/*

  * Licensed to the Apache Software Foundation (ASF) under one

  * or more contributor license agreements. See the NOTICE file

  * distributed with this work for additional information

  * regarding copyright ownership. The ASF licenses this file

  * to you 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.apache.johnzon.jaxrs;

 import javax.json.Json;

 import javax.json.JsonStructure;

 import javax.json.JsonWriter;

 import javax.json.JsonWriterFactory;

 import javax.ws.rs.Produces;

 import javax.ws.rs.WebApplicationException;

 import javax.ws.rs.core.MediaType;

 import javax.ws.rs.core.MultivaluedMap;

 import javax.ws.rs.ext.MessageBodyWriter;

 import javax.ws.rs.ext.Provider;

 import java.io.Flushable;

 import java.io.IOException;

 import java.io.OutputStream;

 import java.lang.annotation.Annotation;

 import java.lang.reflect.Type;

 import java.util.Collections;

 import static javax.ws.rs.core.MediaType.WILDCARD;

 @Provider

 @Produces(WILDCARD)

 public class JsrMessageBodyWriter implements MessageBodyWriter<JsonStructure> {

     private final JsonWriterFactory factory;

     private final boolean close;

     public JsrMessageBodyWriter() {

         this(Json.createWriterFactory(Collections.<String, Object>emptyMap()), false);

     }

     public JsrMessageBodyWriter(final JsonWriterFactory factory, final boolean closeStreams) {

         this.factory = factory;

         this.close = closeStreams;

     }

     @Override

     public boolean isWriteable(final Class<?> aClass, final Type type,

                                final Annotation[] annotations, final MediaType mediaType) {

         return JsonStructure.class.isAssignableFrom(aClass);

     }

     @Override

     public long getSize(final JsonStructure jsonStructure, final Class<?> aClass,

                         final Type type, final Annotation[] annotations,

                         final MediaType mediaType) {

         return -1;

     }

     @Override

     public void writeTo(final JsonStructure jsonStructure,

                         final Class<?> aClass, final Type type,

                         final Annotation[] annotations, final MediaType mediaType,

                         final MultivaluedMap<String, Object> stringObjectMultivaluedMap,

                         final OutputStream outputStream) throws IOException, WebApplicationException {

         JsonWriter writer = null;

         try {

             writer = factory.createWriter(outputStream);

             writer.write(jsonStructure);

         } finally {

             if (writer != null) {

                 if (close) {

                     writer.close();

                 } else if (Flushable.class.isInstance(writer)) {

                     Flushable.class.cast(writer).flush();

                 }

             }

         }

     }

 }