InstanceEvent


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3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    * 
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   * 
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  
19  package org.apache.catalina;
20  
21  
22  import java.util.EventObject  ;
23  import javax.servlet.Filter  ;
24  import javax.servlet.Servlet  ;
25  import javax.servlet.ServletRequest  ;
26  import javax.servlet.ServletResponse  ;
27  
28  
29  /**
30   * General event for notifying listeners of significant events related to
31   * a specific instance of a Servlet, or a specific instance of a Filter,
32   * as opposed to the Wrapper component that manages it.
33   *
34   * @author Craig R. McClanahan
35   * @version $Revision: 467222 $ $Date: 2006-10-24 05:17:11 +0200 (mar., 24 oct. 2006) $
36   */
37  
38  public final class InstanceEvent
39      extends EventObject   {
40  
41  
42      // ----------------------------------------------------- Manifest Constants
43  
44  
45      /**
46       * The event indicating that the <code>init()</code> method is about
47       * to be called for this instance.
48       */
49      public static final String   BEFORE_INIT_EVENT = "beforeInit";
50  
51  
52      /**
53       * The event indicating that the <code>init()</code> method has returned.
54       */
55      public static final String   AFTER_INIT_EVENT = "afterInit";
56  
57  
58      /**
59       * The event indicating that the <code>service()</code> method is about
60       * to be called on a servlet.  The <code>servlet</code> property contains
61       * the servlet being called, and the <code>request</code> and
62       * <code>response</code> properties contain the current request and
63       * response being processed.
64       */
65      public static final String   BEFORE_SERVICE_EVENT = "beforeService";
66  
67  
68      /**
69       * The event indicating that the <code>service()</code> method has
70       * returned.  The <code>servlet</code> property contains the servlet
71       * that was called, and the <code>request</code> and
72       * <code>response</code> properties contain the current request and
73       * response being processed.
74       */
75      public static final String   AFTER_SERVICE_EVENT = "afterService";
76  
77  
78      /**
79       * The event indicating that the <code>destroy</code> method is about
80       * to be called for this instance.
81       */
82      public static final String   BEFORE_DESTROY_EVENT = "beforeDestroy";
83  
84  
85      /**
86       * The event indicating that the <code>destroy()</code> method has
87       * returned.
88       */
89      public static final String   AFTER_DESTROY_EVENT = "afterDestroy";
90  
91  
92      /**
93       * The event indicating that the <code>service()</code> method of a
94       * servlet accessed via a request dispatcher is about to be called.
95       * The <code>servlet</code> property contains a reference to the
96       * dispatched-to servlet instance, and the <code>request</code> and
97       * <code>response</code> properties contain the current request and
98       * response being processed.  The <code>wrapper</code> property will
99       * contain a reference to the dispatched-to Wrapper.
100      */
101     public static final String   BEFORE_DISPATCH_EVENT = "beforeDispatch";
102 
103 
104     /**
105      * The event indicating that the <code>service()</code> method of a
106      * servlet accessed via a request dispatcher has returned.  The
107      * <code>servlet</code> property contains a reference to the
108      * dispatched-to servlet instance, and the <code>request</code> and
109      * <code>response</code> properties contain the current request and
110      * response being processed.  The <code>wrapper</code> property will
111      * contain a reference to the dispatched-to Wrapper.
112      */
113     public static final String   AFTER_DISPATCH_EVENT = "afterDispatch";
114 
115 
116     /**
117      * The event indicating that the <code>doFilter()</code> method of a
118      * Filter is about to be called.  The <code>filter</code> property
119      * contains a reference to the relevant filter instance, and the
120      * <code>request</code> and <code>response</code> properties contain
121      * the current request and response being processed.
122      */
123     public static final String   BEFORE_FILTER_EVENT = "beforeFilter";
124 
125 
126     /**
127      * The event indicating that the <code>doFilter()</code> method of a
128      * Filter has returned.  The <code>filter</code> property contains
129      * a reference to the relevant filter instance, and the
130      * <code>request</code> and <code>response</code> properties contain
131      * the current request and response being processed.
132      */
133     public static final String   AFTER_FILTER_EVENT = "afterFilter";
134 
135 
136     // ----------------------------------------------------------- Constructors
137 
138 
139     /**
140      * Construct a new InstanceEvent with the specified parameters.  This
141      * constructor is used for filter lifecycle events.
