package com.inteceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.log4j.Logger;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;
import org.springframework.web.servlet.HandlerInterceptor;  

public class TimeInteceptor implements HandlerInterceptor{

    private static final Logger logger = Logger.getLogger(TimeInteceptor.class);

    //before the actual handler will be executed
    public boolean preHandle(HttpServletRequest request, 
        HttpServletResponse response, Object handler)
        throws Exception {

        long startTime = System.currentTimeMillis();
        request.setAttribute("startTime", startTime);

        return true;
    }

    //after the handler is executed
    public void postHandle(
        HttpServletRequest request, HttpServletResponse response, 
        Object handler, ModelAndView modelAndView)
        throws Exception {

        long startTime = (Long)request.getAttribute("startTime");

        long endTime = System.currentTimeMillis();

        long executeTime = endTime - startTime;

        //modified the exisitng modelAndView
        modelAndView.addObject("executeTime",executeTime);

        //log it
        if(logger.isDebugEnabled()){
           logger.debug("[" + handler + "] executeTime : " + executeTime + "ms");
        }
    }

    public void afterCompletion(HttpServletRequest arg0,
            HttpServletResponse arg1, Object arg2, Exception arg3)
            throws Exception {
        // TODO Auto-generated method stub
        
    }
}