@Test
public void testMultiplyOnVoid() {

  final Object[][] testParameters = new Object[][] {{new StringBuilder(), "Hello", 0, ""},
      {new StringBuilder(), "Hello", 1, "Hello"},
      {new StringBuilder(), "Hello", 2, "HelloHello"}};
  StringBuilder sb = new StringBuilder();
  StringUtils.multiply(sb, null, -1);
  assertEquals("", sb.toString());
  sb = new StringBuilder();
  StringUtils.multiply(sb, null, 0);
  assertEquals("", sb.toString());
  sb = new StringBuilder();
  StringUtils.multiply(sb, null, 1);
  assertEquals("", sb.toString());
  for (final Object[] testParameter : testParameters) {
    String expected = (String) testParameter[3];
    StringBuilder buffer = (StringBuilder) testParameter[0];
    String word = (String) testParameter[1];
    int repeat = (Integer) testParameter[2];
    StringUtils.multiply(buffer, word, repeat);
    assertEquals(expected, buffer.toString());
  }
}