leftvetfilter.java~2~

来自「JBuilder 2006 +SQL Server2000 +JavaBean+」· JAVA~2~ 代码 · 共 45 行

package com.pet.util;

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;

public class LeftvetFilter extends HttpServlet implements Filter {
    private FilterConfig filterConfig;
    //Handle the passed-in FilterConfig
    public void init(FilterConfig filterConfig) throws ServletException {
        this.filterConfig = filterConfig;
    }

    //Process the request/response pair
    public void doFilter(ServletRequest request, ServletResponse response,
                         FilterChain filterChain) {
        HttpServletResponse sp = (HttpServletResponse) response;
        PrintWriter out = null;
        try {
            out = sp.getWriter();
        } catch (IOException ex) {
        }
        HttpServletRequest re = (HttpServletRequest) request;
        HttpSession session = re.getSession();
        try {
            if (session.getAttribute("vetBean") != null) {
                out.println("<script type=\"text/javascript\" language=\"javascript\">alert(\"请输入用户名或密码！\");window.history.go(-1);</script>");
            }else{
                filterChain.doFilter(request, response);
            }

            filterChain.doFilter(request, response);
        } catch (ServletException sx) {
            filterConfig.getServletContext().log(sx.getMessage());
        } catch (IOException iox) {
            filterConfig.getServletContext().log(iox.getMessage());
        }
    }

    //Clean up resources
    public void destroy() {
    }
}