1 // ========================================================================
2 // Copyright (c) 1996-2009 Mort Bay Consulting Pty. Ltd.
3 // ------------------------------------------------------------------------
4 // All rights reserved. This program and the accompanying materials
5 // are made available under the terms of the Eclipse Public License v1.0
6 // and Apache License v2.0 which accompanies this distribution.
7 // The Eclipse Public License is available at
8 // http://www.eclipse.org/legal/epl-v10.html
9 // The Apache License v2.0 is available at
10 // http://www.opensource.org/licenses/apache2.0.php
11 // You may elect to redistribute this code under either of these licenses.
12 // ========================================================================
13
14 package org.eclipse.jetty.servlet;
15
16 import java.util.Collections;
17 import java.util.Enumeration;
18 import java.util.HashMap;
19 import java.util.Map;
20
21 import javax.servlet.ServletContext;
22 import javax.servlet.UnavailableException;
23
24 import org.eclipse.jetty.server.handler.ContextHandler;
25 import org.eclipse.jetty.util.Loader;
26 import org.eclipse.jetty.util.component.AbstractLifeCycle;
27 import org.eclipse.jetty.util.log.Log;
28
29
30 /* --------------------------------------------------------------------- */
31 /**
32 *
33 */
34 public class Holder extends AbstractLifeCycle
35 {
36 protected transient Class<?> _class;
37 protected String _className;
38 protected String _displayName;
39 protected Map _initParams;
40 protected boolean _extInstance;
41 protected boolean _asyncSupported=true;
42
43 /* ---------------------------------------------------------------- */
44 protected String _name;
45 protected ServletHandler _servletHandler;
46
47 protected Holder()
48 {}
49
50 /* ---------------------------------------------------------------- */
51 protected Holder(Class held)
52 {
53 _class=held;
54 if (held!=null)
55 {
56 _className=held.getName();
57 _name=held.getName()+"-"+this.hashCode();
58 }
59 }
60
61 /* ------------------------------------------------------------ */
62 public void doStart()
63 throws Exception
64 {
65 //if no class already loaded and no classname, make servlet permanently unavailable
66 if (_class==null && (_className==null || _className.equals("")))
67 throw new UnavailableException("No class for Servlet or Filter", -1);
68
69 //try to load class
70 if (_class==null)
71 {
72 try
73 {
74 _class=Loader.loadClass(Holder.class, _className);
75 if(Log.isDebugEnabled())Log.debug("Holding {}",_class);
76 }
77 catch (Exception e)
78 {
79 Log.warn(e);
80 throw new UnavailableException(e.getMessage(), -1);
81 }
82 }
83 }
84
85 /* ------------------------------------------------------------ */
86 public void doStop()
87 throws Exception
88 {
89 if (!_extInstance)
90 _class=null;
91 }
92
93 /* ------------------------------------------------------------ */
94 public String getClassName()
95 {
96 return _className;
97 }
98
99 /* ------------------------------------------------------------ */
100 public Class getHeldClass()
101 {
102 return _class;
103 }
104
105 /* ------------------------------------------------------------ */
106 public String getDisplayName()
107 {
108 return _displayName;
109 }
110
111 /* ---------------------------------------------------------------- */
112 public String getInitParameter(String param)
113 {
114 if (_initParams==null)
115 return null;
116 return (String)_initParams.get(param);
117 }
118
119 /* ------------------------------------------------------------ */
120 public Enumeration getInitParameterNames()
121 {
122 if (_initParams==null)
123 return Collections.enumeration(Collections.EMPTY_LIST);
124 return Collections.enumeration(_initParams.keySet());
125 }
126
127 /* ---------------------------------------------------------------- */
128 public Map getInitParameters()
129 {
130 return _initParams;
131 }
132
133 /* ------------------------------------------------------------ */
134 public String getName()
135 {
136 return _name;
137 }
138
139 /* ------------------------------------------------------------ */
140 /**
141 * @return Returns the servletHandler.
142 */
143 public ServletHandler getServletHandler()
144 {
145 return _servletHandler;
146 }
147
148 /* ------------------------------------------------------------ */
149 public synchronized Object newInstance()
150 throws InstantiationException,
151 IllegalAccessException
152 {
153 if (_class==null)
154 throw new InstantiationException("!"+_className);
155 return _class.newInstance();
156 }
157
158 /* ------------------------------------------------------------ */
159 public void destroyInstance(Object instance)
160 throws Exception
161 {
162 }
163
164 /* ------------------------------------------------------------ */
165 /**
166 * @param className The className to set.
167 */
168 public void setClassName(String className)
169 {
170 _className = className;
171 _class=null;
172 }
173
174 /* ------------------------------------------------------------ */
175 /**
176 * @param held The class to hold
177 */
178 public void setHeldClass(Class held)
179 {
180 _class=held;
181 _className = held!=null?held.getName():null;
182 }
183
184 /* ------------------------------------------------------------ */
185 public void setDisplayName(String name)
186 {
187 _displayName=name;
188 }
189
190 /* ------------------------------------------------------------ */
191 public void setInitParameter(String param,String value)
192 {
193 if (_initParams==null)
194 _initParams=new HashMap(3);
195 _initParams.put(param,value);
196 }
197
198 /* ---------------------------------------------------------------- */
199 public void setInitParameters(Map map)
200 {
201 _initParams=map;
202 }
203
204 /* ------------------------------------------------------------ */
205 /**
206 * The name is a primary key for the held object.
207 * Ensure that the name is set BEFORE adding a Holder
208 * (eg ServletHolder or FilterHolder) to a ServletHandler.
209 * @param name The name to set.
210 */
211 public void setName(String name)
212 {
213 _name = name;
214 }
215
216 /* ------------------------------------------------------------ */
217 /**
218 * @param servletHandler The {@link ServletHandler} that will handle requests dispatched to this servlet.
219 */
220 public void setServletHandler(ServletHandler servletHandler)
221 {
222 _servletHandler = servletHandler;
223 }
224
225 /* ------------------------------------------------------------ */
226 public void setAsyncSupported(boolean suspendable)
227 {
228 _asyncSupported=suspendable;
229 }
230
231 /* ------------------------------------------------------------ */
232 public boolean isAsyncSupported()
233 {
234 return _asyncSupported;
235 }
236
237 /* ------------------------------------------------------------ */
238 public String toString()
239 {
240 return _name;
241 }
242
243 /* ------------------------------------------------------------ */
244 protected void illegalStateIfContextStarted()
245 {
246 if (_servletHandler!=null)
247 {
248 ContextHandler.Context context=(ContextHandler.Context)_servletHandler.getServletContext();
249 if (context!=null && context.getContextHandler().isStarted())
250 throw new IllegalStateException("Started");
251 }
252 }
253
254 /* ------------------------------------------------------------ */
255 /* ------------------------------------------------------------ */
256 /* ------------------------------------------------------------ */
257 protected class HolderConfig
258 {
259
260 /* -------------------------------------------------------- */
261 public ServletContext getServletContext()
262 {
263 return _servletHandler.getServletContext();
264 }
265
266 /* -------------------------------------------------------- */
267 public String getInitParameter(String param)
268 {
269 return Holder.this.getInitParameter(param);
270 }
271
272 /* -------------------------------------------------------- */
273 public Enumeration getInitParameterNames()
274 {
275 return Holder.this.getInitParameterNames();
276 }
277 }
278 }
279
280
281
282
283