SpringMVC 拦截器<6>

servlet/filter/listener/interceptor区别与联系

1. 创建Interceptor

package com.company.combine.intercepter;

import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Created by liuqun on 2017/8/17.
 */
public class MyCustomerIntercepter1 implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o) throws Exception {
        System.out.println(getClass().getName()+"  preHandle");


        return true;
    }

    @Override
    public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {
        System.out.println(getClass().getName()+"  postHandle");
    }

    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
        System.out.println(getClass().getName()+"  afterCompletion");
    }
}

package com.company.combine.intercepter;

import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Created by liuqun on 2017/8/17.
 */
public class MyCustomerIntercepter2 implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o) throws Exception {
        System.out.println(getClass().getName()+"  preHandle");
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {
        System.out.println(getClass().getName()+"  postHandle");
    }

    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {
        System.out.println(getClass().getName()+"  afterCompletion");
    }
}

2. 在配置文件中配置：

 <mvc:interceptors>
        <mvc:interceptor>
            <mvc:mapping path="/**"/>
            <bean class="com.company.combine.intercepter.MyCustomerIntercepter1"/>
        </mvc:interceptor>
        <mvc:interceptor>
            <mvc:mapping path="/**"/>
            <bean class="com.company.combine.intercepter.MyCustomerIntercepter2"/>
        </mvc:interceptor>
    </mvc:interceptors>

3. preHandle返回false则打断拦截链直接返回，后续不再执行。返回true，则继续。
   3.1两个HandlerInterceptor的preHandle（）方法都返回true的执行结果

com.company.combine.intercepter.MyCustomerIntercepter1  preHandle
com.company.combine.intercepter.MyCustomerIntercepter2  preHandle
com.company.combine.intercepter.MyCustomerIntercepter2  postHandle
com.company.combine.intercepter.MyCustomerIntercepter1  postHandle
com.company.combine.intercepter.MyCustomerIntercepter2  afterCompletion
com.company.combine.intercepter.MyCustomerIntercepter1  afterCompletion

3.2 MyCustomerIntercepter2的preHandle返回false执行结果

com.company.combine.intercepter.MyCustomerIntercepter1  preHandle
com.company.combine.intercepter.MyCustomerIntercepter2  preHandle
com.company.combine.intercepter.MyCustomerIntercepter1  afterCompletion

3.3 两个Intercepter的preHandle都返回false执行结果

com.company.combine.intercepter.MyCustomerIntercepter1  preHandle