A/pom.xml:
<groupId>com.dummy.bla</groupId>
<artifactId>parent</artifactId>
<version>0.1-SNAPSHOT</version>
<packaging>pom</packaging>
B/pom.xml
<parent>
<groupId>com.dummy.bla</groupId>
<artifactId>parent</artifactId>
<version>0.1-SNAPSHOT</version>
</parent>
<groupId>com.dummy.bla.sub</groupId>
<artifactId>kid</artifactId>
B/pom.xml中需要显式注明父pom的版本号，但从MAVEN3.5之后，可以用变量表示了：
A/pom.xml:
<groupId>com.dummy.bla</groupId>
<artifactId>parent</artifactId>
<version>${revision}</version>
<packaging>pom</packaging>
<properties>
<revision>0.1-SNAPSHOT</revision>
</properties>
B/pom.xml
<parent>
<groupId>com.dummy.bla</groupId>
<artifactId>parent</artifactId>
<version>${revision}</version>
</parent>
<groupId>com.dummy.bla.sub</groupId>
<artifactId>kid</artifactId>
https://stackoverflow.com/questions/10582054/maven-project-version-inheritance-do-i-have-to-specify-the-parent-version/51969067#51969067
https://maven.apache.org/maven-ci-friendly.html