001 /**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018
019 package org.apache.hadoop.lib.wsrs;
020
021 import org.apache.hadoop.classification.InterfaceAudience;
022 import org.json.simple.JSONObject;
023
024 import javax.ws.rs.Produces;
025 import javax.ws.rs.WebApplicationException;
026 import javax.ws.rs.core.MediaType;
027 import javax.ws.rs.core.MultivaluedMap;
028 import javax.ws.rs.ext.MessageBodyWriter;
029 import javax.ws.rs.ext.Provider;
030 import java.io.IOException;
031 import java.io.OutputStream;
032 import java.io.OutputStreamWriter;
033 import java.io.Writer;
034 import java.lang.annotation.Annotation;
035 import java.lang.reflect.Type;
036 import java.util.Map;
037
038 @Provider
039 @Produces(MediaType.APPLICATION_JSON)
040 @InterfaceAudience.Private
041 public class JSONMapProvider implements MessageBodyWriter<Map> {
042 private static final String ENTER = System.getProperty("line.separator");
043
044 @Override
045 public boolean isWriteable(Class<?> aClass, Type type, Annotation[] annotations, MediaType mediaType) {
046 return Map.class.isAssignableFrom(aClass);
047 }
048
049 @Override
050 public long getSize(Map map, Class<?> aClass, Type type, Annotation[] annotations, MediaType mediaType) {
051 return -1;
052 }
053
054 @Override
055 public void writeTo(Map map, Class<?> aClass, Type type, Annotation[] annotations,
056 MediaType mediaType, MultivaluedMap<String, Object> stringObjectMultivaluedMap,
057 OutputStream outputStream) throws IOException, WebApplicationException {
058 Writer writer = new OutputStreamWriter(outputStream);
059 JSONObject.writeJSONString(map, writer);
060 writer.write(ENTER);
061 writer.flush();
062 }
063
064 }