www.pudn.com > onlineexam.zip > CheckUserFilter.java

package org.mmxbb.exam.business; 
 
import java.io.IOException; 
import javax.servlet.FilterChain; 
import javax.servlet.FilterConfig; 
import javax.servlet.ServletException; 
import javax.servlet.ServletRequest; 
import javax.servlet.ServletResponse; 
import javax.servlet.http.HttpServlet; 
import javax.servlet.http.HttpServletRequest; 
import javax.servlet.http.HttpServletResponse; 
import javax.servlet.http.HttpSession; 
 
 
 
public class CheckUserFilter 
    extends HttpServlet 
    implements javax.servlet.Filter { 
  private FilterConfig filterConfig; 
  final String LOGIN_PAGE = "../index.jsp"; 
 
  
  public void init(FilterConfig filterConfig) throws ServletException { 
    this.filterConfig = filterConfig; 
  } 
 
  public void setFilterConfig(final FilterConfig filterConfig) { 
    this.filterConfig = filterConfig; 
  } 
 
 
  public void doFilter(ServletRequest request, ServletResponse response, 
                       FilterChain filterChain) { 
 
    HttpServletRequest hreq = (HttpServletRequest) request; 
    HttpServletResponse hres = (HttpServletResponse) response; 
    HttpSession session = hreq.getSession(); 
    if ( (session != null) && (session.getAttribute("logon") != null)) { 
      LogonBean logonBean = (LogonBean) session.getAttribute("logon"); 
      if (!logonBean.isAuthority()) { 
        try { 
          filterChain.doFilter(request, response); 
        } catch (ServletException ex) { 
          ex.printStackTrace(); 
        } catch (IOException ex) { 
          ex.printStackTrace(); 
        } 
        return; 
      } 
    } else { 
      try { 
        hres.sendRedirect(LOGIN_PAGE); 
      } catch (IOException ex1) { 
        ex1.printStackTrace(); 
      } 
    } 
  } 
 
  
  public void destroy() { 
    this.filterConfig = null; 
  } 
}