ASM ByteCode Instrumentation , Which Method is Executed - java-bytecode-asm

Question

I am using ASM Bytecode Library to instrument Java Classes using pre-main.
How do we get the name of the method executed?
Thanks in advance...

Answer 1

In short, there is a name parameter on corresponding visit*() method call. You'll have to produce a more specific example to get more detailed answer.

Answer 2

Attached my Code for your reference
package com.eg.agent;
import java.lang.instrument.Instrumentation;
public class Agent {
private Agent(Instrumentation instrumentation){
}
public static void premain(String agentArgs, Instrumentation inst)
{
EgClassFileTransformer egClassFileTransformer =
new EgClassFileTransformer (agentArgs , inst);
}
}
package com.eg.agent;
import java.lang.instrument.ClassFileTransformer;
import java.lang.instrument.IllegalClassFormatException;
import java.lang.instrument.Instrumentation;
import java.security.ProtectionDomain;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import org.objectweb.asm.ClassReader;
public class EgClassFileTransformer implements ClassFileTransformer {
protected String agentArgString = "";
protected Instrumentation instrumentation;
public EgClassFileTransformer(String agentArgs, Instrumentation inst){
agentArgString = agentArgs;
instrumentation = inst;
instrumentation.addTransformer(this);
}
public byte[] transform(ClassLoader loader, String className, Class<?> classBeingRedefined,
ProtectionDomain protectionDomain, byte[] classfileBuffer) throws IllegalClassFormatException
{
//System.out.println("ClassName :"+className);
InputStream in = loader.getResourceAsStream(className.replace('.', '/') + ".class");
try{
ClassReader classReader=new ClassReader(in);
String superClassName = classReader.getSuperName();
String[] interfaces = classReader.getInterfaces();
if(interfaces!=null && interfaces.length > 0){
for(int k=0;k<interfaces.length;k++){
String inface = interfaces[k];
System.out.println(" \t interface :"+inface);
}
}
//System.out.println("superClassName :"+superClassName);
ArrayList thisList = new ArrayList();
thisList.add(superClassName);
ArrayList superList = printSuperClassNames(superClassName , thisList);
System.out.println("className :"+className +" ==>"+ " superList :"+superList);
} catch (IOException e) {
//e.printStackTrace();
System.out.println("[EXECEPTION] ..."+className);
}
return null;
}
public static ArrayList printSuperClassNames(String className, ArrayList list)
{
ClassReader cr=null;
try {
cr = new ClassReader(className);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
String superName = cr.getSuperName();
//System.out.println("[superName]"+superName);
if(superName!=null && !superName.equals("java/lang/Object"))
{
list.add(superName);
String superClass = superName.replace('.', '/');
printSuperClassNames(superClass, list);
}
return list;
}
}