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Java > Open Source Codes > org > apache > bsf > util > BSFEventProcessor


1 /*
2  * The Apache Software License, Version 1.1
3  *
4  * Copyright (c) 2002 The Apache Software Foundation. All rights
5  * reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  * notice, this list of conditions and the following disclaimer.
13  *
14  * 2. Redistributions in binary form must reproduce the above copyright
15  * notice, this list of conditions and the following disclaimer in
16  * the documentation and/or other materials provided with the
17  * distribution.
18  *
19  * 3. The end-user documentation included with the redistribution, if
20  * any, must include the following acknowlegement:
21  * "This product includes software developed by the
22  * Apache Software Foundation (http://www.apache.org/)."
23  * Alternately, this acknowlegement may appear in the software itself,
24  * if and wherever such third-party acknowlegements normally appear.
25  *
26  * 4. The names "Apache BSF", "Apache", and "Apache Software Foundation"
27  * must not be used to endorse or promote products derived from
28  * this software without prior written permission. For written
29  * permission, please contact apache@apache.org.
30  *
31  * 5. Products derived from this software may not be called "Apache"
32  * nor may "Apache" appear in their names without prior written
33  * permission of the Apache Group.
34  *
35  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
36  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
37  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
38  * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
39  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
40  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
41  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
42  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
43  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
44  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
45  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
46  * SUCH DAMAGE.
47  * ====================================================================
48  *
49  * This software consists of voluntary contributions made by many individuals
50  * on behalf of the Apache Software Foundation and was originally created by
51  * Sanjiva Weerawarana and others at International Business Machines
52  * Corporation. For more information on the Apache Software Foundation,
53  * please see <http://www.apache.org/>.
54  */
55
56 package org.apache.bsf.util;
57
58 import org.apache.bsf.util.event.*;
59 import org.apache.bsf.*;
60 import java.io.PrintStream JavaDoc;
61
62 /**
63  * This is used to support binding scripts to be run when an event
64  * occurs.
65  *
66  * @author Sanjiva Weerawarana
67  */
68 public class BSFEventProcessor implements EventProcessor {
69   BSFEngine engine;
70   BSFManager manager;
71   String JavaDoc filter;
72   String JavaDoc source;
73   int lineNo;
74   int columnNo;
75   Object JavaDoc script;
76
77   /**
78    * Package-protected constructor makes this class unavailable for
79    * public use.
80    */
81   BSFEventProcessor (BSFEngine engine, BSFManager manager, String JavaDoc filter,
82              String JavaDoc source, int lineNo, int columnNo, Object JavaDoc script)
83        throws BSFException {
84     this.engine = engine;
85     this.manager = manager;
86     this.filter = filter;
87     this.source = source;
88     this.lineNo = lineNo;
89     this.columnNo = columnNo;
90     this.script = script;
91   }
92   //////////////////////////////////////////////////////////////////////////
93 //
94 // event is delegated to me by the adapters using this. inFilter is
95 // in general the name of the method via which the event was received
96 // at the adapter. For prop/veto change events, inFilter is the name
97 // of the property. In any case, in the event processor, I only forward
98 // those events if for which the filters match (if one is specified).
99
100   public void processEvent (String JavaDoc inFilter, Object JavaDoc[] evtInfo) {
101     try {
102       processExceptionableEvent (inFilter, evtInfo);
103     } catch (RuntimeException JavaDoc re) {
104       // rethrow this .. I don't want to intercept run-time stuff
105 // that can in fact occur legit
106 throw re;
107     } catch (Exception JavaDoc e) {
108       // should not occur
109 System.err.println ("BSFError: non-exceptionable event delivery " +
110               "threw exception (that's not nice): " + e);
111       e.printStackTrace ();
112     }
113   }
114   //////////////////////////////////////////////////////////////////////////
115 //
116 // same as above, but used when the method event method may generate
117 // an exception which must go all the way back to the source (as in
118 // the vetoableChange case)
119
120   public void processExceptionableEvent (String JavaDoc inFilter, Object JavaDoc[] evtInfo)
121                                                          throws Exception JavaDoc {
122     if ((filter != null) && !filter.equals (inFilter)) {
123       // ignore this event
124 return;
125     }
126
127     // run the script
128 engine.exec (source, lineNo, columnNo, script);
129   }
130 }
131
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