【Spring学习笔记-MVC-17】Spring MVC之拦截器

作者:ssslinppp      

1. 拦截器简介及应用场景




2. 拦截器接口及拦截器适配器






3. 运行流程图


正常运行


中断流程







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:
  1. MyInterceptor1;
  2. MyInterceptorAll;
  3. MyInterceptor2;
  4. MyInterceptor3;
  5. 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。







7. 其他


博客:
  淘宝-代做毕设:





附件列表

    原文地址:https://www.cnblogs.com/ssslinppp/p/4613273.html