private static int buildLeavesSet(final String filePath) throws IOException{
		File leavesFile = new File(filePath);
		FileReader leavesFileReader = new FileReader(leavesFile);
		BufferedReader br = new BufferedReader(leavesFileReader);
		int count = 0;
		String line;
		while((line = br.readLine()) != null){
			count++;
			leavesSet.add(line);
		}
		br.close();
		return count;
	}