142      *
143      * @param wrapper Wrapper managing this servlet instance
144      * @param filter Filter instance for which this event occurred
145      * @param type Event type (required)
146      */
147     public InstanceEvent(Wrapper wrapper, Filter   filter, String   type) {
148 
149       super(wrapper);
150       this.wrapper = wrapper;
151       this.filter = filter;
152       this.servlet = null;
153       this.type = type;
154 
155     }
156 
157 
158     /**
159      * Construct a new InstanceEvent with the specified parameters.  This
160      * constructor is used for filter lifecycle events.
161      *
162      * @param wrapper Wrapper managing this servlet instance
163      * @param filter Filter instance for which this event occurred
164      * @param type Event type (required)
165      * @param exception Exception that occurred
166      */
167     public InstanceEvent(Wrapper wrapper, Filter   filter, String   type,
168                          Throwable   exception) {
169 
170       super(wrapper);
171       this.wrapper = wrapper;
172       this.filter = filter;
173       this.servlet = null;
174       this.type = type;
175       this.exception = exception;
176 
177     }
178 
179 
180     /**
181      * Construct a new InstanceEvent with the specified parameters.  This
182      * constructor is used for filter processing events.
183      *
184      * @param wrapper Wrapper managing this servlet instance
185      * @param filter Filter instance for which this event occurred
186      * @param type Event type (required)
187      * @param request Servlet request we are processing
188      * @param response Servlet response we are processing
189      */
190     public InstanceEvent(Wrapper wrapper, Filter   filter, String   type,
191                          ServletRequest   request, ServletResponse   response) {
192 
193       super(wrapper);
194       this.wrapper = wrapper;
195       this.filter = filter;
196       this.servlet = null;
197       this.type = type;
198       this.request = request;
199       this.response = response;
200 
201     }
202 
203 
204     /**
205      * Construct a new InstanceEvent with the specified parameters.  This
206      * constructor is used for filter processing events.
207      *
208      * @param wrapper Wrapper managing this servlet instance
209      * @param filter Filter instance for which this event occurred
210      * @param type Event type (required)
211      * @param request Servlet request we are processing
212      * @param response Servlet response we are processing
213      * @param exception Exception that occurred
214      */
215     public InstanceEvent(Wrapper wrapper, Filter   filter, String   type,
216                          ServletRequest   request, ServletResponse   response,
217                          Throwable   exception) {
218 
219       super(wrapper);
220       this.wrapper = wrapper;
221       this.filter = filter;
222       this.servlet = null;
223       this.type = type;
224       this.request = request;
225       this.response = response;
226       this.exception = exception;
227 
228     }
229 
230 
231     /**
232      * Construct a new InstanceEvent with the specified parameters.  This
233      * constructor is used for processing servlet lifecycle events.
234      *
235      * @param wrapper Wrapper managing this servlet instance
236      * @param servlet Servlet instance for which this event occurred
237      * @param type Event type (required)
238      */
239     public InstanceEvent(Wrapper wrapper, Servlet   servlet, String   type) {
240 
241       super(wrapper);
242       this.wrapper = wrapper;
243       this.filter = null;
244       this.servlet = servlet;
245       this.type = type;
246 
247     }
248 
249 
250     /**
251      * Construct a new InstanceEvent with the specified parameters.  This
252      * constructor is used for processing servlet lifecycle events.
253      *
254      * @param wrapper Wrapper managing this servlet instance
255      * @param servlet Servlet instance for which this event occurred
256      * @param type Event type (required)
257      * @param exception Exception that occurred
258      */
259     public InstanceEvent(Wrapper wrapper, Servlet   servlet, String   type,
260                          Throwable   exception) {
261 
262       super(wrapper);
263       this.wrapper = wrapper;
264       this.filter = null;
265       this.servlet = servlet;
266       this.type = type;
267       this.exception = exception;
268 
269     }
270 
271 
272     /**
273      * Construct a new InstanceEvent with the specified parameters.  This
274      * constructor is used for processing servlet processing events.
