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1   /*
2    * reserved comment block
3    * DO NOT REMOVE OR ALTER!
4    */
5   package com.sun.org.apache.bcel.internal.generic;
6   
7   /* ====================================================================
8    * The Apache Software License, Version 1.1
9    *
10   * Copyright (c) 2001 The Apache Software Foundation.  All rights
11   * reserved.
12   *
13   * Redistribution and use in source and binary forms, with or without
14   * modification, are permitted provided that the following conditions
15   * are met:
16   *
17   * 1. Redistributions of source code must retain the above copyright
18   *    notice, this list of conditions and the following disclaimer.
19   *
20   * 2. Redistributions in binary form must reproduce the above copyright
21   *    notice, this list of conditions and the following disclaimer in
22   *    the documentation and/or other materials provided with the
23   *    distribution.
24   *
25   * 3. The end-user documentation included with the redistribution,
26   *    if any, must include the following acknowledgment:
27   *       "This product includes software developed by the
28   *        Apache Software Foundation (http://www.apache.org/)."
29   *    Alternately, this acknowledgment may appear in the software itself,
30   *    if and wherever such third-party acknowledgments normally appear.
31   *
32   * 4. The names "Apache" and "Apache Software Foundation" and
33   *    "Apache BCEL" must not be used to endorse or promote products
34   *    derived from this software without prior written permission. For
35   *    written permission, please contact apache@apache.org.
36   *
37   * 5. Products derived from this software may not be called "Apache",
38   *    "Apache BCEL", nor may "Apache" appear in their name, without
39   *    prior written permission of the Apache Software Foundation.
40   *
41   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
42   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
43   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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47   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
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49   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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51   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52   * SUCH DAMAGE.
53   * ====================================================================
54   *
55   * This software consists of voluntary contributions made by many
56   * individuals on behalf of the Apache Software Foundation.  For more
57   * information on the Apache Software Foundation, please see
58   * <http://www.apache.org/>.
59   */
60  import java.io.*;
61  import com.sun.org.apache.bcel.internal.util.ByteSequence;
62  
63  /**
64   * LOOKUPSWITCH - Switch with unordered set of values
65   *
66   * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
67   * @see SWITCH
68   */
69  public class LOOKUPSWITCH extends Select {
70    /**
71     * Empty constructor needed for the Class.newInstance() statement in
72     * Instruction.readInstruction(). Not to be used otherwise.
73     */
74    LOOKUPSWITCH() {}
75  
76    public LOOKUPSWITCH(int[] match, InstructionHandle[] targets,
77                        InstructionHandle target) {
78      super(com.sun.org.apache.bcel.internal.Constants.LOOKUPSWITCH, match, targets, target);
79  
80      length = (short)(9 + match_length * 8); /* alignment remainder assumed
81                                               * 0 here, until dump time. */
82      fixed_length = length;
83    }
84  
85    /**
86     * Dump instruction as byte code to stream out.
87     * @param out Output stream
88     */
89    public void dump(DataOutputStream out) throws IOException {
90      super.dump(out);
91      out.writeInt(match_length);       // npairs
92  
93      for(int i=0; i < match_length; i++) {
94        out.writeInt(match[i]);         // match-offset pairs
95        out.writeInt(indices[i] = getTargetOffset(targets[i]));
96      }
97    }
98  
99    /**
100    * Read needed data (e.g. index) from file.
101    */
102   protected void initFromFile(ByteSequence bytes, boolean wide) throws IOException
103   {
104     super.initFromFile(bytes, wide); // reads padding
105 
106     match_length = bytes.readInt();
107     fixed_length = (short)(9 + match_length * 8);
108     length       = (short)(fixed_length + padding);
109 
110     match   = new int[match_length];
111     indices = new int[match_length];
112     targets = new InstructionHandle[match_length];
113 
114     for(int i=0; i < match_length; i++) {
115       match[i]   = bytes.readInt();
116       indices[i] = bytes.readInt();
117     }
118   }
119 
120 
121   /**
122    * Call corresponding visitor method(s). The order is:
123    * Call visitor methods of implemented interfaces first, then
124    * call methods according to the class hierarchy in descending order,
125    * i.e., the most specific visitXXX() call comes last.
126    *
127    * @param v Visitor object
128    */
129   public void accept(Visitor v) {
130     v.visitVariableLengthInstruction(this);
131     v.visitStackProducer(this);
132     v.visitBranchInstruction(this);
133     v.visitSelect(this);
134     v.visitLOOKUPSWITCH(this);
135   }
136 }