesn't return a boolean
+    protected String isString() {
+        return "";
+    }
+
+    // doesn't begin with "get"
+    protected String noGet() {
+        return "";
+    }
+
+    // nothing after "get"
+    protected String get() {
+        return "";
+    }
+
+    // name has a bogus character
+    protected String get$InvalidName() {
+        return "";
+    }
+
+
+    protected void setValue(String text) {
+        // do nothing
+    }
+
+    // empty alias - should use method name
+    @GsonJsonProperty("")
+    protected void setEmptyAlias(String text) {
+        // do nothing
+    }
+
+    @GsonJsonProperty("set-with-alias")
+    protected void setWithAlias(String text) {
+        // do nothing
+    }
+
+    // no alias, begins with "set"
+    protected void setPlain(String text) {
+        // do nothing
+    }
+
+    // doesn't begin with "set"
+    protected void noSet(String text) {
+        // do nothing
+    }
+
+    // nothing after "get"
+    protected void set(String text) {
+        // do nothing
+    }
+
+    // name has a bogus character
+    protected void set$InvalidName(String text) {
+        // do nothing
+    }
+
+    // returns a list
+    protected List<Data> getMyList() {
+        return listField;
+    }
+
+    // accepts a list
+    protected void setMyList(List<Data> newList) {
+        listField = newList;
+    }
+}