StringUtil { public static String toLowerCase(CharSequence string) { char lowerCaseChars[] = new char[string.length()]; for (int i = 0; i < string.length(); i++) { lowerCaseChars[i] = Character.toLowerCase(string.charAt(i)); } return new String(lowerCaseChars); }  static boolean isWhitespace(char charCode); static boolean isWhitespace(int charCode); static String toLowerCase(CharSequence string); static String toUpperCase(CharSequence string); static boolean isEmpty(CharSequence theString);  }
@Test public void testToLowerCase() { assertEquals("test", StringUtil.toLowerCase("TEST")); assertEquals("simple", StringUtil.toLowerCase("SIMPLE")); }