@Test
public void isAlpha_shouldReturnTrue_whenStringContainsOnlyAlphaCharacters() throws Exception {

  assertEquals(true, validateTor.isAlpha("abcdEfgHiJK"));
  assertEquals(true, validateTor.isAlpha("abcd"));
  assertEquals(true, validateTor.isAlpha("A"));
  assertEquals(true, validateTor.isAlpha("Ab"));
  assertEquals(true, validateTor.isAlpha("bC"));
}