ASM 5.2 ClassReader.accept抛出ArrayIndexOutOfBoundsException异常：2

我现在正在试图找出这个错误我们，因为几个小时，我硬是不知道可能会导致它。我正在尝试将代码注入类文件。奇怪的是，注射工作正常ClassWriter.COMPUTE_MAXS，但抛出，如果我用ClassWriter.COMPUTE_FRAMES一个ArrayIndexOutOfBoundsException。我需要使用COMPUTE_FRAMES才能运行编辑过的类。我使用ASM 5.2，只出这么远的是COMPUTE_FRAMES具有为2的值（也许这可以帮助你以某种方式）ASM 5.2 ClassReader.accept抛出ArrayIndexOutOfBoundsException异常：2

我的代码中发现：

InputStream in = new FileInputStream("Paht/To/Class.class"); 
    ClassReader classReader = new ClassReader(in); 
    ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES){ 
     @Override 
     protected String getCommonSuperClass(final String type1, final String type2){ 
      return "java/lang/Object"; 
     } 
    }; 

    ClassVisitor mcw = new ModifierClassWriter(Opcodes.ASM5, cw); 
    classReader.accept(mcw, 0); 

    File outputDir = new File("Path/To/Output/dir"); 
    outputDir.mkdirs(); 
    DataOutputStream dout = new DataOutputStream(new FileOutputStream(new File(outputDir, "NameOfFile.class"))); 
    dout.write(cw.toByteArray()); 
    dout.close();

修改方法编剧：

public static class ModifierMethodWriter extends MethodVisitor{ 

    private String methodName; 

    public ModifierMethodWriter(int api, MethodVisitor mv, String methodName) { 
     super(api, mv); 
     this.methodName = methodName; 
    } 
    @Override 
    public void visitCode() { 
     super.visitCode(); 
    //InjectCodeHere, removed it because it most likely doesnt cause the error 
    } 
}

ModifierClassWriter：

public static class ModifierClassWriter extends ClassVisitor{ 
    private int api; 
    public ModifierClassWriter(int api, ClassWriter cv) { 
     super(api, cv); 
     this.api = api; 
    } 

    @Override 
    public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) { 
     MethodVisitor mv = super.visitMethod(access, name, desc, signature, exceptions); 
     ModifierMethodWriter mvw = new ModifierMethodWriter(api, mv, name); 
     return mvw; 
    } 
}

的错误：

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 2 
at org.objectweb.asm.Frame.a(Unknown Source) 
at org.objectweb.asm.Frame.a(Unknown Source) 
at org.objectweb.asm.MethodWriter.visitMaxs(Unknown Source) 
at org.objectweb.asm.MethodVisitor.visitMaxs(Unknown Source) 
at org.objectweb.asm.ClassReader.a(Unknown Source) 
at org.objectweb.asm.ClassReader.b(Unknown Source) 
at org.objectweb.asm.ClassReader.accept(Unknown Source) 
at org.objectweb.asm.ClassReader.accept(Unknown Source) 
at package.main.ClassMaker.main(ClassMaker.java:28)

来源

2017-04-12 user3593320

你应该使用他们的编译罐子ASM的SVN isntead源。它会让你看到完整的堆栈轨迹，没有像“a”或“b”这样的名字。对于问题本身，帧生成往往在修改您在无效的字节码结果失败。 '// InjectCodeHere，去掉它，因为它很可能不导致的error'这实际上可能是什么原因造成的。 –