private static final Splitter COMMA_SPLITTER = Splitter.on(',');

  public void testSplitNullString() {
    try {
      COMMA_SPLITTER.split(null);
      fail();
    } catch (NullPointerException expected) {
    }
  }

  public void testCharacterSimpleSplit() {
    String simple = "a,b,c";
    Iterable<String> letters = COMMA_SPLITTER.split(simple);

  private static final Splitter COMMA_SPLITTER = Splitter.on(',');

  public void testSplitNullString() {
    try {
      COMMA_SPLITTER.split(null);
      fail();
    } catch (NullPointerException expected) {
    }
  }

  public void testCharacterSimpleSplit() {
    String simple = "a,b,c";
    Iterable<String> letters = COMMA_SPLITTER.split(simple);