### Question:
Strings { public static String rightPad(String str, int size) { return rightPad(str, size, ' '); } private  Strings(); static boolean isNullOrEmpty(String str); static boolean hasText(String s); static boolean allHasText(String... strings); static boolean allNullOrEmpty(String... strings); static String leftTrim(String s); static String rightTrim(String str); static boolean containsNone(String str, String invalidCharsStr); static boolean containsOnly(String str, String allowedChars); static String repeat(char c, int count); static String repeat(String str, int count); static String reverse(String str); static String insertFromLeft(String str, int interval, String stringToInsert); static String insertFromRight(String str, int interval, String stringToInsert); static String rightPad(String str, int size); static String rightPad(String str, int size, char padChar); static String rightPad(String str, int size, String padStr); static String leftPad(String str, int size); static String leftPad(String str, int size, char padChar); static String subStringUntilFirst(String str, String s); static String subStringUntilLast(String str, String s); static String subStringAfterFirst(String str, String s); static String subStringAfterLast(String str, String s); static String leftPad(String str, int size, String padStr); static String whiteSpacesToSingleSpace(String str); static String eliminateWhiteSpaces(String str); static String[] separateGrams(String word, int gramSize); static final String EMPTY_STRING; static final String[] EMPTY_STRING_ARRAY; }### Answer:
@Test public void testRightPad_StringInt() { assertEquals(null, rightPad(null, 5)); assertEquals(" ", rightPad("", 5)); assertEquals("abc ", rightPad("abc", 5)); assertEquals("abc", rightPad("abc", 2)); assertEquals("abc", rightPad("abc", -1)); }
@Test public void testRightPad_StringIntChar() { assertEquals(null, rightPad(null, 5, ' ')); assertEquals(" ", rightPad("", 5, ' ')); assertEquals("abc ", rightPad("abc", 5, ' ')); assertEquals("abc", rightPad("abc", 2, ' ')); assertEquals("abc", rightPad("abc", -1, ' ')); assertEquals("abcxx", rightPad("abc", 5, 'x')); String str = rightPad("aaa", 10000, 'a'); assertEquals(10000, str.length()); }
@Test public void testRightPad_StringIntString() { assertEquals(null, rightPad(null, 5, "-+")); assertEquals(" ", rightPad("", 5, " ")); assertEquals(null, rightPad(null, 8, null)); assertEquals("abc-+-+", rightPad("abc", 7, "-+")); assertEquals("abc-+~", rightPad("abc", 6, "-+~")); assertEquals("abc-+", rightPad("abc", 5, "-+~")); assertEquals("abc", rightPad("abc", 2, " ")); assertEquals("abc", rightPad("abc", -1, " ")); assertEquals("abc ", rightPad("abc", 5, null)); assertEquals("abc ", rightPad("abc", 5, "")); }