Node.js服务器"404 not found"消息到404.html页面

我正在使用node.js,我想知道如何显示404.html而不是"404 Not Found"消息.

这是我的server.js:

var http = require("http"),
url = require("url"),
path = require("path"),
fs = require("fs")
port = process.argv[2] || 8888;

http.createServer(function(request, response) {

var uri = url.parse(request.url).pathname
, filename = path.join(process.cwd(), uri);

path.exists(filename, function(exists) {
if(!exists) {
  response.writeHead(404, {"Content-Type": "text/plain"});
  response.write("404 Not Found\n");
  response.end();
  return;
}

if (fs.statSync(filename).isDirectory()) filename += 'public/Index/index.html';

fs.readFile(filename, "binary", function(err, file) {
  if(err) {        
    response.writeHead(500, {"Content-Type": "text/plain"});
    response.write(err + "\n");
    response.end();
    return;
  }

  response.writeHead(200);
  response.write(file, "binary");
  response.end();
  });
 });
}).listen(parseInt(port, 10));

console.log("Static file server running at\n  => http://localhost:" + port + "/\nCTRL + C to shutdown");

因为你可以看到它只是一个静态文件服务器,我没有使用express.js或任何东西.