### Question:
ZkPath { public static String append(String... parts) { StringBuilder builder = new StringBuilder(); for (int i = 0; i < parts.length; ++i) { if (i != 0) { builder.append("/"); } builder.append(parts[i]); } return builder.toString(); }  static String append(String... parts); static String getFilename(String path); static boolean isHidden(String path); static List<String> filterOutHiddenPaths(List<String> paths);  }### Answer:
@Test public void testAppend() { assertEquals("/a/b/c", ZkPath.append("/a", "b", "c")); }