AddSecurityCheckClassAdapter.java

package com.jarvis.cache.aop.asm;

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

public class AddSecurityCheckClassAdapter extends ClassVisitor implements Opcodes {

    private String enhancedSuperName;

    public AddSecurityCheckClassAdapter(ClassVisitor cv) {
        // Responsechain 的下一个 ClassVisitor，这里我们将传入 ClassWriter，
        // 负责改写后代码的输出
        super(ASM5, cv);
    }

    @Override
    public void visit(final int version, final int access, final String name, final String signature, final String superName, final String[] interfaces) {
        String enhancedName=name + "$EnhancedByASM"; // 改变类命名
        enhancedSuperName=name; // 改变父类，这里是”Account”
        super.visit(version, access, enhancedName, signature, enhancedSuperName, interfaces);
    }

    // 重写 visitMethod，访问到 "operation" 方法时，
    // 给出自定义 MethodVisitor，实际改写方法内容
    @Override
    public MethodVisitor visitMethod(final int access, final String name, final String desc, final String signature, final String[] exceptions) {
        MethodVisitor mv=cv.visitMethod(access, name, desc, signature, exceptions);
        MethodVisitor wrappedMv=mv;
        if(mv != null) {
            if(name.equals("operation")) {
                wrappedMv=new AddSecurityCheckMethodAdapter(mv);
            } else if(name.equals("<init>")) {
                wrappedMv=new ChangeToChildConstructorMethodAdapter(mv, enhancedSuperName, desc, access);
            }
        }
        return wrappedMv;
    }
}