Spring拦截器和SpringAop实现

一、拦截器

1、aop是面向切面编程，原理是java的发射技术。

2、分为三类，before、after、arround

3、springMvc为我们提供了一个适配器HandlerInterceptorAdapter，继承它实现我们自己的拦截器

4、HandlerInterceptorAdapter例子：

package com.interceptor;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.springframework.web.servlet.ModelAndView;

import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;

public class BookInterceptor extends HandlerInterceptorAdapter {

	private static Logger Logger = LoggerFactory.getLogger(BookInterceptor.class);

	@Override

	public void afterCompletion(HttpServletRequest paramHttpServletRequest,HttpServletResponse paramHttpServletResponse, Object paramObject, Exception paramException)throws Exception {

	}

	@Override

	public void postHandle(HttpServletRequest paramHttpServletRequest, HttpServletResponse paramHttpServletResponse,Object paramObject, ModelAndView paramModelAndView) throws Exception {

		String url = paramHttpServletRequest.getRequestURI();

		Logger.info("postMethod:" + url);

	}

	@Override

	public boolean preHandle(HttpServletRequest paramHttpServletRequest, HttpServletResponse paramHttpServletResponse,Object paramObject) throws Exception {

		String url = paramHttpServletRequest.getRequestURI();

		Logger.info("preMehtod:" + url);

		return true;

	}

}

配置文件写在applicationContext.xml里面

<!--配置拦截器, 多个拦截器,顺序执行 -->

<mvc:interceptors>

	<mvc:interceptor><!-- 匹配的是url路径， 如果不配置或/**,将拦截所有的Controller -->

		<mvc:mapping path="/**" />

		<bean class="com.interceptor.BookInterceptor"></bean>

	</mvc:interceptor><!-- 当设置多个拦截器时，先按顺序调用preHandle方法，然后逆序调用每个拦截器的postHandle和afterCompletion方法 -->

</mvc:interceptors>

二、完整的切点切面

1、@aspect例子（同时定义切面和切点）

package com.interceptor;

import org.aspectj.lang.annotation.After;

import org.aspectj.lang.annotation.Aspect;

import org.aspectj.lang.annotation.Before;

import org.aspectj.lang.annotation.Pointcut;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.springframework.stereotype.Component;

@Component

@Aspect

public class BookAspect {

	private static final Logger logger = LoggerFactory.getLogger(BookAspect.class);

	@Pointcut("execution(* *.*List(..))")

	public void bookaspeck() {

	}

	@Before("bookaspeck()")

	public void bookbefore() {

		logger.info("before...");

	}

	@After("bookaspeck()")

	public void bookafter() {

		logger.info("after...");

	}

}

在applicationContext.xml中配置

<aop:aspectj-autoproxy/>

三、只有切面

1、MethodBeforeAdvice,AfterReturningAdvice只写切面，在配置文件里面定义切点

package com.interceptor;

import java.lang.reflect.Method;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.springframework.aop.AfterReturningAdvice;

import org.springframework.aop.MethodBeforeAdvice;

public class BookBeforeAdvice implements MethodBeforeAdvice,AfterReturningAdvice {

	private static Logger Logger = LoggerFactory.getLogger(BookBeforeAdvice.class);

	public void before(Method paramMethod, Object[] paramArrayOfObject, Object paramObject) throws Throwable {

		Logger.info("before...");

	}

	public void afterReturning(Object paramObject1, Method paramMethod, Object[] paramArrayOfObject,Object paramObject2) throws Throwable {

		Logger.info("after...");

	}

}

配置文件：

<bean id="bookBefore" class="com.interceptor.BookBeforeAdvice"/>

<bean id="regexpMethodPointcutAdvisor1" class="org.springframework.aop.support.RegexpMethodPointcutAdvisor"> 

	<property name="advice" ref="bookBefore"/> 

	<property name="patterns" value=".*BookList"> 

	</property>

</bean>

<bean  class="org.springframework.aop.framework.autoproxy.DefaultAdvisorAutoProxyCreator"/>

或

<bean id="bookBefore" class="com.interceptor.BookBeforeAdvice"/>

<bean id="regexpMethodPointcutAdvisor1" class="org.springframework.aop.support.RegexpMethodPointcutAdvisor"> 

	<property name="advice" ref="bookBefore"/> 

	<property name="patterns"> 

		<list> 

			<value>com.book.control.TBookController.queryBookList</value> 

		</list> 

	</property>

</bean>

<bean  class="org.springframework.aop.framework.autoproxy.DefaultAdvisorAutoProxyCreator"/>