ExceptionTableEntry


1   /*
2    * ExceptionTableEntry.java
3    *
4    * The contents of this file are subject to the terms of the Common Development
5    * and Distribution License (the License). You may not use this file except in
6    * compliance with the License.
7    *
8    * You can obtain a copy of the License at http://www.netbeans.org/cddl.html
9    * or http://www.netbeans.org/cddl.txt.
10   *
11   * When distributing Covered Code, include this CDDL Header Notice in each file
12   * and include the License file at http://www.netbeans.org/cddl.txt.
13   * If applicable, add the following below the CDDL Header, with the fields
14   * enclosed by brackets [] replaced by your own identifying information:
15   * "Portions Copyrighted [year] [name of copyright owner]"
16   *
17   * The Original Software is NetBeans. The Initial Developer of the Original
18   * Software is Sun Microsystems, Inc. Portions Copyright 1997-2006 Sun
19   * Microsystems, Inc. All Rights Reserved.
20   *
21   * Contributor(s): Thomas Ball
22   *
23   * Version: $Revision: 1.6 $
24   */
25  
26  package org.netbeans.modules.classfile;
27  
28  import java.io.DataInputStream  ;
29  import java.io.IOException  ;
30  
31  /**
32   * An entry in the exception table of a method's code attribute.
33   *
34   * @author  Thomas Ball
35   */
36  public final class ExceptionTableEntry {
37  
38      int startPC;
39      int endPC;
40      int handlerPC;
41      CPClassInfo catchType;  // may be null for "finally" exception handler
42  
43      static ExceptionTableEntry[] loadExceptionTable(DataInputStream   in, ConstantPool pool) 
44        throws IOException   {
45          int n = in.readUnsignedShort();
46          ExceptionTableEntry[] exceptions = new ExceptionTableEntry[n];
47          for (int i = 0; i < n; i++)
48              exceptions[i] = new ExceptionTableEntry(in, pool);
49          return exceptions;
50      }
51  
52      /** Creates new ExceptionTableEntry */
53      ExceptionTableEntry(DataInputStream   in, ConstantPool pool) 
54        throws IOException   {
55          loadExceptionEntry(in, pool);
56      }
57  
58      private void loadExceptionEntry(DataInputStream   in, ConstantPool pool) 
59        throws IOException   {
60          startPC = in.readUnsignedShort();
61          endPC = in.readUnsignedShort();
62          handlerPC = in.readUnsignedShort();
63          int typeIndex = in.readUnsignedShort();
64          if (typeIndex != 0) // may be 0 for "finally" exception handler
65          try {
66              catchType = pool.getClass(typeIndex);
67          } catch (IndexOutOfBoundsException   e) {
68              throw new InvalidClassFileAttributeException(
69                      "invalid catchType (" + typeIndex + ") in exception table entry", e);
70          }
71      }
72      
73      /**
74       * Returns the beginning offset into the method's bytecodes of this
75       * exception handler.
76       */
77      public final int getStartPC() {
78          return startPC;
79      }
80      
81      /**
82       * Returns the ending offset into the method's bytecodes of this
83       * exception handler, or the length of the bytecode array if the
84       * handler supports the method's last bytecodes (JVM 4.7.3).
85       */
86      public final int getEndPC() {
87          return endPC;
88      }
89      
90      /**
91       * Returns the starting offset into the method's bytecodes of the 
92       * exception handling code.
93       */
94      public final int getHandlerPC() {
95          return handlerPC;
96      }
97      
98      /**
99       * Returns the type of exception handler, or <code>null</code>
100      * if this handler catches all exceptions, such as an exception
101      * handler for a "<code>finally</code>" clause (JVM 4.7.3).
102      */
103     public final CPClassInfo getCatchType() {
104         return catchType;
105     }
106 }
107
A to Z: JavaDoc & Examples Daily Java News & Articles Open Source Projects Open Source Codes Free Computer Books Remove Frame
Popular Tags