1   package org.apache.bcel.generic;
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  import java.io.*;
57  import org.apache.bcel.util.ByteSequence;
58  
59  /*** 
60   * TABLESWITCH - Switch within given range of values, i.e., low..high
61   *
62   * @version $Id: TABLESWITCH.java,v 1.1.1.1 2001/10/29 20:00:27 jvanzyl Exp $
63   * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
64   * @see SWITCH
65   */
66  public class TABLESWITCH extends Select {
67    /***
68     * Empty constructor needed for the Class.newInstance() statement in
69     * Instruction.readInstruction(). Not to be used otherwise.
70     */
71    TABLESWITCH() {}
72  
73    /***
74     * @param match sorted array of match values, match[0] must be low value, 
75     * match[match_length - 1] high value
76     * @param targets where to branch for matched values
77     * @param target default branch
78     */
79    public TABLESWITCH(int[] match, InstructionHandle[] targets,
80  		     InstructionHandle target) {
81      super(org.apache.bcel.Constants.TABLESWITCH, match, targets, target);
82      
83      length = (short)(13 + match_length * 4); /* Alignment remainder assumed
84  					      * 0 here, until dump time */
85      fixed_length = length;
86    }
87  
88    /***
89     * Dump instruction as byte code to stream out.
90     * @param out Output stream
91     */
92    public void dump(DataOutputStream out) throws IOException {
93      super.dump(out);
94  
95      int low = (match_length > 0)? match[0] : 0;
96      out.writeInt(low);
97  
98      int high = (match_length > 0)? match[match_length - 1] : 0;
99      out.writeInt(high);
100 
101     for(int i=0; i < match_length; i++)     // jump offsets
102       out.writeInt(indices[i] = getTargetOffset(targets[i]));
103   }
104 
105   /***
106    * Read needed data (e.g. index) from file.
107    */
108   protected void initFromFile(ByteSequence bytes, boolean wide) throws IOException
109   {
110     super.initFromFile(bytes, wide);
111 
112     int low    = bytes.readInt();
113     int high   = bytes.readInt();
114 
115     match_length = high - low + 1;
116     fixed_length = (short)(13 + match_length * 4);
117     length       = (short)(fixed_length + padding);
118 
119     match   = new int[match_length];
120     indices = new int[match_length];
121     targets = new InstructionHandle[match_length];
122 
123     for(int i=low; i <= high; i++)
124       match[i - low] = i;
125 
126     for(int i=0; i < match_length; i++) {
127       indices[i] = bytes.readInt();
128     }
129   }
130 
131 
132   /***
133    * Call corresponding visitor method(s). The order is:
134    * Call visitor methods of implemented interfaces first, then
135    * call methods according to the class hierarchy in descending order,
136    * i.e., the most specific visitXXX() call comes last.
137    *
138    * @param v Visitor object
139    */
140   public void accept(Visitor v) {
141     v.visitVariableLengthInstruction(this);
142     v.visitStackProducer(this);
143     v.visitBranchInstruction(this);
144     v.visitSelect(this);
145     v.visitTABLESWITCH(this);
146   }
147 }
This page was automatically generated by Maven