javamaven-2code-generation

Generate a Version.java file in Maven


I have a Java project that I build using an Ant script. I am trying to convert the project to Maven.

One of the tasks generates a Java source file called Version.java that contains a static String representation of the compilation timestamp, as follows:

package com.foo.bar;
public final class Version {
 public static String VERSION="100301.1046";
}

The Ant task is very simple:

<target name="version" depends="init" description="Create Version.java">
    <echo file="src/${package.dir}/Version.java" message="package ${package.name};${line.separator}" />
    <echo file="src/${package.dir}/Version.java" append="true" message="public final class Version {${line.separator}" />
    <echo file="src/${package.dir}/Version.java"
          append="true"
          message=" public static String VERSION=&quot;${buildtime}&quot;;${line.separator}" />
    <echo file="src/${package.dir}/Version.java" append="true" message="}${line.separator}" />
    <echo message="BUILD ${buildtime}" />
</target>

Is it possible to do something similar in Maven, using generate-sources, or some other simple method?


Solution

  • After more Googling, I came up with this (in the pom.xml):

    <plugins>
      ...
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-antrun-plugin</artifactId>
        <version>1.3</version>
        <executions>
          <execution>
            <goals>
              <goal>run</goal>
            </goals>
            <phase>generate-sources</phase>
            <configuration>
              <tasks>
                <property name="src.dir" value="${project.build.sourceDirectory}" />
                <property name="package.dir" value="com/foo/bar" />
                <property name="package.name" value="com.foo.bar" />
                <property name="buildtime" value="${maven.build.timestamp}" />
    
                <echo file="${src.dir}/${package.dir}/Version.java" message="package ${package.name};${line.separator}" />
                <echo file="${src.dir}/${package.dir}/Version.java" append="true" message="public final class Version {${line.separator}" />
                <echo file="${src.dir}/${package.dir}/Version.java" append="true"
                  message=" public static String VERSION=&quot;${buildtime}&quot;;${line.separator}" />
                <echo file="${src.dir}/${package.dir}/Version.java" append="true" message="}${line.separator}" />
                <echo message="BUILD ${buildtime}" />
              </tasks>
            </configuration>
          </execution>
        </executions>
      </plugin>
      ...
    </plugins>
    

    It seems to work well and produces this Java file:

    package com.foo.bar;
    public final class Version {
     public static String VERSION="100318.1211";
    }