code: protected boolean preCompileJava(File sourceDirectory, File classDirectory, IProgressMonitor progress) {
  		assert progress != null;
  		progress.subTask(Messages.SarlBatchCompiler_51);
  		return runJavaCompiler(classDirectory, getSourcePaths(),
  				Iterables.concat(Collections.singleton(sourceDirectory), getClassPath()),
  				false, true, progress);
  	}
docs: Compile the java files before the compilation of the project's files.
  
  @param sourceDirectory the source directory where java files are stored.
  @param classDirectory the output directory, where binary files should be generated.
  @param progress monitor of the progress of the compilation.
  @return the success status. Replies <code>false</code> if the activity is canceled.