auth.java

《J2EE企业级应用开发》一书的配套源代码

package com.j2eeapp.filter;
import javax.servlet.FilterChain;

import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.UnavailableException;


public class Auth extends GenericFilter
{
	public void doFilter(final ServletRequest req,final ServletResponse res,FilterChain chain)throws IOException,ServletException
	{
		
		String log="";
		log=(String)filterConfig.getServletContext().getAttribute("isLog");
		if(log==new String("log")||log.equals("log") )
			chain.doFilter(req,res);
		else
			res.getOutputStream().print("please login first");
		System.out.println("Exiting auth---------");
	}
}