Add Jsonb support

Spring Framework 5 will support Jsonb as a HttpMessageConverter, this
commit adds auto-configuration support. Also, support for Jsonb in the
@JsonTest has been added.

This implementation is running against Apache Johnzon

See gh-9648

spring-boot-test/src/main/java/org/springframework/boot/test/json/JsonbTester.java

@@ -0,0 +1,128 @@
+/*
+ * Copyright 2012-2017 the original author or authors.
+ *
+ * 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.
+ */
+
+package org.springframework.boot.test.json;
+
+import java.io.IOException;
+import java.io.Reader;
+
+import javax.json.bind.Jsonb;
+
+import org.springframework.beans.factory.ObjectFactory;
+import org.springframework.core.ResolvableType;
+import org.springframework.util.Assert;
+
+/**
+ * AssertJ based JSON tester backed by Jsonb. Usually instantiated via
+ * {@link #initFields(Object, Jsonb)}, for example: <pre class="code">
+ * public class ExampleObjectJsonTests {
+ *
+ * 	private JsonbTester&lt;ExampleObject&gt; json;
+ *
+ * 	&#064;Before
+ * 	public void setup() {
+ * 		Jsonb jsonb = JsonbBuilder.create();
+ * 		JsonbTester.initFields(this, jsonb);
+ * 	}
+ *
+ * 	&#064;Test
+ * 	public void testWriteJson() throws IOException {
+ * 		ExampleObject object = // ...
+ * 		assertThat(json.write(object)).isEqualToJson(&quot;expected.json&quot;);
+ * 	}
+ *
+ * }
+ * </pre>
+ *
+ * See {@link AbstractJsonMarshalTester} for more details.
+ *
+ * @param <T> the type under test
+ * @author Eddú Meléndez
+ * @since 2.0.0
+ */
+public class JsonbTester<T> extends AbstractJsonMarshalTester<T> {
+
+	private final Jsonb jsonb;
+
+	/**
+	 * Create a new uninitialized {@link JsonbTester} instance.
+	 * @param jsonb the Jsonb instance
+	 */
+	protected JsonbTester(Jsonb jsonb) {
+		Assert.notNull(jsonb, "Jsonb must not be null");
+		this.jsonb = jsonb;
+	}
+
+	/**
+	 * Create a new {@link JsonbTester} instance.
+	 * @param resourceLoadClass the source class used to load resources
+	 * @param type the type under test
+	 * @param jsonb the Jsonb instance
+	 * @see #initFields(Object, Jsonb)
+	 */
+	public JsonbTester(Class<?> resourceLoadClass, ResolvableType type, Jsonb jsonb) {
+		super(resourceLoadClass, type);
+		Assert.notNull(jsonb, "Jsonb must not be null");
+		this.jsonb = jsonb;
+	}
+
+	@Override
+	protected String writeObject(T value, ResolvableType type) throws IOException {
+		return this.jsonb.toJson(value, type.getType());
+	}
+
+	@Override
+	protected T readObject(Reader reader, ResolvableType type) throws IOException {
+		return this.jsonb.fromJson(reader, type.getType());
+	}
+
+	/**
+	 * Utility method to initialize {@link JsonbTester} fields. See {@link JsonbTester
+	 * class-level documentation} for example usage.
+	 * @param testInstance the test instance
+	 * @param jsonb the Jsonb instance
+	 */
+	public static void initFields(Object testInstance, Jsonb jsonb) {
+		new JsonbFieldInitializer().initFields(testInstance, jsonb);
+	}
+
+	/**
+	 * Utility method to initialize {@link JsonbTester} fields. See {@link JsonbTester
+	 * class-level documentation} for example usage.
+	 * @param testInstance the test instance
+	 * @param jsonb an object factory to create the Jsonb instance
+	 */
+	public static void initFields(Object testInstance, ObjectFactory<Jsonb> jsonb) {
+		new JsonbTester.JsonbFieldInitializer().initFields(testInstance, jsonb);
+	}
+
+	/**
+	 * {@link FieldInitializer} for Jsonb.
+	 */
+	private static class JsonbFieldInitializer extends FieldInitializer<Jsonb> {
+
+		protected JsonbFieldInitializer() {
+			super(JsonbTester.class);
+		}
+
+		@Override
+		protected AbstractJsonMarshalTester<Object> createTester(
+				Class<?> resourceLoadClass, ResolvableType type, Jsonb marshaller) {
+			return new JsonbTester<>(resourceLoadClass, type, marshaller);
+		}
+	}
+
+}

spring-boot-test/src/test/java/org/springframework/boot/test/json/JsonbTesterTests.java

@@ -0,0 +1,89 @@
+/*
+ * Copyright 2012-2017 the original author or authors.
+ *
+ * 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.
+ */
+
+package org.springframework.boot.test.json;
+
+import java.util.List;
+
+import javax.json.bind.Jsonb;
+import javax.json.bind.JsonbBuilder;
+
+import org.junit.Test;
+
+import org.springframework.core.ResolvableType;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link JsonbTester}.
+ *
+ * @author Eddú Meléndez
+ */
+public class JsonbTesterTests extends AbstractJsonMarshalTesterTests {
+
+	@Test
+	public void initFieldsWhenTestIsNullShouldThrowException() {
+		this.thrown.expect(IllegalArgumentException.class);
+		this.thrown.expectMessage("TestInstance must not be null");
+		JsonbTester.initFields(null, JsonbBuilder.create());
+	}
+
+	@Test
+	public void initFieldsWhenMarshallerIsNullShouldThrowException() {
+		this.thrown.expect(IllegalArgumentException.class);
+		this.thrown.expectMessage("Marshaller must not be null");
+		JsonbTester.initFields(new InitFieldsTestClass(), (Jsonb) null);
+	}
+
+	@Test
+	public void initFieldsShouldSetNullFields() {
+		InitFieldsTestClass test = new InitFieldsTestClass();
+		assertThat(test.test).isNull();
+		assertThat(test.base).isNull();
+		JsonbTester.initFields(test, JsonbBuilder.create());
+		assertThat(test.test).isNotNull();
+		assertThat(test.base).isNotNull();
+		assertThat(test.test.getType().resolve()).isEqualTo(List.class);
+		assertThat(test.test.getType().resolveGeneric()).isEqualTo(ExampleObject.class);
+	}
+
+	@Override
+	protected AbstractJsonMarshalTester<Object> createTester(Class<?> resourceLoadClass,
+			ResolvableType type) {
+		return new JsonbTester<>(resourceLoadClass, type, JsonbBuilder.create());
+	}
+
+	static abstract class InitFieldsBaseClass {
+
+		public JsonbTester<ExampleObject> base;
+
+		public JsonbTester<ExampleObject> baseSet = new JsonbTester<>(
+				InitFieldsBaseClass.class, ResolvableType.forClass(ExampleObject.class),
+				JsonbBuilder.create());
+
+	}
+
+	static class InitFieldsTestClass extends InitFieldsBaseClass {
+
+		public JsonbTester<List<ExampleObject>> test;
+
+		public JsonbTester<ExampleObject> testSet = new JsonbTester<>(
+				InitFieldsBaseClass.class, ResolvableType.forClass(ExampleObject.class),
+				JsonbBuilder.create());
+
+	}
+
+}