1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
|
//
// ========================================================================
// Copyright (c) 1995-2016 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
//
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
//
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
//
// You may elect to redistribute this code under either of these licenses.
// ========================================================================
//
package org.eclipse.jetty.server.handler;
import java.io.IOException;
import java.util.Arrays;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.eclipse.jetty.server.Handler;
import org.eclipse.jetty.server.HandlerContainer;
import org.eclipse.jetty.server.Request;
import org.eclipse.jetty.util.annotation.ManagedAttribute;
import org.eclipse.jetty.util.annotation.ManagedObject;
import org.eclipse.jetty.util.component.LifeCycle;
/* ------------------------------------------------------------ */
/** A <code>HandlerWrapper</code> acts as a {@link Handler} but delegates the {@link Handler#handle handle} method and
* {@link LifeCycle life cycle} events to a delegate. This is primarily used to implement the <i>Decorator</i> pattern.
*
*/
@ManagedObject("Handler wrapping another Handler")
public class HandlerWrapper extends AbstractHandlerContainer
{
protected Handler _handler;
/* ------------------------------------------------------------ */
/**
*
*/
public HandlerWrapper()
{
}
/* ------------------------------------------------------------ */
/**
* @return Returns the handlers.
*/
@ManagedAttribute(value="Wrapped Handler", readonly=true)
public Handler getHandler()
{
return _handler;
}
/* ------------------------------------------------------------ */
/**
* @return Returns the handlers.
*/
@Override
public Handler[] getHandlers()
{
if (_handler==null)
return new Handler[0];
return new Handler[] {_handler};
}
/* ------------------------------------------------------------ */
/**
* @param handler Set the {@link Handler} which should be wrapped.
*/
public void setHandler(Handler handler)
{
if (isStarted())
throw new IllegalStateException(STARTED);
// check for loops
if (handler==this || (handler instanceof HandlerContainer &&
Arrays.asList(((HandlerContainer)handler).getChildHandlers()).contains(this)))
throw new IllegalStateException("setHandler loop");
if (handler!=null)
handler.setServer(getServer());
Handler old=_handler;
_handler=handler;
updateBean(old,_handler,true);
}
/* ------------------------------------------------------------ */
/**
* Replace the current handler with another HandlerWrapper
* linked to the current handler.
* <p>
* This is equivalent to:
* <pre>
* wrapper.setHandler(getHandler());
* setHandler(wrapper);
* </pre>
* @param wrapper the wrapper to insert
*/
public void insertHandler(HandlerWrapper wrapper)
{
if (wrapper==null)
throw new IllegalArgumentException();
HandlerWrapper tail = wrapper;
while(tail.getHandler() instanceof HandlerWrapper)
tail=(HandlerWrapper)tail.getHandler();
if (tail.getHandler()!=null)
throw new IllegalArgumentException("bad tail of inserted wrapper chain");
Handler next=getHandler();
setHandler(wrapper);
tail.setHandler(next);
}
/* ------------------------------------------------------------ */
@Override
public void handle(String target, Request baseRequest, HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException
{
Handler handler=_handler;
if (handler!=null)
handler.handle(target,baseRequest, request, response);
}
/* ------------------------------------------------------------ */
@Override
protected void expandChildren(List<Handler> list, Class<?> byClass)
{
expandHandler(_handler,list,byClass);
}
/* ------------------------------------------------------------ */
@Override
public void destroy()
{
if (!isStopped())
throw new IllegalStateException("!STOPPED");
Handler child=getHandler();
if (child!=null)
{
setHandler(null);
child.destroy();
}
super.destroy();
}
}
|
