001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.juneau.rest.processor;
018
019import java.io.*;
020
021import org.apache.juneau.http.header.*;
022import org.apache.juneau.rest.*;
023
024/**
025 * Response handler for {@link Throwable} objects.
026 *
027 * <p>
028 * Adds a <c>Thrown</c> header to the response and returns <c>0</c> so that the processor chain can continue.
029 *
030 * <h5 class='section'>See Also:</h5><ul>
031 *    <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/ResponseProcessors">Response Processors</a>
032 * </ul>
033 */
034public class ThrowableProcessor implements ResponseProcessor {
035
036   @Override /* ResponseProcessor */
037   public int process(RestOpSession opSession) throws IOException {
038
039      RestResponse res = opSession.getResponse();
040      Throwable t = res.getContent(Throwable.class);
041
042      if (t == null)
043         return NEXT;
044
045      res.addHeader(Thrown.of(t));
046
047      return NEXT; // Continue processing as bean.
048   }
049}
050