public ExternalProject(File file,Iterable<String> natureIds,Iterable<String> builderIds){
  super(new Path(file.getAbsolutePath()),null);
  checkState(file.isDirectory(),"Resource '" + file + "' is not a directory but a file.");
  this.file=file;
  this.natureIds=newHashSet(natureIds);
  this.builderIds=newHashSet(builderIds);
}

public ExternalProject ( File file , Iterable < String > natureIds , Iterable < String > builderIds ) { super ( new Path ( file . getAbsolutePath ( ) ) , null ) ; checkState ( file . isDirectory ( ) , "Resource '" + file + "' is not a directory but a file." ) ; this . file = file ; this . natureIds = newHashSet ( natureIds ) ; this . builderIds = newHashSet ( builderIds ) ; }
creates a new external project with the underlying wrapped file resource and the project nature and builder ids .
