dadrus / javahome-resolver-maven-plugin

Performs the lookup of the path to the used jdk and exports it as maven property

javahome-resolver-maven-plugin

Performs the lookup of the path to the used jdk and exports it as maven property

If you have a need to develop and maintain a system and your maintenance and development branches diverge in used JDK, you could use Maven Toolchains Plugin. But what if some of your tests require the path to the JDK used to build the system, e.g. to start an application server which can't be started with a newer JDK, then this plugin may be for you.

In my specific case I use arquillian with JBoss. The corresponding arquillian container configuration expects an optional javaHome variable provided, otherwise a system wide JAVA_HOME is used. Given the situation, that the development main stream uses java 8 and JBoss EAP 6.4, but the maintenance must be performed using java 7 and JBoss EAP 6.0 (which does not support java 8), I was looking for a way not to be forced to switch between environment configurations if I just switch a branch. The idea was to use the aforementioned maven toolchains plugin. Unfortunately neither the toolchains plugin, nor the surefire, failsafe, or other toolchains aware plugins, I'm familiar with, do expose a variable pointing to a path for the choosen JDK. Thus this plugin was born.

Plugin Behaviour

• exports a javaHome property with the path to choosen JDK if maven toolchains plugin is used, otherwise
• exports a javaHome property which has the same value as the configured JAVA_HOME environment variable.

Limitations

The plugin does not integrate with eclipse properly. I was unable to find out how to force eclipse to refilter affected ressources.

Usage

You should add "javahome-resolver-maven-plugin" to your <build> configuration. The default lifecycle phase is validate. The plugin has a single goal - resolve. Here is an example:

<build>
	<plugins>
		<plugin>
			<groupId>org.apache.maven.plugins</groupId>
			<artifactId>maven-toolchains-plugin</artifactId>
			<executions>
				<execution>
					<phase>validate</phase>
					<goals>
						<goal>toolchain</goal>
					</goals>
				</execution>
			</executions>
			<configuration>
				<toolchains>
					<jdk>
						<version>${maven.compiler.target}</version>
					</jdk>
				</toolchains>
			</configuration>
		</plugin>
		<plugin>
			<groupId>eu.drus.maven.plugins</groupId>
			<artifactId>javahome-resolver-maven-plugin</artifactId>
			<executions>
				<execution>
					<goals>
						<goal>resolve</goal>
					</goals>
				</execution>
			</executions>
		</plugin>
	</plugins>
</build>