org.objectweb.asm.util

Class TraceClassVisitor

public class TraceClassVisitor extends PrintClassVisitor

A {@link PrintClassVisitor PrintClassVisitor} that prints a disassembled view of the classes it visits. This class visitor can be used alone (see the {@link #main main} method) to disassemble a class. It can also be used in the middle of class visitor chain to trace the class that is visited at a given point in this chain. This may be uselful for debugging purposes.

The trace printed when visiting the Hello class is the following:

 // compiled from Hello.java
 public class Hello {

   public static main ([Ljava/lang/String;)V
     GETSTATIC java/lang/System out Ljava/io/PrintStream;
     LDC "hello"
     INVOKEVIRTUAL java/io/PrintStream println (Ljava/lang/String;)V
     RETURN
     MAXSTACK = 2
     MAXLOCALS = 1

   public <init> ()V
     ALOAD 0
     INVOKESPECIAL java/lang/Object <init> ()V
     RETURN
     MAXSTACK = 1
     MAXLOCALS = 1

 }
 
where Hello is defined by:

 public class Hello {

   public static void main (String[] args) {
     System.out.println("hello");
   }
 }
 

Author: Eric Bruneton, Eugene Kuleshov

Field Summary
protected ClassVisitorcv
The {@link ClassVisitor ClassVisitor} to which this visitor delegates calls.
Constructor Summary
TraceClassVisitor(ClassVisitor cv, PrintWriter pw)
Constructs a new {@link TraceClassVisitor TraceClassVisitor} object.
Method Summary
static voidmain(String[] args)
Prints a disassembled view of the given class to the standard output.
voidvisit(int version, int access, String name, String superName, String[] interfaces, String sourceFile)
voidvisitAttribute(Attribute attr)
voidvisitEnd()
voidvisitField(int access, String name, String desc, Object value, Attribute attrs)
voidvisitInnerClass(String name, String outerName, String innerName, int access)
CodeVisitorvisitMethod(int access, String name, String desc, String[] exceptions, Attribute attrs)

Field Detail

cv

protected final ClassVisitor cv
The {@link ClassVisitor ClassVisitor} to which this visitor delegates calls. May be null.

Constructor Detail

TraceClassVisitor

public TraceClassVisitor(ClassVisitor cv, PrintWriter pw)
Constructs a new {@link TraceClassVisitor TraceClassVisitor} object.

Parameters: cv the class visitor to which this adapter must delegate calls. May be null. pw the print writer to be used to print the class.

Method Detail

main

public static void main(String[] args)
Prints a disassembled view of the given class to the standard output.

Usage: TraceClassVisitor [-debug] <fully qualified class name or class file name >

Parameters: args the command line arguments.

Throws: Exception if the class cannot be found, or if an IO exception occurs.

visit

public void visit(int version, int access, String name, String superName, String[] interfaces, String sourceFile)

visitAttribute

public void visitAttribute(Attribute attr)

visitEnd

public void visitEnd()

visitField

public void visitField(int access, String name, String desc, Object value, Attribute attrs)

visitInnerClass

public void visitInnerClass(String name, String outerName, String innerName, int access)

visitMethod

public CodeVisitor visitMethod(int access, String name, String desc, String[] exceptions, Attribute attrs)