spring中提供了两种动态代理的方式，分别是Java Proxy以及cglib
JavaProxy只能代理接口，而cglib是通过继承的方式，实现对类的代理
添加一个接口以及对应的实现类
public interface HelloInterface {
void sayHello();
}
public class HelloInterfaceImpl implements HelloInterface {
@Override
public void sayHello() {
System.out.println("hello");
}
}
JavaProxy通过实现InvocationHandler实现代理
public class CustomInvocationHandler implements InvocationHandler {
private HelloInterface helloInterface;
public CustomInvocationHandler(HelloInterface helloInterface) {
this.helloInterface = helloInterface;
}
@Override
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
System.out.println("before hello for proxy");
Object result = method.invoke(helloInterface, args);
System.out.println("after hello for proxy");
return result;
}
}
而cglib实现MethodInterceptor进行方法上的代理
public class CustomMethodInterceptor implements MethodInterceptor {
@Override
public Object intercept(Object o, Method method, Object[] objects, MethodProxy methodProxy) throws Throwable {
System.out.println("before hello for cglib");
Object result = methodProxy.invokeSuper(o, objects);
System.out.println("after hello for cglib");
return result;
}
}
分别实现调用代码
public static void main(String[] args) {
Enhancer enhancer = new Enhancer();
enhancer.setSuperclass(HelloInterfaceImpl.class);
enhancer.setCallback(new CustomMethodInterceptor());
HelloInterface target = (HelloInterface) enhancer.create();
target.sayHello();
CustomInvocationHandler invocationHandler = new CustomInvocationHandler(new HelloInterfaceImpl());
HelloInterface target2 = (HelloInterface) Proxy.newProxyInstance(Demo.class.getClassLoader(), new Class[]{HelloInterface.class}, invocationHandler);
target2.sayHello();
}
可以看到对于的代理信息输出
before hello for cglib hello after hello for cglib before hello for proxy hello after hello for proxy
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。
