如何使用ASM库访问方法变量值和方法中用户定义的对象变量的值？

import org.objectweb.asm.ClassReader;
import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;

public class VariableVisitor extends ClassVisitor {
    public VariableVisitor(ClassVisitor cv) {
        super(Opcodes.ASM7, cv);
    }

    @Override
    public MethodVisitor visitMethod(int access, String name, String descriptor, String signature, String[] exceptions) {
        MethodVisitor mv = cv.visitMethod(access, name, descriptor, signature, exceptions);
        return new MethodVisitor(Opcodes.ASM7, mv) {
            @Override
            public void visitLocalVariable(String name, String descriptor, String signature, Label start, Label end, int index) {
                // 访问方法的局部变量
                System.out.println("Variable name: " + name);
                System.out.println("Variable type: " + descriptor);
                System.out.println("Variable index: " + index);
                super.visitLocalVariable(name, descriptor, signature, start, end, index);
            }
        };
    }
}

// 使用示例
public class MyClass {
    public static void main(String[] args) {
        try {
            ClassReader cr = new ClassReader("com.example.MyClass");
            ClassWriter cw = new ClassWriter(cr, ClassWriter.COMPUTE_MAXS);
            VariableVisitor visitor = new VariableVisitor(cw);
            cr.accept(visitor, 0);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}