简单回答:
使用 getReader() 读取请求正文

Simple answer:
Use getReader() to read the body of the request

更多信息:
读取body中的数据有两种方法:

More info:
There are two methods for reading the data in the body:

1. getReader() 返回一个 BufferedReader 这将允许您读取请求的正文.

1. getReader() returns a BufferedReader that will allow you to read the body of the request.

getInputStream() 返回一个 ServletInputStream 如果您需要读取二进制数据.

getInputStream() returns a ServletInputStream if you need to read binary data.

文档中的注释:可以调用[任一方法] 来读取正文，而不是同时调用."

Note from the docs: "[Either method] may be called to read the body, not both."