### Question:
StringHelper { public static String repeat(String a, int max) { StringBuilder sb = new StringBuilder(max + 16); for (int i=0; i<max; i++) { sb.append(a); } return sb.toString(); }  static boolean isStringEmptyOrNull(String str); static String escapeRex(String rex); static String repeat(String a, int max);  }### Answer:
@Test void testRepeat() { assertEquals("", StringHelper.repeat("A", 0)); assertEquals("Abc", StringHelper.repeat("Abc", 1)); assertEquals("AbcAbcAbc", StringHelper.repeat("Abc", 3)); }