Spring三种实现自动代理

Spring三种实现自动代理

1.基于bean配置名规则的自动代理创建器：允许为一组特定配置名的bean自动创建代理实例的代理创建器，实现类为：BeanNameAutoProxyCreator

2.基于Advisor匹配机制的自动代理创建器，实现类为:DefaultAdvisorAutoProxyCreator

3.基于bean中的AspectJ注解标签的自动代理创建器

第一种：

Waiter类：

package aop.beannameauto;public class Waiter {public void greet(String name) {System.out.println("Waiter.greet()"+name);}}

前置方法增强：

package aop.beannameauto;import java.lang.reflect.Method;import org.springframework.aop.MethodBeforeAdvice;public class GreetB implements MethodBeforeAdvice{@Overridepublic void before(Method arg0, Object[] arg1, Object arg2)throws Throwable {// TODO Auto-generated method stubString name= (String) arg1[0];System.out.println("GreetB.before()"+name);}}

XML配置文件：

<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xmlns:p="http://www.springframework.org/schema/p"xmlns:aop="http://www.springframework.org/schema/aop"xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd           http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.1.xsd"><bean id="waiter" class="aop.beannameauto.Waiter" /><bean id="greetingAdvice" class="aop.beannameauto.GreetB" />                      <beanclass="org.springframework.aop.framework.autoproxy.BeanNameAutoProxyCreator"p:beanNames="*er" p:interceptorNames="greetingAdvice"p:optimize="true"/>           </beans>

BeanNameAutoProxyCreator有一个beanname属性，允许用户指定一组需要自动代理的bean名称

测试类：

package aop.beannameauto;import static org.junit.Assert.*;import org.junit.Test;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;public class BeanTest {@Testpublic void test() {ApplicationContext context = new ClassPathXmlApplicationContext("aop/beannameauto/beans.xml");Waiter waiter = (Waiter) context.getBean("waiter");waiter.greet("11");}}

第二种：

Waiter类和增强类同上

配置文件：

<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd"><bean id="waiter" class="aop.defaultauto.Waiter" /><bean id="greetingAdvice" class="aop.defaultauto.GreetB" /><bean id="regexpAdvisor"class="org.springframework.aop.support.RegexpMethodPointcutAdvisor"p:patterns=".*greet.*" p:advice-ref="greetingAdvice" /><beanclass="org.springframework.aop.framework.autoproxy.DefaultAdvisorAutoProxyCreator" /></beans>

测试类：

package aop.defaultauto;import static org.junit.Assert.*;import org.junit.Test;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;public class BeanTest {@Testpublic void test() {ApplicationContext context = new ClassPathXmlApplicationContext("aop/defaultauto/beans.xml");Waiter waiter = (Waiter) context.getBean("waiter");waiter.greet("11");}}

第三种：

Waiter类同上

增强类：

package aop.aspect;import org.aspectj.lang.annotation.Aspect;import org.aspectj.lang.annotation.Before;@Aspectpublic class GreetB {@Before("execution(* greet(..))")public void before() {System.out.println("GreetB.before()");}}

在类处标注了@AspectJ注解，第三方处理程序就可以通过类是否拥有@AspectJ注解判断是否为一个切面

其次，在方法定义出标注了@Before注解，并为该注解提供了成员值"execution(* greet(..))"，提供了两个信息：@Before表示前置增强，成员值是一个@AspectJ切点表达式，意思在目标类的greet方法上织入增强

测试类：

package aop.aspect;import static org.junit.Assert.*;import org.junit.Test;import org.springframework.aop.aspectj.annotation.AspectJProxyFactory;public class AspectTest {@Testpublic void test() {Waiter waiter = new Waiter();AspectJProxyFactory factory = new AspectJProxyFactory();factory.setTarget(waiter);factory.addAspect(GreetB.class);Waiter waiter2 = factory.getProxy();waiter2.greet("11");}}