JsonbTypeAdapter is now allowed on the creator paramters (#291)

Signed-off-by: David Kral <david.k.kral@oracle.com>

api/src/main/java/jakarta/json/bind/annotation/JsonbTypeAdapter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, 2020 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2016, 2021 Oracle and/or its affiliates. All rights reserved.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -32,13 +32,14 @@
  *   <li> type </li>
  *   <li> field </li>
  *   <li> method </li>
+ *   <li> parameter </li>
  * </ul>
  *
  * @since JSON Binding 1.0
  */
 @JsonbAnnotation
 @Retention(RetentionPolicy.RUNTIME)
-@Target({ElementType.ANNOTATION_TYPE, ElementType.TYPE, ElementType.FIELD, ElementType.METHOD})
+@Target({ElementType.ANNOTATION_TYPE, ElementType.TYPE, ElementType.FIELD, ElementType.METHOD, ElementType.PARAMETER})
 public @interface JsonbTypeAdapter {
 
     /**

spec/src/main/asciidoc/jsonb.adoc

@@ -706,6 +706,8 @@ There are two ways how to register `JsonbAdapter`:
 
 `JsonbAdapter` registered via `JsonbConfig::withAdapters` is visible to all serialize/deserialize operations performed with given `JsonbConfig`. `JsonbAdapter` registered with annotation is visible to serialize/deserialize operation used only for annotated field.
 
+It is possible to annotate `JsonbCreator` parameter with `JsonbTypeAdapter` and provide adapter for a parameter this way. However, if `JsonbTypeAdapter` annotation is provided to any other parameter (such as setter method parameter) it will be ignored.
+
 Implementations must provide a CDI support in adapters to allow injection of CDI managed beans into it.
 
 ==== Serializers/Deserializers
@@ -722,7 +724,7 @@ There are two ways how to register `JsonbSerializer/JsonbDeserializer`:
 . Using `JsonbConfig::withSerializers/ JsonbConfig::withDeserializers` method;
 . Annotating a type with `JsonbSerializer/JsonbDeserializer` annotation.
 
-It is possible to annotate `JsonbCreator` parameters with `JsonbTypeDeserializer` and provide deserializer for a parameter this way. However, if `JsonbTypeDeserializer` annotation is provided to any other parameter (such as setter method parameter) it will be ignored.
+It is possible to annotate `JsonbCreator` parameter with `JsonbTypeDeserializer` and provide deserializer for a parameter this way. However, if `JsonbTypeDeserializer` annotation is provided to any other parameter (such as setter method parameter) it will be ignored.
 
 Implementations must provide a CDI support in serializers/deserializers to allow injection of CDI managed beans into it.
 

tck/src/main/java/jakarta/json/bind/tck/customizedmapping/instantiation/InstantiationCustomizationTest.java

@@ -21,6 +21,7 @@
 package jakarta.json.bind.tck.customizedmapping.instantiation;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.fail;
 
 import java.lang.invoke.MethodHandles;
@@ -36,6 +37,7 @@
 import jakarta.json.bind.JsonbBuilder;
 import jakarta.json.bind.JsonbException;
 import jakarta.json.bind.tck.customizedmapping.instantiation.model.CreatorPlusFactoryContainer;
+import jakarta.json.bind.tck.customizedmapping.instantiation.model.CreatorWithAdapterContainer;
 import jakarta.json.bind.tck.customizedmapping.instantiation.model.CreatorWithDeserializerContainer;
 import jakarta.json.bind.tck.customizedmapping.instantiation.model.IllegalInstanceFactoryCreatorContainer;
 import jakarta.json.bind.tck.customizedmapping.instantiation.model.MultipleCreatorsContainer;
@@ -248,4 +250,14 @@ public void testJsonbDeserializerOnCreatorParameter() {
     String expected = "Test String Deserialized";
     assertEquals("JsonbDeserializer on the JsonbCreator parameter was not executed." , expected, c.getStringInstance());
   }
+
+  @Test
+  public void testJsonbAdapterOnCreatorParameter() {
+    CreatorWithAdapterContainer c = jsonb.fromJson("{ \"instance\" : \"string value\" }",
+                                                   CreatorWithAdapterContainer.class);
+    String expected = "string value";
+    assertNotNull("JsonbAdapter on the JsonbCreator parameter was not executed.", c.getStringWrapper());
+    assertEquals("JsonbAdapter on the JsonbCreator parameter was not executed.",
+                 expected, c.getStringWrapper().getWrapped());
+  }
 }

tck/src/main/java/jakarta/json/bind/tck/customizedmapping/instantiation/model/CreatorWithAdapterContainer.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2021 Oracle and/or its affiliates. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0, which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * This Source Code may also be made available under the following Secondary
+ * Licenses when the conditions for such availability set forth in the
+ * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
+ * version 2 with the GNU Classpath Exception, which is available at
+ * https://www.gnu.org/software/classpath/license.html.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
+ */
+
+package jakarta.json.bind.tck.customizedmapping.instantiation.model;
+
+import jakarta.json.bind.adapter.JsonbAdapter;
+import jakarta.json.bind.annotation.JsonbCreator;
+import jakarta.json.bind.annotation.JsonbProperty;
+import jakarta.json.bind.annotation.JsonbTypeAdapter;
+
+public class CreatorWithAdapterContainer {
+
+    private final StringWrapper stringWrapper;
+
+    @JsonbCreator
+    public CreatorWithAdapterContainer(@JsonbProperty("instance")
+                                       @JsonbTypeAdapter(SimpleStringAdapter.class) StringWrapper stringWrapper) {
+        this.stringWrapper = stringWrapper;
+    }
+
+    public StringWrapper getStringWrapper() {
+        return stringWrapper;
+    }
+
+    public static class StringWrapper {
+
+        private final String wrapped;
+
+        private StringWrapper(String wrapped) {
+            this.wrapped = wrapped;
+        }
+
+        public String getWrapped() {
+            return wrapped;
+        }
+
+    }
+
+    public static class SimpleStringAdapter implements JsonbAdapter<StringWrapper, String> {
+
+        @Override
+        public String adaptToJson(StringWrapper obj) {
+            return obj.getWrapped();
+        }
+
+        @Override
+        public StringWrapper adaptFromJson(String obj) {
+            return new StringWrapper(obj);
+        }
+    }
+
+}