logogfilter.java

一个用JSP写的网络购物系统

package cn.edu.dlnu.shop.filters;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;

import cn.edu.dlnu.frame.Constants;
import cn.edu.dlnu.frame.actions.*;
public class LogogFilter implements Filter{

	public void doFilter(ServletRequest request, ServletResponse response,
			FilterChain chain) throws IOException, ServletException {
		HttpServletRequest httpRequest=(HttpServletRequest)request;
		String requestUrl=httpRequest.getRequestURI();
		if(requestUrl.contains(".action")){
			String event="";		      
			requestUrl=requestUrl.substring(requestUrl.lastIndexOf("/")+1, requestUrl.length());
		      event=requestUrl.substring(0, requestUrl.indexOf(".action"));
		      event=event.toUpperCase();
		      System.out.print(event);
		      RequestDispatcher rd=null;
		      if(event.equals("")){
		    	  String msg="错误，请指定正确的Action";
		    	  request.setAttribute("errorMsg", msg);
		    	  rd=request.getRequestDispatcher((String) BaseAction.urls.get("DEFAULT_ERROR"));
		    	  rd.forward(request, response);
		      }else if(event.equals("LOGIN")||event.equals("REG")){
		    	  chain.doFilter(request, response);
		    	  
		      }else{
		    	  HttpSession session=httpRequest.getSession();
		    	  Object logUser=session.getAttribute(Constants.logUser);
		    	  if(logUser==null){
		    		  rd=request.getRequestDispatcher((String) BaseAction.urls.get("LOGON_PAGE"));
		    		  rd.forward(request, response);
		    	  }else{
		    		  chain.doFilter(request, response);
		    	  }
		    	  
		      }
			
		}else{
			chain.doFilter(request, response);
		}
		
	}

	public void destroy() {
		
		
	}

	public void init(FilterConfig arg0) throws ServletException {
		
		
	}

}