java.io.IOException: Server returned HTTP response code: 400 for URL

关于java.io.IOException: Server returned HTTP response code: 400 for URL报错和string.getBytes()字符集 - 随笔记 - 博客园
https://www.cnblogs.com/sunshineweb/p/7772222.html

URL编码问题java.io.IOException: Server returned HTTP response code: 400 for URL: http://_java_houjx3的博客-CSDN博客
https://blog.csdn.net/houjx3/article/details/84064985

java-Server returned HTTP response code: 400 for URL——CSDN问答频道
https://ask.csdn.net/questions/699824