1 右键无法创建，找不到scala class
https://blog.csdn.net/u011513853/article/details/52896230
2 缩进
https://jingyan.baidu.com/article/148a1921cbaaf04d71c3b1ee.html
3
【intellij idea】汇总
原文：https://www.cnblogs.com/chengdabelief/p/9244758.html
