servlet过滤器配置白名单、黑名单

1、web.xml配置

 <filter>
         <description>过滤是否登陆</description>
         <filter-name>encodingFilter</filter-name>
         <filter-class>com.stxx.manager.filter.EncodingFilter</filter-class>
         <init-param>
             <description>配置白名单</description>
             <param-name>noCheck</param-name>
             <param-value>
                 /login.jsp,
                 /register.jsp
             </param-value>
         </init-param>
         <init-param>
             <description>过滤不成功转向地址</description>
             <param-name>redirectPath</param-name>
             <param-value>/login.jsp</param-value>
         </init-param>
     </filter>
     <filter-mapping>
         <filter-name>encodingFilter</filter-name>
         <url-pattern>*.jsp</url-pattern>
     </filter-mapping>

2、创建过滤器

 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 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 javax.servlet.http.HttpServletResponse;
 import org.apache.commons.lang.StringUtils;
 import org.apache.log4j.Logger;

 /**
  * 登陆过滤 配置白名单、黑名单
  * @author zxf
  *
  */
 public class EncodingFilter implements Filter {

     Logger log = Logger.getLogger(EncodingFilter.class);

     private static final String NO_CHECK = "noCheck";
     private static final String REDIRECT_PATH = "redirectPath";
     private List<String> noCheckList = new ArrayList<String>();
     private String redirectPath = "/login.jsp";

     public void init(FilterConfig init) throws ServletException {
         log.info("初始化filter....");
         String noChecks = init.getInitParameter(NO_CHECK);
         if(StringUtils.isNotBlank(noChecks)){
             if(StringUtils.indexOf(noChecks,",")!=-){
                 for(String no : noChecks.split(",")){
                     noCheckList.add(StringUtils.trimToEmpty(no));
                 }
             }else{
                 noCheckList.add(noChecks);
             }
         }
         String path = init.getInitParameter(REDIRECT_PATH);
         if(StringUtils.isNotBlank(path)){
             redirectPath = path;
         }
     }

     private boolean check(String path) {
         if (noCheckList == null || noCheckList.size() <= )
             return false;
         for (String s : noCheckList) {
             if (path.indexOf(s) > -) {
                 return true;
             }
         }
         return false;
     }

     public void doFilter(ServletRequest arg0, ServletResponse arg1,
             FilterChain arg2) throws IOException, ServletException {
         HttpServletRequest request = (HttpServletRequest) arg0;
         HttpServletResponse response = (HttpServletResponse) arg1;
         log.info("被filter过滤.......");
         String contextpath = request.getContextPath();
         if("/".equals(contextpath)){contextpath="";}
         if(check(request.getRequestURI())){
             log.info("白名单");
             arg2.doFilter(request, response);
         }else{
             log.info("黑名单");
             response.sendRedirect(response.encodeURL(contextpath+redirectPath));
         }
     }

     public void destroy() {
         log.info("销毁filter....");
     }

 }