1 //
2 // ========================================================================
3 // Copyright (c) 1995-2013 Mort Bay Consulting Pty. Ltd.
4 // ------------------------------------------------------------------------
5 // All rights reserved. This program and the accompanying materials
6 // are made available under the terms of the Eclipse Public License v1.0
7 // and Apache License v2.0 which accompanies this distribution.
8 //
9 // The Eclipse Public License is available at
10 // http://www.eclipse.org/legal/epl-v10.html
11 //
12 // The Apache License v2.0 is available at
13 // http://www.opensource.org/licenses/apache2.0.php
14 //
15 // You may elect to redistribute this code under either of these licenses.
16 // ========================================================================
17 //
18
19 package org.eclipse.jetty.server.handler;
20
21 import java.io.IOException;
22 import java.util.concurrent.CountDownLatch;
23
24 import javax.servlet.ServletException;
25 import javax.servlet.http.HttpServletRequest;
26 import javax.servlet.http.HttpServletResponse;
27
28 import org.eclipse.jetty.server.Handler;
29 import org.eclipse.jetty.server.Request;
30 import org.eclipse.jetty.server.Server;
31 import org.eclipse.jetty.util.LazyList;
32 import org.eclipse.jetty.util.MultiException;
33
34 /* ------------------------------------------------------------ */
35 /** A collection of handlers.
36 * <p>
37 * The default implementations calls all handlers in list order,
38 * regardless of the response status or exceptions. Derived implementation
39 * may alter the order or the conditions of calling the contained
40 * handlers.
41 * <p>
42 *
43 * @org.apache.xbean.XBean
44 */
45 public class HandlerCollection extends AbstractHandlerContainer
46 {
47 private final boolean _mutableWhenRunning;
48 private volatile Handler[] _handlers;
49 private boolean _parallelStart=false;
50
51 /* ------------------------------------------------------------ */
52 public HandlerCollection()
53 {
54 _mutableWhenRunning=false;
55 }
56
57 /* ------------------------------------------------------------ */
58 public HandlerCollection(boolean mutableWhenRunning)
59 {
60 _mutableWhenRunning=mutableWhenRunning;
61 }
62
63 /* ------------------------------------------------------------ */
64 /**
65 * @return Returns the handlers.
66 */
67 public Handler[] getHandlers()
68 {
69 return _handlers;
70 }
71
72 /* ------------------------------------------------------------ */
73 /**
74 *
75 * @param handlers The handlers to set.
76 */
77 public void setHandlers(Handler[] handlers)
78 {
79 if (!_mutableWhenRunning && isStarted())
80 throw new IllegalStateException(STARTED);
81
82 Handler [] old_handlers = _handlers==null?null:_handlers.clone();
83 _handlers = handlers;
84
85 Server server = getServer();
86 MultiException mex = new MultiException();
87 for (int i=0;handlers!=null && i<handlers.length;i++)
88 {
89 if (handlers[i].getServer()!=server)
90 handlers[i].setServer(server);
91 }
92
93 if (getServer()!=null)
94 getServer().getContainer().update(this, old_handlers, handlers, "handler");
95
96 // stop old handlers
97 for (int i=0;old_handlers!=null && i<old_handlers.length;i++)
98 {
99 if (old_handlers[i]!=null)
100 {
101 try
102 {
103 if (old_handlers[i].isStarted())
104 old_handlers[i].stop();
105 }
106 catch (Throwable e)
107 {
108 mex.add(e);
109 }
110 }
111 }
112
113 mex.ifExceptionThrowRuntime();
114 }
115
116
117
118 /* ------------------------------------------------------------ */
119 /** Get the parrallelStart.
120 * @return true if the contained handlers are started in parallel.
121 */
122 public boolean isParallelStart()
123 {
124 return _parallelStart;
125 }
126
127
128
129 /* ------------------------------------------------------------ */
130 /** Set the parallelStart.
131 * @param parallelStart If true, contained handlers are started in parallel.
