解决拦截器对ajax请求的的拦截

1、java后端代码

package com.yb.fw.app.interceptor;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import com.alibaba.fastjson.JSONObject;
import com.yb.fw.core.helper.FwConstant;
@Component
public class FrontAuthorityInterceptor implements HandlerInterceptor {
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response,
            Object handler) throws Exception {        
        String url = request.getRequestURI();
        String requestedWith =request.getHeader("X-Requested-With");
        if(url.indexOf("/store/login.do")>=0) {
            return true;
        }else if(url.indexOf("/store/land.do")>=0) {
            return true;
        }
        HttpSession session = request.getSession();
        if(session.getAttribute(FwConstant.SESSION_USERINFO) == null) {
            if("XMLHttpRequest".equals(requestedWith)){
                 System.out.println("请求被拦截,跳转到登录页面");//控制台提示用
                 JSONObject res = new JSONObject();
                 res.put("message","IsAjax");
                 response.getWriter().append(res.toString());
            }else{
            response.sendRedirect(request.getContextPath()+"/people/toLogin.do");
            }
            return false;
        }else return true;
    }
    
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response,
            Object handler, ModelAndView mv) throws Exception {
    }
    
    @Override
    public void afterCompletion(HttpServletRequest request,
            HttpServletResponse response, Object handler, Exception exception)
            throws Exception {
    }
}

（1）、判断 String XRequested =request.getHeader("X-Requested-With") 的值，目的是判断是否是ajax请求。

 （2）、组装json数据

  JSONObject res = new JSONObject();
  res.put("message","IsAjax");
  response.getWriter().append(res.toString()); 

判断的方式存在两种方式：

 (1)、

success:function(data){
    if(data.message == "IsAjax"){
        window.location.href="m-web/user/toLogin"
        return;
    }
}

（2）改jQuery源码然后在做压缩，是针对全局的方式来修改的（建议）

　if ( isSuccess ) {// if no content
                if ( status === 204 || s.type === "HEAD" ) {
                    statusText = "nocontent";

                // if not modified
                } else if ( status === 304 ) {
                    statusText = "notmodified";

                // If we have data, let's convert it
                } else {
                    statusText = response.state;
                    success = response.data;
                    error = response.error;
                    isSuccess = !error;
                    //解决ajax拦截问题
                    var result = responses.text;
                    if(result.indexOf("IsAjax")>=0){
                        window.location.href="m-web/user/toLogin";
                        return;
                    }
                }
            }