4. 程序实例
控制层：
@Controller
@RequestMapping(value = "/test")
public class TestController {
@RequestMapping(value = "/interceptor12")
public String interceptor12() {
System.out.println("Controller层方法-interceptor12");
return "index";
}
@RequestMapping(value = "/interceptor34")
public String interceptor34() {
System.out.println("Controller层方法-interceptor34");
return "index";
}
}
总共定义了5个拦截器
每个拦截器中只是打印消息，各拦截器类似，程序如下：
public class MyInterceptor1 extends HandlerInterceptorAdapter {
@Override
public boolean preHandle(HttpServletRequest request,
HttpServletResponse response, Object handler) throws Exception {
System.out.println("MyInterceptor1-preHandle()");
return true;
}
@Override
public void postHandle(HttpServletRequest request,
HttpServletResponse response, Object o, ModelAndView mav)
throws Exception {
System.out.println("MyInterceptor1-postHandle()");
}
@Override
public void afterCompletion(HttpServletRequest request,
HttpServletResponse response, Object o, Exception excptn)
throws Exception {
System.out.println("MyInterceptor1-afterCompletion()");
}
}
配置拦截器
<!-- 定义拦截器 -->
<mvc:interceptors>
<mvc:interceptor>
<!-- 拦截指定请求 -->
<mvc:mapping path="/test/interceptor12" />
<bean class="com.ll.Interceptor.MyInterceptor1" />
</mvc:interceptor>
<!-- 拦截所有的请求 -->
<mvc:interceptor>
<mvc:mapping path="/test/*" />
<bean class="com.ll.Interceptor.MyInterceptorAll" />
</mvc:interceptor>
<mvc:interceptor>
<mvc:mapping path="/test/interceptor12" />
<bean class="com.ll.Interceptor.MyInterceptor2" />
</mvc:interceptor>
<mvc:interceptor>
<mvc:mapping path="/test/interceptor34" />
<bean class="com.ll.Interceptor.MyInterceptor3" />
</mvc:interceptor>
<mvc:interceptor>
<mvc:mapping path="/test/interceptor34" />
<bean class="com.ll.Interceptor.MyInterceptor4" />
</mvc:interceptor>
</mvc:interceptors>
特别注意拦截器的配置顺序,如下：
- MyInterceptor1；
- MyInterceptorAll；
- MyInterceptor2；
- MyInterceptor3；
- MyInterceptor4；
其中，MyInterceptor1和MyInterceptor2拦截interceptor12请求，MyInterceptor3和MyInterceptor4拦截interceptor34请求，MyInterceptorAll拦截所有请求。