132 */
133 public void setParallelStart(boolean parallelStart)
134 {
135 this._parallelStart = parallelStart;
136 }
137
138
139 /* ------------------------------------------------------------ */
140 /**
141 * @see Handler#handle(String, Request, HttpServletRequest, HttpServletResponse)
142 */
143 public void handle(String target, Request baseRequest, HttpServletRequest request, HttpServletResponse response)
144 throws IOException, ServletException
145 {
146 if (_handlers!=null && isStarted())
147 {
148 MultiException mex=null;
149
150 for (int i=0;i<_handlers.length;i++)
151 {
152 try
153 {
154 _handlers[i].handle(target,baseRequest, request, response);
155 }
156 catch(IOException e)
157 {
158 throw e;
159 }
160 catch(RuntimeException e)
161 {
162 throw e;
163 }
164 catch(Exception e)
165 {
166 if (mex==null)
167 mex=new MultiException();
168 mex.add(e);
169 }
170 }
171 if (mex!=null)
172 {
173 if (mex.size()==1)
174 throw new ServletException(mex.getThrowable(0));
175 else
176 throw new ServletException(mex);
177 }
178
179 }
180 }
181
182 /* ------------------------------------------------------------ */
183 /*
184 * @see org.eclipse.jetty.server.server.handler.AbstractHandler#doStart()
185 */
186 @Override
187 protected void doStart() throws Exception
188 {
189 final MultiException mex=new MultiException();
190 if (_handlers!=null)
191 {
192 if (_parallelStart)
193 {
194 final CountDownLatch latch = new CountDownLatch(_handlers.length);
195 final ClassLoader loader = Thread.currentThread().getContextClassLoader();
196 for (int i=0;i<_handlers.length;i++)
197 {
198 final int h=i;
199 getServer().getThreadPool().dispatch(
200 new Runnable()
201 {
202 public void run()
203 {
204 ClassLoader orig = Thread.currentThread().getContextClassLoader();
205 try
206 {
207 Thread.currentThread().setContextClassLoader(loader);
208 _handlers[h].start();
209 }
210 catch(Throwable e)
211 {
212 mex.add(e);
213 }
214 finally
215 {
216 Thread.currentThread().setContextClassLoader(orig);
217 latch.countDown();
218 }
219 }
220 }
221 );
222 }
223 latch.await();
224 }
225 else
226 {
227 for (int i=0;i<_handlers.length;i++)
228 {
229 try{_handlers[i].start();}
230 catch(Throwable e){mex.add(e);}
231 }
232 }
233 }
234 super.doStart();
235 mex.ifExceptionThrow();
236 }
237
238 /* ------------------------------------------------------------ */
239 /*
240 * @see org.eclipse.jetty.server.server.handler.AbstractHandler#doStop()
241 */
242 @Override
243 protected void doStop() throws Exception
244 {
245 MultiException mex=new MultiException();
246 try { super.doStop(); } catch(Throwable e){mex.add(e);}
247 if (_handlers!=null)
248 {
249 for (int i=_handlers.length;i-->0;)
250 try{_handlers[i].stop();}catch(Throwable e){mex.add(e);}
251 }
252 mex.ifExceptionThrow();
253 }
254
255 /* ------------------------------------------------------------ */
256 @Override
257 public void setServer(Server server)
258 {
259 if (isStarted())
260 throw new IllegalStateException(STARTED);
261
262 Server old_server=getServer();
263
264 super.setServer(server);
265
266 Handler[] h=getHandlers();
267 for (int i=0;h!=null && i<h.length;i++)
268 h[i].setServer(server);
269
270 if (server!=null && server!=old_server)
271 server.getContainer().update(this, null,_handlers, "handler");
272
273 }
274
275 /* ------------------------------------------------------------ */
276 /* Add a handler.
277 * This implementation adds the passed handler to the end of the existing collection of handlers.
278 * @see org.eclipse.jetty.server.server.HandlerContainer#addHandler(org.eclipse.jetty.server.server.Handler)
279 */
280 public void addHandler(Handler handler)
281 {
282 setHandlers((Handler[])LazyList.addToArray(getHandlers(), handler, Handler.class));
283 }
284
285 /* ------------------------------------------------------------ */
286 public void removeHandler(Handler handler)
287 {
288 Handler[] handlers = getHandlers();
289
290 if (handlers!=null && handlers.length>0 )
291 setHandlers((Handler[])LazyList.removeFromArray(handlers, handler));
292 }
293
294 /* ------------------------------------------------------------ */
295 @Override
296 protected Object expandChildren(Object list, Class byClass)
297 {
298 Handler[] handlers = getHandlers();
299 for (int i=0;handlers!=null && i<handlers.length;i++)
300 list=expandHandler(handlers[i], list, byClass);
301 return list;
302 }
303
304 /* ------------------------------------------------------------ */
305 @Override
306 public void destroy()
307 {
308 if (!isStopped())
309 throw new IllegalStateException("!STOPPED");
310 Handler[] children=getChildHandlers();
311 setHandlers(null);
312 for (Handler child: children)
313 child.destroy();
314 super.destroy();
315 }
316 }