------
  Using System Properties
  ------
  Allan Ramirez
  Dan Tran
  ------
  2010-01-09
  ------
  
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 ~~ NOTE: For help with the syntax of this file, see:
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Using System Properties

  There are two ways to add a list of system properties to ${thisPlugin}:

* systemPropertyVariables

  This configuration is the replacement of the deprecated <<<systemProperties>>>.  It can accept any value
  from Maven's properties that can be converted <<to String value>>.

+---+
<project>
  [...]
  <build>
    <plugins>
      <plugin>
        <groupId>${project.groupId}</groupId>
        <artifactId>${project.artifactId}</artifactId>
        <version>${project.version}</version>
        <configuration>
          <systemPropertyVariables>
            <propertyName>propertyValue</propertyName>
            <buildDirectory>\${project.build.directory}</buildDirectory>
            [...]
          </systemPropertyVariables>
        </configuration>
      </plugin>
    </plugins>
  </build>
  [...]
</project>
+---+


* systemProperties ( deprecated )

+---+
<project>
  [...]
  <build>
    <plugins>
      <plugin>
        <groupId>${project.groupId}</groupId>
        <artifactId>${project.artifactId}</artifactId>
        <version>${project.version}</version>
        <configuration>
          <systemProperties>
            <property>
              <name>propertyName</name>
              <value>propertyValue</value>
            </property>
            [...]
          </systemProperties>
        </configuration>
      </plugin>
    </plugins>
  </build>
  [...]
</project>
+---+

  Take note that only <<String valued>> properties can be passed as system
  properties. Any attempt to pass any other Maven variable type (i.e. <<<List>>>
  or a <<<URL>>> variable) will cause the variable expression to be passed
  literally (unevaluated). So having the example below:

+---+
<project>
  [...]
  <build>
    <plugins>
      <plugin>
        <groupId>${project.groupId}</groupId>
        <artifactId>${project.artifactId}</artifactId>
        <version>${project.version}</version>
        <configuration>
          <systemProperties>
            <property>
              <name>buildDir</name>
              <value>\${project.build.outputDirectory}</value>
            </property>
          </systemProperties>
        </configuration>
      </plugin>
    </plugins>
  </build>
  [...]
</project>
+---+

  will literally pass <<$\{project.build.outputDirectory\}>> because the value
  of that expression is a <<<File>>>, not a <<<String>>>.

  To inherit the "systemProperties" collection from the parent configuration,
  you will need to specify combine.children="append" on the systemProperties node in the child pom:

+---+
  <systemProperties combine.children="append">
      <property>
         [...]
      </property>
   </systemProperties>
+---+

Special VM properties

  Some system properties must be set on the command line of the forked VM, and cannot be set after the
  VM has been started. These properties must be added to the argLine parameter of the surefire plugin.

+---+
  <argLine>-Djava.endorsed.dirs=...</argLine>
+---+