Spring AOP创建BeforeAdvice和AfterAdvice实例
BeforeAdvice
1、会在目标对象的方法执行之前被调用。
2、通过实现MethodBeforeAdvice接口来实现。
3、该接口中定义了一个方法即before方法,before方法会在目标对象target之前执行。
AfterAdvice
1、在目标对象的方法执行之后被调用
2、通过实现AfterReturningAdvice接口实现
实现目标:
在方法之前调用执行某个动作。
IHello 和Hello:
1 2 3 4 5 6 7 8 9 | public interface IHello { public void sayHello(String str); } public class Hello implements IHello { @Override public void sayHello(String str) { System.out.println( "你好" +str); } } |
SayBeforeAdvice:
1 2 3 4 5 6 7 8 9 | public class SayBeforeAdvice implements MethodBeforeAdvice { @Override public void before(Method arg0, Object[] arg1, Object arg2) throws Throwable { // TODO Auto-generated method stub System.out.println( "在方法执行前做事情!" ); } } |
SayAfterAdvice文件:
1 2 3 4 5 6 7 8 9 | public class SayAfterAdvice implements AfterReturningAdvice { @Override public void afterReturning(Object arg0, Method arg1, Object[] arg2, Object arg3) throws Throwable { // TODO Auto-generated method stub System.out.println( "在方法执行后做事情!" ); } } |
applicationContext.xml:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 | <?xml version= "1.0" encoding= "UTF-8" ?> <!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN 2.0//EN" "http://www.springframework.org/dtd/spring-beans-2.0.dtd" > <beans> <!-- 建立目标对象实例 --> <bean id= "bean_hello" class = "com.pb.Hello" /> <!-- 创建执行前advice实例 --> <bean id= "sba" class = "com.pb.SayBeforeAdvice" /> <!-- 创建执行后advice实例 --> <bean id= "sfa" class = "com.pb.SayAfterAdvice" /> <!-- 建立代理对象 --> <bean id= "helloProxy" class = "org.springframework.aop.framework.ProxyFactoryBean" > <!-- 设置代理的接口 --> <property name= "proxyInterfaces" > <value>com.pb.IHello</value> </property> <!-- 设置目标对象实例 --> <property name= "target" > <ref bean= "bean_hello" /> </property> <!-- 设置Advice实例 --> <property name= "interceptorNames" > <list> <value>sba</value> <value>sfa</value> </list> </property> </bean> </beans> |
Main执行:
1 2 3 4 5 6 7 | public static void main(String[] args) { // TODO Auto-generated method stub ApplicationContext context= new ClassPathXmlApplicationContext( "applicationContext.xml" ); IHello hello=(IHello)context.getBean( "helloProxy" ); hello.sayHello( "访客" ); } |
执行效果:
人一定要靠自己