spring aop拦截
.自定义被拦截的接口，且实现接口。
代码:
package demo;
public interface UserService //被拦截的接口
{
public void printUser(String user);
}
package demo;
public class UserServiceImp extends UserService //实现UserService接口
{
public void printUser(String user)
{
System.out.println("printUser user:"+user);//显示user
}
}
2 实现AOP的方法级拦截器。它可以在目标操作前后执行，拦截自定义接口的参数，或拦截接口返回的值。
代码:
package demo;
import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;
public class UserInterceptor implements MethodInterceptor
//AOP方法拦截器
{
public Object invoke(MethodInvocation arg0) throws Throwable {
try {
if (arg0.getMethod().getName().equals("printUser"))
//拦截方法是否是UserService接口的printUser方法
{
Object[] args = arg0.getArguments();//被拦截的参数
System.out.println("user:"+args[0]);
arg0.getArguments()[0]="hello!" //修改被拦截的参数
}
System.out.println(arg0.getMethod().getName() + "---!");
return arg0.proceed();//运行UserService接口的printUser方法
} catch (Exception e) {
throw e;
}
}
3. ApplicationContext.xml的设置
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">
<beans>
<bean id="userServiceImp" class="demo.UserInterceptor">
</bean>
<bean id="userService"
class="org.springframework.aop.framework.ProxyFactoryBean">
<property name="proxyInterfaces"><value>demo.UserService</value></property>
<property name="target"><ref local="userServiceImp"/></property>
<property name="interceptorNames">
<list>
<value>userInterceptor</value>
</list>
</property>
</bean>
</beans>
4.运行
package demo;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.FileSystemXmlApplicationContext;
public class DemoApp
{
public static void main(String[] args)
{
ApplicationContext ac = new FileSystemXmlApplicationContext(
"classpath:ApplicationContext.xml");
UserService us = (UserService) ac.getBean("userService");
String user="zhao";
us.printUser("zhao");
}
}
运行结果：
[java] user:zhao
[java] printUser user:hello!
转自http://www.busfly.cn/csdn/post/694.html
