gistfile1.java

  // The call is always made with an existing file
	public static HashMap<Character, Integer> countCharactersInFile(Path pathToFile) {
		final HashMap<Character, Integer> characterMap = new HashMap<Character, Integer>();
		try (BufferedReader reader = Files.newBufferedReader(pathToFile, Charset.defaultCharset())) {
			char c;
			while (reader.ready()) {
				c = (char) reader.read();
				if (characterMap.containsKey(c)) {
					characterMap.put(c, characterMap.get(c) + 1);
				} else {
					characterMap.put(c, 1);
				}
			}
		} catch (final IOException e) {
			e.printStackTrace();
			System.exit(-1);
		}
		return characterMap;
	}