### Question:
HtmlUtil { public static String combineValues(Collection<String> values) { if (values == null || values.size() == 0) { return ""; } else { StringBuilder builder = new StringBuilder(values.size() * 30); for (String value : values) { builder.append(value).append(FIELD_DELIMITER_STRING); } return encode(builder.toString()); } }  static String encode(String fragment); static String combineValues(Collection<String> values); static Collection<String> splitValues(String value);  }### Answer:
@Test(groups = "fast") public void testJoinWithNoStrings() throws Exception { String combined = HtmlUtil.combineValues(null); Assert.assertEquals(combined, ""); combined = HtmlUtil.combineValues(new HashSet<String>()); Assert.assertEquals(combined, ""); }