jdk 和 cglib 的动态代理

jdk动态代理基于接口

public interface Fly {
    void fly();
}

public class Person implements Fly {

    @Override
    public void fly() {
        System.out.println("person fly==");
    }
}

public class Client {
    public static void main(String[] args) {

        Person person =new Person();


        Fly proxyInstance = (Fly) Proxy.newProxyInstance(Fly.class.getClassLoader(),
                Person.class.getInterfaces(),
                new InvocationHandler() {
                    @Override
                    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                        System.out.println("---before");
                        return method.invoke(person,args);
                    }
                });

        proxyInstance.fly();


    }

cglib动态代理基于继承

public final class Book {
    private String name;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
}

import org.springframework.cglib.proxy.Enhancer;
import org.springframework.cglib.proxy.MethodInterceptor;
import org.springframework.cglib.proxy.MethodProxy;

import java.lang.reflect.Method;

public class BookCglib implements MethodInterceptor {

    private Object target;

    public Object getProxy(Object target){
        this.target = target;
        Enhancer enhancer = new Enhancer();
        enhancer.setSuperclass(this.target.getClass());
        enhancer.setCallback(this);
        return enhancer.create();
    }

    @Override
    public Object intercept(Object o, Method method, Object[] objects, MethodProxy methodProxy) throws Throwable {
        System.out.println("cglib before");
        methodProxy.invokeSuper(o,objects);
        return null;
    }
}

public class CglibClient {
    public static void main(String[] args) {
        Book book = new Book();
        BookCglib bookCglib = new BookCglib();

        Book proxy = (Book) bookCglib.getProxy(book);
        String name = proxy.getName();

        System.out.println(name);

    }
}