Setting properties in maven with gmaven - maven

Question

I am trying to overwrite the following property in maven using gmaven:
<build>
<plugins>
<plugin>
<groupId>org.codehaus.gmaven</groupId>
<artifactId>gmaven-plugin</artifactId>
<executions>
<execution>
<id>setproperty</id>
<phase>validate</phase>
<goals>
<goal>execute</goal>
</goals>
<configuration>
<source>
pom.properties['main.build.directory']=project.parent.build.directory.absolutePath.replace('\\','/');
</source>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
But I get this error:;
[ERROR] Failed to execute goal org.codehaus.gmaven:gmaven-plugin:1.5:execute (setproperty) on project my-project: startup failed, script139276
2592853.groovy: 1: expecting ''', found '<EOF>' # line 1, column 84.
[ERROR] 1 error
What is wrong with the above groovy snippet?

Answer 1

Value of a property which is set using gmavenplus-plugin displays correctly when accessed using the plugin. It will display correctly even if it is accessed using different instances of the same plugin.
Problem arises when value of a property which is already initialized outside the plugin is altered by the plugin and it is accessed outside the plugin. Now the value of the property is not the value as updated by plugin. The updated value is now scoped within the plugin. As a workaround to solve this issue if a property has to be updated by the plugin and is required to be accessed outside the scope of plugin: do not declare or initialize it, in case it needs to be then declare and initialize the property through the plugin.

Answer 2

I agree with #khmarbaise that this is a little weird to do, but if you must...I'm not sure offhand why it isn't working. That plugin isn't really maintained anymore. <shamelessPlug>I think this should work:
<plugin>
<groupId>org.codehaus.gmavenplus</groupId>
<artifactId>gmavenplus-plugin</artifactId>
<version>1.0</version>
<executions>
<execution>
<id>setproperty</id>
<phase>validate</phase>
<goals>
<goal>execute</goal>
</goals>
<configuration>
<scripts>
<script><![CDATA[project.properties['main.build.directory']=project.parent.build.directory.replace('\\','/')]]></script>
</scripts>
</configuration>
</execution>
</executions>
</plugin>
For more info on this mojo, check out http://groovy.github.io/GMavenPlus/execute-mojo.html.
</shamelessPlug>. However, be aware that I believe this will be scoped within the plugin.