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Java > Open Source Codes > com > sun > org > apache > bcel > internal > classfile > CodeException


1 package com.sun.org.apache.bcel.internal.classfile;
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.Constants;
58 import java.io.*;
59
60 /**
61  * This class represents an entry in the exception table of the <em>Code</em>
62  * attribute and is used only there. It contains a range in which a
63  * particular exception handler is active.
64  *
65  * @version $Id: CodeException.java,v 1.1.1.1 2001/10/29 19:59:58 jvanzyl Exp $
66  * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
67  * @see Code
68  */
69 public final class CodeException implements Cloneable JavaDoc, Constants, Node {
70   private int start_pc; // Range in the code the exception handler is
71 private int end_pc; // active. start_pc is inclusive, end_pc exclusive
72 private int handler_pc; /* Starting address of exception handler, i.e.,
73                * an offset from start of code.
74                */
75   private int catch_type; /* If this is zero the handler catches any
76                * exception, otherwise it points to the
77                * exception class which is to be caught.
78                */
79   /**
80    * Initialize from another object.
81    */
82   public CodeException(CodeException c) {
83     this(c.getStartPC(), c.getEndPC(), c.getHandlerPC(), c.getCatchType());
84   }
85
86   /**
87    * Construct object from file stream.
88    * @param file Input stream
89    * @throw IOException
90    */
91   CodeException(DataInputStream file) throws IOException
92   {
93     this(file.readUnsignedShort(), file.readUnsignedShort(),
94      file.readUnsignedShort(), file.readUnsignedShort());
95   }
96
97   /**
98    * @param start_pc Range in the code the exception handler is active,
99    * start_pc is inclusive while
100    * @param end_pc is exclusive
101    * @param handler_pc Starting address of exception handler, i.e.,
102    * an offset from start of code.
103    * @param catch_type If zero the handler catches any
104    * exception, otherwise it points to the exception class which is
105    * to be caught.
106    */
107   public CodeException(int start_pc, int end_pc, int handler_pc,
108                int catch_type)
109   {
110     this.start_pc = start_pc;
111     this.end_pc = end_pc;
112     this.handler_pc = handler_pc;
113     this.catch_type = catch_type;
114   }
115
116   /**
117    * Called by objects that are traversing the nodes of the tree implicitely
118    * defined by the contents of a Java class. I.e., the hierarchy of methods,
119    * fields, attributes, etc. spawns a tree of objects.
120    *
121    * @param v Visitor object
122    */
123   public void accept(Visitor v) {
124     v.visitCodeException(this);
125   }
126   /**
127    * Dump code exception to file stream in binary format.
128    *
129    * @param file Output file stream
130    * @throw IOException
131    */
132   public final void dump(DataOutputStream file) throws IOException
133   {
134     file.writeShort(start_pc);
135     file.writeShort(end_pc);
136     file.writeShort(handler_pc);
137     file.writeShort(catch_type);
138   }
139
140   /**
141    * @return 0, if the handler catches any exception, otherwise it points to
142    * the exception class which is to be caught.
143    */
144   public final int getCatchType() { return catch_type; }
145
146   /**
147    * @return Exclusive end index of the region where the handler is active.
148    */
149   public final int getEndPC() { return end_pc; }
150
151   /**
152    * @return Starting address of exception handler, relative to the code.
153    */
154   public final int getHandlerPC() { return handler_pc; }
155
156   /**
157    * @return Inclusive start index of the region where the handler is active.
158    */
159   public final int getStartPC() { return start_pc; }
160
161   /**
162    * @param catch_type.
163    */
164   public final void setCatchType(int catch_type) {
165     this.catch_type = catch_type;
166   }
167
168   /**
169    * @param end_pc end of handled block
170    */
171   public final void setEndPC(int end_pc) {
172     this.end_pc = end_pc;
173   }
174
175   /**
176    * @param handler_pc where the actual code is
177    */
178   public final void setHandlerPC(int handler_pc) {
179     this.handler_pc = handler_pc;
180   }
181
182   /**
183    * @param start_pc start of handled block
184    */
185   public final void setStartPC(int start_pc) {
186     this.start_pc = start_pc;
187   }
188
189   /**
190    * @return String representation.
191    */
192   public final String JavaDoc toString() {
193     return "CodeException(start_pc = " + start_pc +
194       ", end_pc = " + end_pc +
195       ", handler_pc = " + handler_pc + ", catch_type = " + catch_type + ")";
196   }
197
198   /**
199    * @return String representation.
200    */
201   public final String JavaDoc toString(ConstantPool cp, boolean verbose) {
202     String JavaDoc str;
203
204     if(catch_type == 0)
205       str = "<Any exception>(0)";
206     else
207       str = Utility.compactClassName(cp.getConstantString(catch_type, CONSTANT_Class), false) +
208     (verbose? "(" + catch_type + ")" : "");
209
210     return start_pc + "\t" + end_pc + "\t" + handler_pc + "\t" + str;
211   }
212
213   public final String JavaDoc toString(ConstantPool cp) {
214     return toString(cp, true);
215   }
216
217   /**
218    * @return deep copy of this object
219    */
220   public CodeException copy() {
221     try {
222       return (CodeException)clone();
223     } catch(CloneNotSupportedException JavaDoc e) {}
224
225     return null;
226   }
227 }
228
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