how does the ant use in groovy - groovy

Question

this is a groovy script file MavenInit.groovy, execute in a pom.xml as follow, the var 'SCRIPTS_GROOVY' is defined in another pom.xml,what confuse me is I can not find where the "DIR_TARGET" definition, and how can use ant direct without ant = new AntBuilder()
SCRIPTS_GROOVY=project.properties['SCRIPTS_GROOVY']
ant.pathconvert(targetos:"unix", property:"DIR_TARGET") {
path(location:project.build.directory)
}
DIR_TARGET=ant.project.properties['DIR_TARGET']
project.properties.setProperty('DIR_TARGET', "${DIR_TARGET}")
project.properties.setProperty('DIR_LOGS', "${DIR_TARGET}/logs")
ant.mkdir(dir:"${DIR_TARGET}/logs")
the pom.xml excute the MavenInit.groovy as follow
<plugin>
<groupId>org.codehaus.gmavenplus</groupId>
<artifactId>gmavenplus-plugin</artifactId>
<executions>
<execution>
<id>set-maven-property</id>
<phase>initialize</phase>
<goals>
<goal>execute</goal>
</goals>
<configuration>
<scripts>
<script>file:///${SCRIPTS_GROOVY}/MavenInit.groovy</script>
</scripts>
</configuration>
</execution>
<execution>
<id>Windows-package</id>
<phase>compile</phase>
<goals>
<goal>execute</goal>
</goals>
<configuration>
<scripts>
<script>file:///${SCRIPTS_GROOVY}/PackageWindows.groovy</script>
</scripts>
</configuration>
</execution>
</executions>
</plugin>
how can I find the 'DIR_TARGET' initial defined and change the value

Answer 1

GMavenplus plugin set an ant property into its script
if (!properties.containsKey("ant")) {
try {
Object antBuilder = invokeConstructor(findConstructor(classWrangler.getClass("groovy.util.AntBuilder")));
properties.put("ant", antBuilder);
}
Also there are other properties like project, log, etc.
About DIR_TARGET, I think it is the value of project.build.directory with path separator normalized as unix like, from path(location: project.build.directory).
(I am not an ant expert, but I test on my computer and these two have same value.
Just adding the log lines to see
log.info( project.build.directory)
DIR_TARGET = ant.project.properties['DIR_TARGET']
log.info(DIR_TARGET)
I searched the ant doc and find an example from https://ant.apache.org/manual/Tasks/pathconvert.html, which verifies my guess.
<pathconvert property="prop" dirsep="|">
<map from="${basedir}/abc/" to=''/>
<path location="abc/def/ghi"/>
</pathconvert>