SpringFramework中ProxyFactory的用法

这篇文章主要讲解了"SpringFramework中ProxyFactory的用法"，文中的讲解内容简单清晰，易于学习与理解，下面请大家跟着小编的思路慢慢深入，一起来研究和学习"SpringFramework中ProxyFactory的用法"吧！

Spring版本是5.0.4.release.

ProxyFactory在Springaop中占有举足轻重的地位，用来间接创建代理，如下List-1所示，我们给ServiceImpl创建代理。

List-1

public interface IService {        String hello();}public class ServiceImpl implements IService {        @Override        public String hello() {                        System.out.println("service的hello方法");                        return "Hello";        }}import org.springframework.aop.MethodBeforeAdvice;import java.lang.reflect.Method;public class BeforeAdvice implements MethodBeforeAdvice {    @Override    public void before(Method method, Object[] args, Object target) throws Throwable {        System.out.println("beforeAdvice的before方法");    }}import org.springframework.aop.AfterReturningAdvice;import java.lang.reflect.Method;public class AfterAdvice implements AfterReturningAdvice {    @Override    public void afterReturning(Object returnValue, Method method, Object[] args, Object target) throws Throwable {        System.out.println("AfterAdvice的afterReturning方法");    }}import org.junit.Test;import org.springframework.aop.framework.ProxyFactory;public class AopTest {    @Test    public void test(){        ProxyFactory proxyFactory = new ProxyFactory();        proxyFactory.setInterfaces(IService.class);        proxyFactory.setTarget(new ServiceImpl());        proxyFactory.addAdvice(new BeforeAdvice());        proxyFactory.addAdvice(new AfterAdvice());        IService proxy = (IService) proxyFactory.getProxy();        String result = proxy.hello();        System.out.println(result);    }}

运行结果如下List-2

List-2

beforeAdvice的before方法service的hello方法AfterAdvice的afterReturning方法Hello

proxyFactory.addAdvice(new BeforeAdvice())时，会将Advice转换为Advisor，最后再调用addAdvisor方法。

当我们调用ProxyFactory的getProxy时，会先调用createAopProxy()->getAopProxyFactory().createAopProxy(this)，AopProxyFactory是DefaultAopProxyFactory--在另一篇里面讲到。createAopProxy方法里面把this传入，ProxyFactory实现了AdvisedSupport，所以在createAopProxy时将ProxyFactory中设置的targetSource、advice等传递到了DefaultAopProxyFactory，之后传递到JdkDynamicAopProxy中。

最后getProxy调用的是JdkDynamicAopProxy的getProxy方法，如下List-3所示，Proxy.newProxyInstance的方法中，最后的InvocationHandler是this--JdkDynamicAopProxy实现了InvocationHandler，所以当我们调用目标类的方法时，会调用JdkDynamicAopProxy的invoke方法。

List-3

public Object getProxy(@Nullable ClassLoader classLoader) {        if (logger.isDebugEnabled()) {                logger.debug("Creating JDK dynamic proxy: target source is " + this.advised.getTargetSource());        }        Class[] proxiedInterfaces = AopProxyUtils.completeProxiedInterfaces(this.advised, true);        findDefinedEqualsAndHashCodeMethods(proxiedInterfaces);        return Proxy.newProxyInstance(classLoader, proxiedInterfaces, this);}

这里就引出了一个问题，在JdkDynamicAopProxy的invoke方法中，拦截器链是怎么构造出来了。

感谢各位的阅读，以上就是"SpringFramework中ProxyFactory的用法"的内容了，经过本文的学习后，相信大家对SpringFramework中ProxyFactory的用法这一问题有了更深刻的体会，具体使用情况还需要大家实践验证。这里是，小编将为大家推送更多相关知识点的文章，欢迎关注！