private void parseFile(String filename) {
		int wordCount = 0;
		int numberCount = 0;

		// use character based reader as inputstream
		try (FileReader reader = new FileReader(filename);) {
			StreamTokenizer tokenizer = new StreamTokenizer(reader);
			// set constraints
			// these will ignore tokens inside comments
			tokenizer.slashSlashComments(true);
			tokenizer.slashStarComments(true);
			while (tokenizer.nextToken() != StreamTokenizer.TT_EOF) {
				if (tokenizer.ttype == StreamTokenizer.TT_WORD) {
					wordCount++;
				} else if (tokenizer.ttype == StreamTokenizer.TT_NUMBER) {
					numberCount++;
				}
				if (tokenizer.sval != null
						&& tokenizer.sval.equals("DataInputStream")) {
					System.out.println(tokenizer.toString());
				}
			}
		} catch (FileNotFoundException fe) {
			System.out.println("File not found: " + filename);
			return;
		} catch (IOException ioe) {
			System.out.println("Error parsing file");
		}
		System.out.println("Number of words: " + wordCount);
		System.out.println("Number of numerals: " + numberCount);
	}