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Java > Open Source Codes > com > sun > org > apache > bcel > internal > verifier > structurals > ExceptionHandlers


1 package com.sun.org.apache.bcel.internal.verifier.structurals;
2
3 /* ====================================================================
4  * The Apache Software License, Version 1.1
5  *
6  * Copyright (c) 2001 The Apache Software Foundation. All rights
7  * reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright
14  * notice, this list of conditions and the following disclaimer.
15  *
16  * 2. Redistributions in binary form must reproduce the above copyright
17  * notice, this list of conditions and the following disclaimer in
18  * the documentation and/or other materials provided with the
19  * distribution.
20  *
21  * 3. The end-user documentation included with the redistribution,
22  * if any, must include the following acknowledgment:
23  * "This product includes software developed by the
24  * Apache Software Foundation (http://www.apache.org/)."
25  * Alternately, this acknowledgment may appear in the software itself,
26  * if and wherever such third-party acknowledgments normally appear.
27  *
28  * 4. The names "Apache" and "Apache Software Foundation" and
29  * "Apache BCEL" must not be used to endorse or promote products
30  * derived from this software without prior written permission. For
31  * written permission, please contact apache@apache.org.
32  *
33  * 5. Products derived from this software may not be called "Apache",
34  * "Apache BCEL", nor may "Apache" appear in their name, without
35  * prior written permission of the Apache Software Foundation.
36  *
37  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
38  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
39  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
40  * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
41  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
42  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
43  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
44  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
45  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
46  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
47  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
48  * SUCH DAMAGE.
49  * ====================================================================
50  *
51  * This software consists of voluntary contributions made by many
52  * individuals on behalf of the Apache Software Foundation. For more
53  * information on the Apache Software Foundation, please see
54  * <http://www.apache.org/>.
55  */
56
57 import com.sun.org.apache.bcel.internal.generic.*;
58 import java.util.HashSet JavaDoc;
59 import java.util.Hashtable JavaDoc;
60
61 /**
62  * This class allows easy access to ExceptionHandler objects.
63  *
64  * @version $Id: ExceptionHandlers.java,v 1.1.1.1 2001/10/29 20:00:38 jvanzyl Exp $
65  * @author <A HREF="http://www.inf.fu-berlin.de/~ehaase"/>Enver Haase</A>
66  */
67 public class ExceptionHandlers{
68     /**
69      * The ExceptionHandler instances.
70      * Key: InstructionHandle objects, Values: HashSet<ExceptionHandler> instances.
71      */
72     private Hashtable JavaDoc exceptionhandlers;
73      
74     /**
75      * Constructor. Creates a new ExceptionHandlers instance.
76      */
77     public ExceptionHandlers(MethodGen mg){
78         exceptionhandlers = new Hashtable JavaDoc();
79         CodeExceptionGen[] cegs = mg.getExceptionHandlers();
80         for (int i=0; i<cegs.length; i++){
81             ExceptionHandler eh = new ExceptionHandler(cegs[i].getCatchType(), cegs[i].getHandlerPC());
82             for (InstructionHandle ih=cegs[i].getStartPC(); ih != cegs[i].getEndPC().getNext(); ih=ih.getNext()){
83                 HashSet JavaDoc hs;
84                 hs = (HashSet JavaDoc) exceptionhandlers.get(ih);
85                 if (hs == null){
86                     hs = new HashSet JavaDoc();
87                     exceptionhandlers.put(ih, hs);
88                 }
89                 hs.add(eh);
90             }
91         }
92     }
93     
94     /**
95      * Returns all the ExceptionHandler instances representing exception
96      * handlers that protect the instruction ih.
97      */
98     public ExceptionHandler[] getExceptionHandlers(InstructionHandle ih){
99         HashSet JavaDoc hs = (HashSet JavaDoc) exceptionhandlers.get(ih);
100         if (hs == null) return new ExceptionHandler[0];
101         else{
102             ExceptionHandler[] ret = new ExceptionHandler[hs.size()];
103             return (ExceptionHandler[]) (hs.toArray(ret));
104         }
105     }
106
107 }
108
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