adminfilter.java

一个不错的bbs论坛系统．对初学者很有帮助

package com.yhbbs.admin.service;

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 com.yhbbs.user.itface.bean.UserSession;
import com.yhbbs.utils.Constants;

/**
 * <p>Title:系统管理过滤器</p>
 * <li>用来检查在用户在执行操作系统后台时,session是否失效.</li>
 * <li>如果用户没有登录或者session失效,则跳转到登录界面.</li>
 * <br><b>CopyRight: yyhweb[由由华网]</b>
 * @author stephen
 * @version YH-2.0
 */
public class AdminFilter implements Filter {
	
	protected FilterConfig filterConfig;
	
	public void destroy() {
		filterConfig = null;
	}

	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
		
		// 从session取得当前用户
		HttpSession session = ((HttpServletRequest) request).getSession();
		UserSession curUser = (UserSession) session.getAttribute(Constants.bbsuser);
		if (curUser == null || curUser.getUsertype()<7) {
			RequestDispatcher rd = request.getRequestDispatcher("/ErrorAdmin.htm");
			rd.forward(request, response);
			return;
		}
		chain.doFilter(request, response);
	}

	public void init(FilterConfig filterConfig) throws ServletException {
		this.filterConfig = filterConfig;		
	}
}