jcfa/src/jp/igapyon/jcfa/JavaClassFileAnalyzer.java

   1 package jp.igapyon.jcfa;\r
   2 \r
   3 import java.io.IOException;\r
   4 \r
   5 import jp.igapyon.jcfa.util.JcfaUtil;\r
   6 \r
   7 import org.apache.bcel.Constants;\r
   8 /**\r
   9  * Apache Jakarta BCELを用いたクラスファイル(バイトコード)解析サンプル\r
  10  */\r
  11 import org.apache.bcel.classfile.ClassFormatException;\r
  12 import org.apache.bcel.classfile.ClassParser;\r
  13 import org.apache.bcel.classfile.Code;\r
  14 import org.apache.bcel.classfile.Field;\r
  15 import org.apache.bcel.classfile.JavaClass;\r
  16 import org.apache.bcel.classfile.Method;\r
  17 \r
  18 public class JavaClassFileAnalyzer {\r
  19         private static final String CLASS_MODULE = "./bin/test/TestJavaClass001.class";\r
  20 \r
  21         public static final void main(final String[] args) {\r
  22                 new JavaClassFileAnalyzer().process();\r
  23         }\r
  24 \r
  25         private final void process() {\r
  26                 try {\r
  27                         final JavaClass jc = new ClassParser(CLASS_MODULE).parse();\r
  28                         System.out.println("Classname   : " + jc.getClassName());\r
  29                         System.out.println("Parent class: " + jc.getSuperclassName());\r
  30 \r
  31                         analyzeFields(jc);\r
  32 \r
  33                         analyzeMethods(jc);\r
  34 \r
  35                 } catch (ClassFormatException e) {\r
  36                         e.printStackTrace();\r
  37                 } catch (IOException e) {\r
  38                         e.printStackTrace();\r
  39                 }\r
  40         }\r
  41 \r
  42         private void analyzeFields(final JavaClass jc) {\r
  43                 final org.apache.bcel.classfile.Field[] fields = jc.getFields();\r
  44                 for (int indexField = 0; indexField < fields.length; indexField++) {\r
  45                         final Field field = fields[indexField];\r
  46                         System.out.println("  Field:" + field.getName());\r
  47                         String access = "";\r
  48                         access += field.isPublic() ? "public " : "";\r
  49                         access += field.isAbstract() ? "abstract " : "";\r
  50                         access += field.isStatic() ? "static " : "";\r
  51                         access += field.isFinal() ? "final " : "";\r
  52                         System.out.println("    " + access);\r
  53                         System.out.println("    " + field.getSignature());\r
  54                 }\r
  55         }\r
  56 \r
  57         private void analyzeMethods(final JavaClass jc) throws IOException {\r
  58                 final org.apache.bcel.classfile.Method[] methods = jc.getMethods();\r
  59                 for (int indexMethod = 0; indexMethod < methods.length; indexMethod++) {\r
  60                         final Method method = methods[indexMethod];\r
  61                         System.out.println("  Method:" + method.getName());\r
  62                         final Code code = method.getCode();\r
  63                         if (code == null) {\r
  64                                 continue;\r
  65                         }\r
  66 \r
  67                         final byte[] codes = code.getCode();\r
  68                         for (int pc = 0; pc < codes.length; pc++) {\r
  69                                 final short opcode = JcfaUtil.byte2UnsignedByte(codes[pc]);\r
  70                                 short operands = Constants.NO_OF_OPERANDS[opcode];\r
  71                                 if (operands < 0) {\r
  72                                         System.out.println("  TODO negative value:"\r
  73                                                         + Constants.OPCODE_NAMES[opcode] + ": " + operands);\r
  74                                         // break;\r
  75                                 }\r
  76 \r
  77                                 switch (opcode) {\r
  78                                 case Constants.RETURN: {\r
  79                                         System.out.println("    " + pc + ": "\r
  80                                                         + Constants.OPCODE_NAMES[opcode]);\r
  81                                         break;\r
  82                                 }\r
  83                                 case Constants.GETSTATIC: {\r
  84                                         System.out.println("    "\r
  85                                                         + pc\r
  86                                                         + ": "\r
  87                                                         + Constants.OPCODE_NAMES[opcode]\r
  88                                                         + ": "\r
  89                                                         + JcfaUtil.getConstantFieldrefString(jc,\r
  90                                                                         codes[pc + 1], codes[pc + 2]));\r
  91                                         break;\r
  92                                 }\r
  93                                 case Constants.LDC: {\r
  94                                         System.out.println("    " + pc + ": "\r
  95                                                         + Constants.OPCODE_NAMES[opcode] + ": "\r
  96                                                         + JcfaUtil.getConstantString(jc, codes[pc + 1]));\r
  97                                 }\r
  98                                         break;\r
  99                                 case Constants.INVOKEVIRTUAL:\r
 100                                 case Constants.INVOKESPECIAL: {\r
 101                                         final int operand = JcfaUtil.byte2UnsignedShort(\r
 102                                                         codes[pc + 1], codes[pc + 2]);\r
 103                                         System.out.println("    " + pc + ": "\r
 104                                                         + Constants.OPCODE_NAMES[opcode] + ": "\r
 105                                                         + JcfaUtil.getConstantMethodRefString(jc, operand));\r
 106                                 }\r
 107                                         break;\r
 108                                 case Constants.LOOKUPSWITCH:\r
 109                                         int result = JcfaUtil.byte2Int(codes[pc + 1],\r
 110                                                         codes[pc + 2], codes[pc + 3], codes[pc + 4]);\r
 111                                         System.out.println("  TODO skipping bytes: " + (result));\r
 112 \r
 113                                         int lookupOp = pc + 5;\r
 114 \r
 115                                         short diff = JcfaUtil.byte2UnsignedByte(codes[lookupOp++]);\r
 116                                         System.out.println("  TODO skipping bytes: " + (diff));\r
 117 \r
 118                                         int loopCount = JcfaUtil.byte2Int(codes[lookupOp++],\r
 119                                                         codes[lookupOp++], codes[lookupOp++],\r
 120                                                         codes[lookupOp++]);\r
 121                                         for (int index = 0; index < loopCount; index++) {\r
 122                                                 System.out.println("      "\r
 123                                                                 + JcfaUtil.byte2Int(codes[lookupOp++],\r
 124                                                                                 codes[lookupOp++], codes[lookupOp++],\r
 125                                                                                 codes[lookupOp++])\r
 126                                                                 + ":"\r
 127                                                                 + (JcfaUtil.byte2Int(codes[lookupOp++],\r
 128                                                                                 codes[lookupOp++], codes[lookupOp++],\r
 129                                                                                 codes[lookupOp++]) + pc));\r
 130                                         }\r
 131 \r
 132                                         short diff2 = JcfaUtil.byte2UnsignedByte(codes[lookupOp++]);\r
 133                                         System.out.println("  TODO skipping bytes: " + (diff2));\r
 134 \r
 135                                         operands += (lookupOp - pc);\r
 136 \r
 137                                         break;\r
 138                                 default: {\r
 139                                         System.out.println("    " + pc + ": "\r
 140                                                         + Constants.OPCODE_NAMES[opcode] + " (" + operands\r
 141                                                         + ")");\r
 142                                 }\r
 143                                         break;\r
 144                                 }\r
 145                                 pc += operands;\r
 146                         }\r
 147                 }\r
 148         }\r
 149 }