MavenProject module = new MavenProject( moduleModel );
module.setFile( new File( "module-dir/pom.xml" ) );
Model parentModel = new Model();
parentModel.addModule( "../module-dir" );
MavenProject parent = new MavenProject( parentModel );
parent.setFile( new File( "parent-dir/pom.xml" ) );
String pathAdjustment = parent.getModulePathAdjustment( module );