springmvc
@RequestParm(value = "hi",required = false) int hi,
当没有传递参数时，springmvc 初始化 将不能初始化hi为null,就进不去后端controller中的方法。解决办法，可以改成@RequestParm(value = "hi",required = false，defaultValue = "0") int hi, 或者改成
@RequestParm(value = "hi",required = false) Integer hi
