参考：

1、https://segmentfault.com/a/1190000008659108

2、https://docs.sonarqube.org/display/DEV/Adding+Coding+Rules

3、https://docs.sonarqube.org/display/DEV/Adding+Coding+Rules+using+Java

4、https://docs.sonarqube.org/display/PLUG/Writing+Custom+Java+Rules+101

有两种方式可以扩展代码规则：但是Java只支持方式1

1、Writing coding rules using Java via a SonarQube plugin

2、Adding XPath rules directly through the SonarQube web interface

Writing coding rules in Java is a six-step process:

• Create a SonarQube plugin.
• Put a dependency on the API of the language plugin for which you are writing coding rules.
• Create as many custom rules as required
• Generate the SonarQube plugin (jar file)
• Place this jar file in the SONARQUBE_HOME/extensions/plugins directory
• Restart SonarQube server

sonar如何添加自定义JAVA规则