session過期 攔截器兩種處理方式返回登錄界面

========方法一========

public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object arg2) throws Exception {
    //    /EasyUI/userLogin.do
    //String uri=request.getRequestURI();        
    
    //    http://localhost:8080/EasyUI/userLogin.do
    String url=request.getRequestURL().toString();
    
    System.out.println("當前訪問地址："+url);
    
    //登錄頁面不用檢測，不然再次使用跳轉會出現Cannot forward after response has been committed錯誤（request多次提交）
    if(url.indexOf("userLogin.do")>=0){  
        return true;  
    }                  
    HttpSession session=request.getSession();
    SessionInfo sessionInfo=(SessionInfo)session.getAttribute("sessionInfo");
    
    if(sessionInfo!=null){
        return true;
    }        
    
    
     //如果判斷是 AJAX 請求,直接設置為session超時
    if( request.getHeader("x-requested-with") != null && request.getHeader("x-requested-with").equals("XMLHttpRequest")  ) {
        
         response.setHeader("sessionstatus", "timeout");  
         response.sendError(518, "session timeout.");  
         
    } else{
        //不符合條件的，跳轉到登錄界面
        request.getRequestDispatcher("/login.jsp").forward(request, response);
    }    
        
    return false;
}

　　另外在前端也是對ajax方法做處理，把代碼寫到自己的js里，在需要時引用該js

/**
 * 設置未來(全局)的AJAX請求默認選項
 * 主要設置了AJAX請求遇到Session過期的情況
 */
$.ajaxSetup({
    type: 'POST',
    complete: function(xhr,status) {
        var sessionStatus = xhr.getResponseHeader('sessionstatus');
        if(sessionStatus == 'timeout') {
            var top = getTopWinow();
            var yes = confirm('由於您長時間沒有操作, session已過期, 請重新登錄.');
            if (yes) {
                /*location.href ---如果后面沒跟值 那么就是獲取當前頁面的url
                    至於top, 表示是頂層頁面， 因為頁面之中可能嵌入了 frame 等子頁面，top表示最外面一層
                    top.location.href  -- 當前頁面地址
                 */
                top.location.href = '/EasyUI/login.jsp';            
            }else{
                window.opener=null;
                window.open('','_self');
                window.close();
            }
        }
    }
});

/**
 * 在頁面中任何嵌套層次的窗口中獲取頂層窗口
 * @return 當前頁面的頂層窗口對象
 */
function getTopWinow(){
    var p = window;
    while(p != p.parent){
        p = p.parent;
    }
    return p;
}

 

========方法二========

java輸出流，在前端彈出alert提示后跳轉，只需要在java修改

 

public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object arg2) throws Exception {
    //    /EasyUI/userLogin.do
    //String uri=request.getRequestURI();        
    
    //    http://localhost:8080/EasyUI/userLogin.do
    String url=request.getRequestURL().toString();
    
    System.out.println("當前訪問地址："+url);
    
    //登錄頁面不用檢測，不然會出現Cannot forward after response has been committed（request多次提交）
    if(url.indexOf("userLogin.do")>=0){  
        return true;  
    }  
        
    HttpSession session=request.getSession();
    SessionInfo sessionInfo=(SessionInfo)session.getAttribute("sessionInfo");
    
    if(sessionInfo!=null){
        return true;
    }
    
    toAlert(response);        
        
    return false;
}



//前台彈出alert框
public void toAlert( HttpServletResponse response){
       
    try {
         response.setContentType("text/html;charset=UTF-8");
         response.setCharacterEncoding("UTF-8");
            
         OutputStreamWriter out=new OutputStreamWriter(response.getOutputStream());   
         
         String msg="由於您長時間沒有操作，session已過期，請重新登錄！";
         msg=new String(msg.getBytes("UTF-8"));
         
         out.write("<meta http-equiv='Content-Type' content='text/html';charset='UTF-8'>");
         out.write("<script>");
         out.write("alert('"+msg+"');");
         out.write("top.location.href = '/EasyUI/login.jsp'; ");
         out.write("</script>");
         out.flush();
         out.close();

    } catch (IOException e) {
        e.printStackTrace();
    }
}