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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
44   * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
45   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
46   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
47   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
48   * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
49   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
50   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
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  
61  import com.sun.org.apache.bcel.internal.classfile.*;
62  
63  /**
64   * This class represents a line number within a method, i.e., give an instruction
65   * a line number corresponding to the source code line.
66   *
67   * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
68   * @see     LineNumber
69   * @see     MethodGen
70   */
71  public class LineNumberGen
72    implements InstructionTargeter, Cloneable, java.io.Serializable
73  {
74    private InstructionHandle ih;
75    private int               src_line;
76  
77    /**
78     * Create a line number.
79     *
80     * @param ih instruction handle to reference
81     */
82    public LineNumberGen(InstructionHandle ih, int src_line) {
83      setInstruction(ih);
84      setSourceLine(src_line);
85    }
86  
87    /**
88     * @return true, if ih is target of this line number
89     */
90    @Override
91    public boolean containsTarget(InstructionHandle ih) {
92      return this.ih == ih;
93    }
94  
95    /**
96     * @param old_ih old target
97     * @param new_ih new target
98     */
99    @Override
100   public void updateTarget(InstructionHandle old_ih, InstructionHandle new_ih) {
101     if(old_ih != ih)
102       throw new ClassGenException("Not targeting " + old_ih + ", but " + ih + "}");
103     else
104       setInstruction(new_ih);
105   }
106 
107   /**
108    * Get LineNumber attribute .
109    *
110    * This relies on that the instruction list has already been dumped to byte code or
111    * or that the `setPositions' methods has been called for the instruction list.
112    */
113   public LineNumber getLineNumber() {
114     return new LineNumber(ih.getPosition(), src_line);
115   }
116 
117   public final void setInstruction(InstructionHandle ih) {
118     BranchInstruction.notifyTargetChanging(this.ih, this);
119     this.ih = ih;
120     BranchInstruction.notifyTargetChanged(this.ih, this);
121   }
122 
123   @Override
124   public Object clone() {
125     try {
126       return super.clone();
127     } catch(CloneNotSupportedException e) {
128       System.err.println(e);
129       return null;
130     }
131   }
132 
133   public InstructionHandle getInstruction()               { return ih; }
134   public void              setSourceLine(int src_line)    { this.src_line = src_line; }
135   public int               getSourceLine()                { return src_line; }
136 }