现在的问题是你有后方法在你的AJAX和你正在试图让它在的doGet（）你的servlet的。

The problem is you have the post method in your ajax and you are trying to get it in the doGet() of your servlet.

使用的doPost 或改变方法获取在阿贾克斯。

Use doPost or change the method to Get in your ajax.