ExampleFilter.java 文件源码

/**
    * Time the processing that is performed by all subsequent filters in the
    * current filter stack, including the ultimately invoked servlet.
    *
    * @param request The servlet request we are processing
    * @param result The servlet response we are creating
    * @param chain The filter chain we are processing
    *
    * @exception IOException if an input/output error occurs
    * @exception ServletException if a servlet error occurs
    */
   public void doFilter(ServletRequest request, ServletResponse response,
                        FilterChain chain)
throws IOException, ServletException {

// Store ourselves as a request attribute (if requested)
if (attribute != null)
    request.setAttribute(attribute, this);

// Time and log the subsequent processing
long startTime = System.currentTimeMillis();
       chain.doFilter(request, response);
long stopTime = System.currentTimeMillis();
filterConfig.getServletContext().log
    (this.toString() + ": " + (stopTime - startTime) +
     " milliseconds");

   }