装了深度Linux系统v20版本后，把部分开发环境部署上了，不过在使用mvn编译java项目的时候报错

java.lang.ClassNotFoundException: javax.annotation.Generated

查看java版本是11, 于是切换至8版本

➜  ~ java -version
openjdk version "11.0.4" 2019-07-16
OpenJDK Runtime Environment (build 11.0.4+11-post-Debian-1deb10u1)
OpenJDK 64-Bit Server VM (build 11.0.4+11-post-Debian-1deb10u1, mixed mode, sharing)
➜  ~ sudo update-alternatives --config java
➜  ~ sudo update-alternatives --config javac
➜  ~ sudo update-alternatives --config jar
➜  ~ java -version
openjdk version "1.8.0_212"
OpenJDK Runtime Environment (build 1.8.0_212-8u212-b01-1~deb9u1-b01)
OpenJDK 64-Bit Server VM (build 25.212-b01, mixed mode)