maven's pom does not specify the package version

maven's pom does not specify the package version

The project pom specifies the dependency version

<dependency>
	<groupId>com.fasterxml.jackson.core</groupId>
	<artifactId>jackson-databind</artifactId>
</dependency>

The output dependency tree package has a specific version

<dependency>
      <groupId>com.fasterxml.jackson.core</groupId>
      <artifactId>jackson-databind</artifactId>
      <version>2.9.8</version>
      <scope>compile</scope>
    </dependency>

parent has a defined version

<parent>
    <groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-parent</artifactId>
	<version>2.1.5.RELEASE</version>
	<relativePath/> <!-- lookup parent from repository -->
	</parent>

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-dependencies</artifactId>
    <version>2.1.5.RELEASE</version>
    <relativePath>../../spring-boot-dependencies</relativePath>
  </parent>

 <properties>
    <jackson.version>2.9.8</jackson.version>
 </properties>

https://stackoverflow.com/questions/12315746/what-will-the-version-be-when-i-dont-specify-it-in-the-mavens-pom-xml/12316462#12316462
https://blog.csdn.net/kang389110772/article/details/106497338