loginfilter.java

权限组件的java代码写法例子下载

package com.parddu.crm.web.filter;

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.http.HttpServletRequest;

import com.parddu.crm.util.MyFinal;

/**
 * 验证是否登陆
 * @author student
 *
 */
public class LoginFilter implements Filter {

	public void destroy() {
		// TODO Auto-generated method stub
		
	}

	public void doFilter(ServletRequest request, ServletResponse response,
			FilterChain arg2) throws IOException, ServletException {
		//从session中取得用户登录的对象
		Object obj = ((HttpServletRequest)request).getSession().getAttribute(MyFinal.SESSION_LOGIN_USERINFO);
		if(obj !=null){
			//用于已经登陆
			arg2.doFilter(request, response);
		}
		else{
			//用户没有登陆
			((HttpServletRequest)request).setAttribute(MyFinal.REQUEST_ERROR_MESSAGE, "对不起，因为你没有登陆，所以没有此访问权限。");
			((HttpServletRequest)request).getRequestDispatcher("/common/error.jsp").forward(request, response);
		}
	}

	public void init(FilterConfig arg0) throws ServletException {
		// TODO Auto-generated method stub
		
	}

}