<project xmlns="http://maven.apache.org/POM/4.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>com</groupId>
        <artifactId>a</artifactId>
        <version>${revision}</version>
        <relativePath>../pom.xml</relativePath>
    </parent>
    <artifactId>b</artifactId>
    <packaging>pom</packaging>

    <properties>
        <xx>1.0</xx>
    </properties>

    <dependencies>
        <dependency>
            <groupId>com</groupId>
            <artifactId>xx</artifactId>
            <version>${revision}</version>
        </dependency>
    </dependencies>

</project>