Some knowledge of Maven Pom

Most of the entire (fan) (Yi) from the MAVEN official website of the doc Introduction to POM https://maven.apache.org/guides/introduction/introduction-to-the-pom.html

The POM (Project Obeject Model) is the most basic component unit in a MAVEN project,

1. Variables in the project variable/pom;

All elements that have only a single value can be used as variables. ${project.build.sourcedirectory}, ${project.groupid},${project.version}, the variables are prefixed with project, if they are prefixed with pom or are not prefixed at all, Do not use it because this form has been marked as obsolete (@deprecated)

Special variables (special Variables)

${project.basedir} directory where the current project is located

${project.baseuri} The directory in which the current project is located, presented as a URI and available after Maven 2.1.0

${maven.build.timestamp} timestamp represents the build start time, which is available after Maven 2.1.0-m

The ${maven.build.timestamp} timestamp can be interpreted as a specific time-date format, but the ' Maven.build.timestamp.format ' attribute is declared in the project <project> block. The code is as follows:

1 <Project>2   ...3   <Properties>4     <Maven.build.timestamp.format>Yyyy-mm-dd ' T ' HH:mm:ss ' Z '</Maven.build.timestamp.format>5   </Properties>6   ...7 </Project>

The specified format of ' Maven.build.timestamp.format ' is consistent with the format in ' Java.text.SimpleDateFormat '. If ' Maven.build.timestamp.format ' is not specified, then the default time-date format is the format of the code shown above.

You can also use the properties defined in the project as a variable. The example given by the official website Doc is to use the <properties> definition ' mavenversion ' as a variable.

1 <Project>2   ...3   <Properties>4     <mavenversion>2.1</mavenversion>5   </Properties>6   <Dependencies>7     <Dependency>8       <groupId>Org.apache.maven</groupId>9       <Artifactid>Maven-artifact</Artifactid>Ten       <version>${mavenversion}</version> One     </Dependency> A     <Dependency> -       <groupId>Org.apache.maven</groupId> -       <Artifactid>Maven-project</Artifactid> the       <version>${mavenversion}</version> -     </Dependency> -   </Dependencies> -   ... + </Project>

2. Project inheritance concept, with example;

3. Project aggregation concept, with example;

Some knowledge of Maven Pom