### Question:
StringSimpleFieldActions implements AtlasFieldAction { @AtlasActionProcessor public static String capitalize(Capitalize action, String input) { if (input == null || input.length() == 0) { return input; } if (input.length() == 1) { return String.valueOf(input.charAt(0)).toUpperCase(); } return String.valueOf(input.charAt(0)).toUpperCase() + input.substring(1); }  @AtlasActionProcessor static String capitalize(Capitalize action, String input); @AtlasActionProcessor static String fileExtension(FileExtension action, String input); @AtlasActionProcessor static String lowercase(Lowercase action, String input); @AtlasActionProcessor static Character lowercaseChar(LowercaseChar action, Character input); @AtlasActionProcessor static String normalize(Normalize action, String input); @AtlasActionProcessor static String removeFileExtension(RemoveFileExtension action, String input); @AtlasActionProcessor static String separateByDash(SeparateByDash action, String input); @AtlasActionProcessor static String separateByUnderscore(SeparateByUnderscore action, String input); @AtlasActionProcessor static String trim(Trim action, String input); @AtlasActionProcessor static String trimLeft(TrimLeft action, String input); @AtlasActionProcessor static String trimRight(TrimRight action, String input); @AtlasActionProcessor static String uppercase(Uppercase action, String input); @AtlasActionProcessor static Character uppercaseChar(UppercaseChar action, Character input); static final String STRING_SEPARATOR_REGEX; static final Pattern STRING_SEPARATOR_PATTERN; }### Answer:
@Test public void testCapitalize() { assertNull(StringSimpleFieldActions.capitalize(new Capitalize(), null)); assertEquals("", StringSimpleFieldActions.capitalize(new Capitalize(), "")); assertEquals(" foo ", StringSimpleFieldActions.capitalize(new Capitalize(), " foo ")); assertEquals(" Foo", StringSimpleFieldActions.capitalize(new Capitalize(), " Foo")); assertEquals("FOo ", StringSimpleFieldActions.capitalize(new Capitalize(), "fOo ")); assertEquals(" foO ", StringSimpleFieldActions.capitalize(new Capitalize(), " foO ")); assertEquals("\t\n FOO", StringSimpleFieldActions.capitalize(new Capitalize(), "\t\n FOO")); assertEquals("\t\n FOO\f\r", StringSimpleFieldActions.capitalize(new Capitalize(), "\t\n FOO\f\r")); }