Query on Request Dispatcher.

[Viji Elango]

In my filter code, I'm checking whether it is downtime, and if it is the case, then I'm dispatching to another JSP.
But I'm facing problems here.

1. Can I use RequestDispatcher in my Filter code?
2. Is the Usage that I've followed is correct?

   
public class MaintenanceWindowFilter implements Filter {
private FilterConfig config;
private ArrayList schedulesList = new ArrayList();
 
    
public void init(FilterConfig config) throws ServletException {
this.config = config;
}
 
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
        try {
schedulesList = (ArrayList) config.getServletContext().getAttribute("DBSchedules");
        for (count =0; count< schedulesList.size(); count++){
        ScheduleRecord schedule = new ScheduleRecord();
        schedule = (ScheduleRecord)schedulesList.get(count);
        currentTime = System.currentTimeMillis();
        startTime = schedule.getStartDate().getTime();
        endTime = schedule.getEndDate().getTime();
        if ( currentTime <= endTime && currentTime >= startTime){
        System.out.println("maintenance window,...");
        isMaintenanceWindow = true;
        config.getServletContext().getRequestDispatcher("/splashErrorPage.jsp");
        HttpServletRequest httpReq = (HttpServletRequest)request;
        HttpServletResponse httpRes = (HttpServletResponse)response; 
        dispatcher.forward(httpReq, httpRes);
        }
        }
        chain.doFilter(request,response);
        
} catch (Exception e) {
e.printStackTrace();
}

 
} 
 
public void destroy() {
this.config = null;
}
 
}

[Niranjan Deshpande]

it seems fine
just hit tomcat and run your app

[Viji Elango]

I'm getting error.
javax.servlet.ServletException
at weblogic.servlet.internal.RequestDispatcherImpl.forward(Ljavax.servle
t.ServletRequest;Ljavax.servlet.ServletResponse V(RequestDispatcherImpl.java:33
4)
at com.sgr.gss.web.filter.MaintenanceWindowFilter.doFilter(Ljavax.ser
vlet.ServletRequest;Ljavax.servlet.ServletResponse;Ljavax.servlet.FilterChain V
(MaintenanceWindowFilter.java:109)

Can't understand where I'm wrong.

[Viji Elango]

I'm getting the error, response already committed..

Any help please..

[Bachi Taurean]

Hi viji,

You cant call filterChain.doFilter after you have done a forward, since by the time you call doFilter, the request and response objects are already in control of another web component.

[Viji Elango]

Thanks for your reply..
I tried using SendRedirect.. But this time, my loop is running infinite..
Please help.

  
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
System.out.println("I'm into doFilter..");
        schedulesList.add(rec1);
        schedulesList.add(rec2);
        long currentTime, startTime, endTime;
        boolean isMaintenanceWindow = false;
        int count;
        try {
        //responseVO = (ScheduleRecordResponseVO) config.getServletContext().getAttribute("MAIN-SCHE");
        //responseVO = (ScheduleRecordResponseVO) helper.process(requestVO);
        //System.out.println("Size in Filter.." + responseVO.getSchedules().size());
        for (count =0; count< schedulesList.size(); count++){
        System.out.println("Rec ::" + count);
        ScheduleRecord schedule = new ScheduleRecord();
        schedule = (ScheduleRecord)schedulesList.get(count);
        currentTime = System.currentTimeMillis();
        startTime = schedule.getStartDate().getTime();
        endTime = schedule.getEndDate().getTime();
        if ( currentTime <= endTime && currentTime >= startTime){
        System.out.println("maintenance window,...");
        isMaintenanceWindow = true;
        HttpServletRequest httpReq = (HttpServletRequest)request;
        
        /*RequestDispatcher dispatcher = httpReq.getRequestDispatcher("/splashErrorPage.jsp");
        dispatcher.forward(httpReq, httpRes);*/
        break;
            
        }
        }
        if (isMaintenanceWindow){
        System.out.println("isMaintenanceWindow == True..");
        HttpServletResponse httpRes = (HttpServletResponse)response;
        httpRes.sendRedirect("/AccountCenter/splashErrorPage.jsp");
        httpRes.flushBuffer();
        }
        else{
        System.out.println("isMaintenanceWindow == False..");
        chain.doFilter(request,response);
        }
        
        
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

 
}