//創(chuàng)建一個(gè)接口
public interface StudentBiz {
    int add(String name);
    void update(String name);
    void find (String name);
}

//創(chuàng)建一個(gè)類實(shí)現(xiàn)那個(gè)接口
public class StudentBizimpl implements StudentBiz{
    @Override
    public int add(String name) {
        System.out.println("調(diào)用了studentBizimpl中的add"+name);
        return 100;
    }
    @Override
    public void update(String name) {
        System.out.println("調(diào)用了studentBizimpl中的update"+name);
    }
    @Override
    public void find(String name) {
        System.out.println("調(diào)用了studentBizimpl中的find"+name);
    }
}

//jdk動(dòng)態(tài)代理三大重點(diǎn)
// 1.有目標(biāo)類的引用
// 2.有一個(gè)創(chuàng)建代理實(shí)例的方法createProxy()里面有Proxy.newProxyInstance()方法來(lái)創(chuàng)建代理實(shí)例
// 3.有一個(gè)回調(diào)方法invoke
public class LogAspect implements InvocationHandler {
    private Object target;//目標(biāo)類的對(duì)象
    public LogAspect(Object target){
        this.target=target;
    }
    public Object createProxy(){
        //新建一個(gè)代理實(shí)例
        //                           第一個(gè)參數(shù)是類加載器                        第二個(gè)是得獲取到目標(biāo)類實(shí)現(xiàn)的接口       第三個(gè)是代理類對(duì)象
        return Proxy.newProxyInstance(this.target.getClass().getClassLoader(),this.target.getClass().getInterfaces(),this);
    }
    @Override//回調(diào)方法   當(dāng)jvm調(diào)用代理對(duì)象的被代理的方法時(shí),會(huì)由jvm自動(dòng)調(diào)用這個(gè)invoke
    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
        System.out.println("代理類對(duì)象:"+proxy.getClass());
        System.out.println("目標(biāo)的方法:"+method);
        System.out.println("方法的參數(shù):"+args);
        log();//這里就可以加增強(qiáng)    具體哪些方法加得看切入點(diǎn)表達(dá)式來(lái)判斷
        Object o=method.invoke(this.target,args);//激活目標(biāo)類方法
        return o;
    }
    private void log(){
        System.out.println("前置增強(qiáng)");
    }
}

public class Test {
    public static void main(String[] args) throws IllegalAccessException, InstantiationException {
        StudentBiz sbm=new StudentBizimpl();
        LogAspect la=new LogAspect(sbm);//放目標(biāo)類對(duì)象
        Object o=la.createProxy();//創(chuàng)建一個(gè)代理類
        if (o instanceof StudentBiz){
            StudentBiz sb=(StudentBiz)o;
            sb.add("張三");//這里就會(huì)自動(dòng)回調(diào)invoke方法
        }
    }
}

//做一個(gè)cglib代理類
public class LogAspectcglib implements MethodInterceptor {
    private Object target;
    public LogAspectcglib(Object target){
        this.target=target;
    }
    public Object createProxy(){
        Enhancer enhancer=new Enhancer();//用于生成代理對(duì)象
        enhancer.setSuperclass(this.target.getClass());//設(shè)置父類
        enhancer.setCallback(this);//設(shè)置回調(diào)用對(duì)象為本身
        return enhancer.create();//創(chuàng)建代理對(duì)象
    }
    @Override
    public Object intercept(Object o, Method method, Object[] objects, MethodProxy methodProxy) throws Throwable {
        System.out.println("代理類對(duì)象"+o.getClass());
        System.out.println("目標(biāo)類的方法"+method);
        System.out.println("目標(biāo)方法參數(shù)"+objects);
        System.out.println("要代理的方法"+methodProxy);
       Object returnvalue= method.invoke(this.target,objects);
        return returnvalue;
    }
}

public class Test {
    public static void main(String[] args) throws IllegalAccessException, InstantiationException {
        StudentBizimpl sbm=new StudentBizimpl();
        LogAspectcglib lac=new LogAspectcglib(sbm);
        Object o=lac.createProxy();
        if (o instanceof StudentBizimpl){
            StudentBizimpl sb=(StudentBizimpl) o;
            sb.add("張三");
        }
    }
}

<aop:aspectj-autoproxy proxy-target-class="true"/>