275      *
276      * @param wrapper Wrapper managing this servlet instance
277      * @param servlet Servlet instance for which this event occurred
278      * @param type Event type (required)
279      * @param request Servlet request we are processing
280      * @param response Servlet response we are processing
281      */
282     public InstanceEvent(Wrapper wrapper, Servlet   servlet, String   type,
283                          ServletRequest   request, ServletResponse   response) {
284 
285       super(wrapper);
286       this.wrapper = wrapper;
287       this.filter = null;
288       this.servlet = servlet;
289       this.type = type;
290       this.request = request;
291       this.response = response;
292 
293     }
294 
295 
296     /**
297      * Construct a new InstanceEvent with the specified parameters.  This
298      * constructor is used for processing servlet processing events.
299      *
300      * @param wrapper Wrapper managing this servlet instance
301      * @param servlet Servlet instance for which this event occurred
302      * @param type Event type (required)
303      * @param request Servlet request we are processing
304      * @param response Servlet response we are processing
305      * @param exception Exception that occurred
306      */
307     public InstanceEvent(Wrapper wrapper, Servlet   servlet, String   type,
308                          ServletRequest   request, ServletResponse   response,
309                          Throwable   exception) {
310 
311       super(wrapper);
312       this.wrapper = wrapper;
313       this.filter = null;
314       this.servlet = servlet;
315       this.type = type;
316       this.request = request;
317       this.response = response;
318       this.exception = exception;
319 
320     }
321 
322 
323     // ----------------------------------------------------- Instance Variables
324 
325 
326     /**
327      * The exception that was thrown during the processing being reported
328      * by this event (AFTER_INIT_EVENT, AFTER_SERVICE_EVENT, 
329      * AFTER_DESTROY_EVENT, AFTER_DISPATCH_EVENT, and AFTER_FILTER_EVENT only).
330      */
331     private Throwable   exception = null;
332 
333 
334     /**
335      * The Filter instance for which this event occurred (BEFORE_FILTER_EVENT
336      * and AFTER_FILTER_EVENT only).
337      */
338     private Filter   filter = null;
339 
340 
341     /**
342      * The servlet request being processed (BEFORE_FILTER_EVENT,
343      * AFTER_FILTER_EVENT, BEFORE_SERVICE_EVENT, and AFTER_SERVICE_EVENT).
344      */
345     private ServletRequest   request = null;
346 
347 
348     /**
349      * The servlet response being processed (BEFORE_FILTER_EVENT,
350      * AFTER_FILTER_EVENT, BEFORE_SERVICE_EVENT, and AFTER_SERVICE_EVENT).
351      */
352     private ServletResponse   response = null;
353 
354 
355     /**
356      * The Servlet instance for which this event occurred (not present on
357      * BEFORE_FILTER_EVENT or AFTER_FILTER_EVENT events).
358      */
359     private Servlet   servlet = null;
360 
361 
362     /**
363      * The event type this instance represents.
364      */
365     private String   type = null;
366 
367 
368     /**
369      * The Wrapper managing the servlet instance for which this event occurred.
370      */
371     private Wrapper wrapper = null;
372 
373 
374     // ------------------------------------------------------------- Properties
375 
376 
377     /**
378      * Return the exception that occurred during the processing
379      * that was reported by this event.
380      */
381     public Throwable   getException() {
382 
383         return (this.exception);
384 
385     }
386 
387 
388     /**
389      * Return the filter instance for which this event occurred.
390      */
391     public Filter   getFilter() {
392 
393         return (this.filter);
394 
395     }
396 
397 
398     /**
399      * Return the servlet request for which this event occurred.
400      */
401     public ServletRequest   getRequest() {
402 
403         return (this.request);
404 
405     }
406 
407 
408     /**
409      * Return the servlet response for which this event occurred.
410      */
411     public ServletResponse   getResponse() {
412 
413         return (this.response);
414 
415     }
416 
417 
418     /**
419      * Return the servlet instance for which this event occurred.
420      */
421     public Servlet   getServlet() {
422 
423         return (this.servlet);
424 
425     }
426 
427 
428     /**
429      * Return the event type of this event.
430      */
431     public String   getType() {
432 
433         return (this.type);
434 
435     }
436 
437 
438     /**
439      * Return the Wrapper managing the servlet instance for which this
440      * event occurred.
441      */
442     public Wrapper getWrapper() {
443 
444         return (this.wrapper);
445 
446     }
447 
448 
449 }
450
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