问 Express js error handling？

var express = require('express');
var app = express();

app.use(function(err, req, res, next) {
    console.log("error!!!");
    res.send("error!!!");
});

app.get('/', function(request, response) {
    throw "some exception";
    response.send('Hello World!');
});

app.listen(5000, function() {
  console.log("Listening on 5000");
});


error:
 Express js error handling