### Question:
StringUtils { public static String implode(String delimiter, String[] strings) { if (strings.length == 0) { return ""; } else { StringBuilder sb = new StringBuilder(strings[0]); for (int i = 1; i < strings.length; i++) { sb.append(delimiter).append(strings[i]); } return sb.toString(); } } private  StringUtils(); static String implode(String delimiter, String[] strings); static String fieldNameToPath(String fieldName); static boolean isEmpty(String string);  }### Answer:
@Test public void implodeTest() throws Exception { assertEquals("a.b.c", StringUtils.implode(".", new String[]{"a", "b", "c"})); }