Maven子项目无法读取父POM属性报错，求spring.boot.version获取方法

问题背景 #

我有一个子项目的pom.xml，其中尝试引用定义在父POM中的spring.boot.version属性：

<?xml version="1.0" encoding="UTF-8"?>
<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/xsd/maven-4.0.0.xsd">

    <modelVersion>4.0.0</modelVersion>

    <parent>
        <groupId>com.seurop.eca.ocb.middyweb.mackoffice.server</groupId>
        <artifactId>ocb-kw-mackoffice-server</artifactId>
        <version>6.0.0</version>
        <relativePath>../../pom.xml</relativePath>
    </parent>

    <artifactId>ocb-kw-mackoffice-server-annotations</artifactId>
    <name>ocb-kw-mackoffice-server-annotations</name>

    <!-- Properties Section -->
    <properties>
        <parent.version>6.0.0</parent.version>
        <eclipselink.version>2.7.12</eclipselink.version>
        <lombok.version>1.18.22</lombok.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <version>${spring.boot.version}</version>
        </dependency>
...

</project>

运行时触发错误：

org.springframework.boot:spring-boot-starter-data-jpa:jar:${spring.boot.version} was not found in...

父POM核心内容如下：

<?xml version="1.0" encoding="UTF-8"?>
<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>

    <groupId>com.seurop.eca.ocb.middyweb.mackoffice.server</groupId>
    <artifactId>ocb-kw-mackoffice-server</artifactId>
    <version>6.0.0</version>
    <name>huti</name>
  
    <packaging>pom</packaging>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.7.18</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <spring-boot.version>2.7.18</spring-boot.version>
        <activiti.version>6.0.0</activiti.version>
        <commons-csv.version>1.12.0</commons-csv.version>
        <eclipselink.version>4.0.4</eclipselink.version>
        <h2.version>2.1.210</h2.version>
        <jackson.version>2.16.1</jackson.version>
        <java.version>1.8</java.version>
        <javax.mail.version>1.4.7</javax.mail.version>
        <jasperreports-functions.version>6.19.1</jasperreports-functions.version>
        <jasperreports.version>6.19.1</jasperreports.version>
        <junit-jupiter-engine.version>5.2.0</junit-jupiter-engine.version>
        <lombok.version>1.18.34</lombok.version>
        <maven-surefire-plugin.version>2.21.0</maven-surefire-plugin.version>
        <oracle.version>11.2.0.4</oracle.version>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <spring-test-dbunit.version>1.3.0</spring-test-dbunit.version>
        <springfox.version>2.9.2</springfox.version>
        <tomcat-embed-core.version>9.0.56</tomcat-embed-core.version>
    </properties>

....
</project>

解决方案 #

方案1：修正属性名称拼写 #

父POM中定义的属性是spring-boot.version（连字符分隔），但子项目里引用的是${spring.boot.version}（点号分隔），两者名称不匹配导致无法读取。直接修改子项目的引用即可：

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
    <version>${spring-boot.version}</version>
</dependency>

方案2：利用Spring Boot Parent的依赖管理特性 #

由于父POM已经继承了spring-boot-starter-parent，这个父POM已经内置了所有Spring Boot Starter依赖的版本管理逻辑，子项目完全可以省略版本号，Maven会自动从Spring Boot Parent中匹配对应版本：

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>

这种方式不仅解决了属性引用问题，还能简化POM配置，避免手动维护版本号的麻烦。

方案3：确保父POM正确加载 #

检查子项目中<relativePath>的路径是否正确，确认Maven能找到父POM文件。如果路径无误，先执行mvn clean install将父POM安装到本地仓库，再构建子项目，避免因父POM未被识别导致的属性无法读取。

内容的提问来源于stack exchange，提问作者Nunyet Calçada