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      1 /*
      2  * ProGuard -- shrinking, optimization, obfuscation, and preverification
      3  *             of Java bytecode.
      4  *
      5  * Copyright (c) 2002-2009 Eric Lafortune (eric (at) graphics.cornell.edu)
      6  *
      7  * This program is free software; you can redistribute it and/or modify it
      8  * under the terms of the GNU General Public License as published by the Free
      9  * Software Foundation; either version 2 of the License, or (at your option)
     10  * any later version.
     11  *
     12  * This program is distributed in the hope that it will be useful, but WITHOUT
     13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
     14  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
     15  * more details.
     16  *
     17  * You should have received a copy of the GNU General Public License along
     18  * with this program; if not, write to the Free Software Foundation, Inc.,
     19  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
     20  */
     21 package proguard.classfile;
     22 
     23 
     24 import proguard.classfile.attribute.*;
     25 import proguard.classfile.attribute.visitor.AttributeVisitor;
     26 import proguard.classfile.visitor.MemberVisitor;
     27 
     28 /**
     29  * Representation of a field or method from a program class.
     30  *
     31  * @author Eric Lafortune
     32  */
     33 public abstract class ProgramMember implements Member
     34 {
     35     public int         u2accessFlags;
     36     public int         u2nameIndex;
     37     public int         u2descriptorIndex;
     38     public int         u2attributesCount;
     39     public Attribute[] attributes;
     40 
     41     /**
     42      * An extra field in which visitors can store information.
     43      */
     44     public Object visitorInfo;
     45 
     46 
     47     /**
     48      * Creates an uninitialized ProgramMember.
     49      */
     50     protected ProgramMember()
     51     {
     52     }
     53 
     54 
     55     /**
     56      * Creates an initialized ProgramMember.
     57      */
     58     protected ProgramMember(int         u2accessFlags,
     59                             int         u2nameIndex,
     60                             int         u2descriptorIndex,
     61                             int         u2attributesCount,
     62                             Attribute[] attributes)
     63     {
     64         this.u2accessFlags     = u2accessFlags;
     65         this.u2nameIndex       = u2nameIndex;
     66         this.u2descriptorIndex = u2descriptorIndex;
     67         this.u2attributesCount = u2attributesCount;
     68         this.attributes        = attributes;
     69     }
     70 
     71 
     72     /**
     73      * Returns the line number range of the given class member as "m:n",
     74      * if it can find it, or <code>null</code> otherwise.
     75      */
     76     public String getLineNumberRange(Clazz clazz)
     77     {
     78         CodeAttribute codeAttribute =
     79             (CodeAttribute)getAttribute(clazz, ClassConstants.ATTR_Code);
     80         if (codeAttribute  == null)
     81         {
     82             return null;
     83         }
     84 
     85         LineNumberTableAttribute lineNumberTableAttribute =
     86             (LineNumberTableAttribute)codeAttribute.getAttribute(clazz,
     87                                                                  ClassConstants.ATTR_LineNumberTable);
     88         if (lineNumberTableAttribute  == null)
     89         {
     90             return null;
     91         }
     92 
     93         return "" +
     94                lineNumberTableAttribute.getLineNumber(0) +
     95                ":" +
     96                lineNumberTableAttribute.getLineNumber(Integer.MAX_VALUE);
     97     }
     98 
     99 
    100     /**
    101      * Returns the (first) attribute with the given name.
    102      */
    103     private Attribute getAttribute(Clazz clazz, String name)
    104     {
    105         for (int index = 0; index < u2attributesCount; index++)
    106         {
    107             Attribute attribute = attributes[index];
    108             if (attribute.getAttributeName(clazz).equals(name))
    109             {
    110                 return attribute;
    111             }
    112         }
    113 
    114         return null;
    115     }
    116 
    117 
    118     /**
    119      * Accepts the given member info visitor.
    120      */
    121     public abstract void accept(ProgramClass  programClass,
    122                                 MemberVisitor memberVisitor);
    123 
    124 
    125 
    126     /**
    127      * Lets the given attribute info visitor visit all the attributes of
    128      * this member info.
    129      */
    130     public abstract void attributesAccept(ProgramClass     programClass,
    131                                           AttributeVisitor attributeVisitor);
    132 
    133 
    134     // Implementations for Member.
    135 
    136     public int getAccessFlags()
    137     {
    138         return u2accessFlags;
    139     }
    140 
    141     public String getName(Clazz clazz)
    142     {
    143         return clazz.getString(u2nameIndex);
    144     }
    145 
    146     public String getDescriptor(Clazz clazz)
    147     {
    148         return clazz.getString(u2descriptorIndex);
    149     }
    150 
    151     public void accept(Clazz clazz, MemberVisitor memberVisitor)
    152     {
    153         accept((ProgramClass)clazz, memberVisitor);
    154     }
    155 
    156 
    157     // Implementations for VisitorAccepter.
    158 
    159     public Object getVisitorInfo()
    160     {
    161         return visitorInfo;
    162     }
    163 
    164     public void setVisitorInfo(Object visitorInfo)
    165     {
    166         this.visitorInfo = visitorInfo;
    167     }
    168 }
    169