1 /*
2 * $HeadURL: https://svn.apache.org/repos/asf/httpcomponents/oac.hc3x/trunk/src/test/org/apache/commons/httpclient/server/HttpRequestHandlerChain.java $
3 * $Revision$
4 * $Date$
5 *
6 * ====================================================================
7 *
8 * Licensed to the Apache Software Foundation (ASF) under one or more
9 * contributor license agreements. See the NOTICE file distributed with
10 * this work for additional information regarding copyright ownership.
11 * The ASF licenses this file to You under the Apache License, Version 2.0
12 * (the "License"); you may not use this file except in compliance with
13 * the License. You may obtain a copy of the License at
14 *
15 * http://www.apache.org/licenses/LICENSE-2.0
16 *
17 * Unless required by applicable law or agreed to in writing, software
18 * distributed under the License is distributed on an "AS IS" BASIS,
19 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
20 * See the License for the specific language governing permissions and
21 * limitations under the License.
22 * ====================================================================
23 *
24 * This software consists of voluntary contributions made by many
25 * individuals on behalf of the Apache Software Foundation. For more
26 * information on the Apache Software Foundation, please see
27 * <http://www.apache.org/>.
28 *
29 * [Additional notices, if required by prior licensing conditions]
30 *
31 */
32
33 package org.apache.commons.httpclient.server;
34
35 import java.io.IOException;
36 import java.util.ArrayList;
37 import java.util.Iterator;
38 import java.util.List;
39
40 /***
41 * Maintains a chain of {@link HttpRequestHandler}s where new request-handlers
42 * can be prepended/appended.
43 *
44 * For each call to {@link #processRequest(ResponseWriter,SimpleHttpServerConnection,RequestLine,Header[])}
45 * we iterate over the chain from the start to the end, stopping as soon as a handler
46 * has claimed the output.
47 *
48 * @author Christian Kohlschuetter
49 */
50 public class HttpRequestHandlerChain implements HttpRequestHandler {
51
52 private List subhandlers = new ArrayList();
53
54 public HttpRequestHandlerChain(final HttpRequestHandlerChain chain) {
55 super();
56 if (chain != null) {
57 this.subhandlers.clear();
58 this.subhandlers.addAll(chain.subhandlers);
59 }
60 }
61
62 public HttpRequestHandlerChain() {
63 super();
64 }
65
66 public synchronized void clear() {
67 subhandlers.clear();
68 }
69
70 public synchronized void prependHandler(HttpRequestHandler handler) {
71 subhandlers.add(0,handler);
72 }
73
74 public synchronized void appendHandler(HttpRequestHandler handler) {
75 subhandlers.add(handler);
76 }
77
78 public synchronized boolean processRequest(
79 final SimpleHttpServerConnection conn,
80 final SimpleRequest request) throws IOException
81 {
82 for(Iterator it=subhandlers.iterator();it.hasNext();) {
83 HttpRequestHandler h = (HttpRequestHandler)it.next();
84 boolean stop = h.processRequest(conn, request);
85 if (stop) {
86 return true;
87 }
88 }
89 return false;
90 }
91 }