}
// add the sources from the project
for (Iterator i = this.project.getCompileSourceRoots().iterator(); i.hasNext();) {
try {
builder.addSourceTree(new File((String) i.next()));
} catch (OutOfMemoryError oome) {
// this may be the case for big sources and not enough VM mem
builder = null; // drop the builder to help GC now
// fail with some explanation