目的：只是想验证一下filter对URI的过滤

流程讲解：浏览器请求URI，所有请求都走过虑器，在过滤器中处理符合某种请求的URI然后显示对应的页面内容

有2个JSP页面：

index.jsp:

    This is index page. 111111111111111111111
    
     
        
      
1111111111
        
      
2222222222
    
     
  

select.jsp:

     
     
        
      
3333333
        
      
444444444
    
     
  

filter类UrlFilter.java

public void doFilter(ServletRequest request, ServletResponse response,            FilterChain chain) throws IOException, ServletException {        HttpServletRequest httpServletRequest=(HttpServletRequest) request;        HttpServletResponse httpServletResponse=(HttpServletResponse) response;        String requestUrl = httpServletRequest.getRequestURI();        String ContextPath =httpServletRequest.getContextPath();        System.out.println(requestUrl+"========"+ContextPath);        String ContextPath1=ContextPath+"/";        String uri=requestUrl.replace(ContextPath1, "");        System.out.println("uri==========="+uri);                //String info = uri.substring(0, uri.indexOf("."));        if("index".equals(uri)){            httpServletRequest.getRequestDispatcher("index.jsp").forward(httpServletRequest, httpServletResponse);        }else if("select".equals(uri)){            httpServletRequest.getRequestDispatcher("select.jsp").forward(httpServletRequest, httpServletResponse);        }    }

web.xml配置：

     
       
         
            
       
        urlFilter
             
       
        filter.UrlFilter
         
        
            
       
        urlFilter
             
       
        /*
         
      
     

浏览器访问uri:

1、http://localhost:8080/struts/index显示index.jsp页面内容

2、http://localhost:8080/struts/select显示select.jsp页面内容