spring mvc Controller层拦截器配置教程代码实例

痛定思痛。 2022-09-24 06:19 136阅读 0赞

原文：[spring mvc Controller层拦截器配置教程代码实例][spring mvc Controller]

源代码下载地址： [http://www.zuidaima.com/share/1825298701863936.htm][spring mvc Controller]

Controller层的拦截器继承于HandlerInterceptorAdapter

public abstract class HandlerInterceptorAdapter implements HandlerInterceptor {
          public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
             throws Exception {
    return true;
       }
    
         public void postHandle(
                 HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView)
                 throws Exception {
         }
     
         public void afterCompletion(
                HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
                 throws Exception {
         }
    
     }

Spring拦截器通过重写这三个方法实现Controller的拦截。

配置拦截器

<bean id="handlerMapping"
                class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
              <property name="interceptors">
                  <list>
                      <ref bean="controllerInterceptor" />
                  </list>
              </property>
              <property name="mappings">
                  <props>
                     <prop key="/hao/hello.do">helloWorldController</prop>
                 </props>
             </property>
         </bean>
         
         <bean id="controllerInterceptor" class="com.web.spring.mvc.interceptor.ControllerInterceptor"/>

ControllerInterceptor.java

public class ControllerInterceptor extends HandlerInterceptorAdapter {
          /**
           * 在Controller方法前进行拦截
           */
          public boolean preHandle(HttpServletRequest request,
                  HttpServletResponse response, Object handler) throws Exception {
              System.out.println("ControllerInterceptor.preHandle()");
              return true;
         }
    
         public void postHandle(HttpServletRequest request,
                 HttpServletResponse response, Object handler,
                 ModelAndView modelAndView) throws Exception {
             System.out.println("ControllerInterceptor.postHandle()");
         }
         /**
          * 在Controller方法后进行拦截
          */
         public void afterCompletion(HttpServletRequest request,
                 HttpServletResponse response, Object handler, Exception ex)
                 throws Exception {
             System.out.println("ControllerInterceptor.afterCompletion()");
         }
     }

说明：  
    发起请求,进入拦截器链，运行所有拦截器的preHandle方法，  
    1.当preHandle方法返回false时，从当前拦截器往回执行所有拦截器的afterCompletion方法，再退出拦截器链。  
    2.当preHandle方法全为true时，执行下一个拦截器,直到所有拦截器执行完。再运行被拦截的Controller。然后进入拦截器链，运行所有拦截器的postHandle方法,完后从最后一个拦截器往回执行所有拦截器的afterCompletion方法.  
    当有拦截器抛出异常时,会从当前拦截器往回执行所有拦截器的afterCompletion方法

Controller

@Controller
      @RequestMapping("/hao")
      public class HelloWorldController { 
         @RequestMapping(value = "/hello")
         public String hello(HttpServletRequest request, HttpServletResponse response) {
             System.out.println("hello");
           return "helloWorld";
         }
     }

[spring mvc Controller]: http://www.zuidaima.com/share/1825298701863936.htm