### Question:
HostPortAuths { public static List<HostPortAuths> parse(String input) { if (input == null || input.length() == 0) return ImmutableList.of(); ImmutableList.Builder<HostPortAuths> b = ImmutableList.builder(); Iterable<String> items = Splitter.on(',').omitEmptyStrings().split(input); Splitter subsplitter = Splitter.on(':').omitEmptyStrings(); for (String i : items) { Iterable<String> subspl = subsplitter.split(i); ImmutableList<String> extracted = ImmutableList.copyOf(subspl); final int len = extracted.size(); if (len == 2 || len == 3) { String host = extracted.get(0); int port = Integer.parseInt(extracted.get(1)); Optional<String> auths = len == 3 ? Optional.of(extracted.get(2)) : Optional.empty(); b.add(new HostPortAuths(host, port, auths)); } } return b.build(); } HostPortAuths(String host, int port, Optional<String> auths);  HostPortAuths(String host, int port); String host(); int port(); HostAndPort hostAndPort(); Optional<String> auths(); StoreTool storeTool(); static List<HostPortAuths> parse(String input);  }### Answer:
@Test public void empty() { assertEquals(0, HostPortAuths.parse("").size()); }