}

  /** Returns a joiner which automatically places {@code separator} between consecutive elements. */
  public static Joiner on(char separator) {
    return new Joiner(String.valueOf(separator));
  }

  private final String separator;

  private Joiner(String separator) {
    this.separator = checkNotNull(separator);
  }

  private Joiner(Joiner prototype) {
    this.separator = prototype.separator;
  }

porter.png...

porter-banner.png...

.order-sm-5 {\n    -ms-flex-order: 5;\n    order: 5;\n  }\n  .order-sm-6 {\n    -ms-flex-order: 6;\n    order: 6;\n  }\n  .order-sm-7 {\n    -ms-flex-order: 7;\n    order: 7;\n  }\n  .order-sm-8 {\n    -ms-flex-order: 8;\n    order: 8;\n  }\n  .order-sm-9 {\n    -ms-flex-order: 9;\n    order: 9;\n  }\n  .order-sm-10 {\n    -ms-flex-order: 10;\n    order: 10;\n  }\n  .order-sm-11 {\n    -ms-flex-order: 11;\n    order: 11;\n  }\n  .order-sm-12 {\n    -ms-flex-order: 12;\n    order: 12;\n  }\n  .offset-sm-0...

col-12{-ms-flex:0 0 100%;flex:0 0 100%;max-width:100%}.order-first{-ms-flex-order:-1;order:-1}.order-last{-ms-flex-order:13;order:13}.order-0{-ms-flex-order:0;order:0}.order-1{-ms-flex-order:1;order:1}.order-2{-ms-flex-order:2;order:2}.order-3{-ms-flex-order:3;order:3}.order-4{-ms-flex-order:4;order:4}.order-5{-ms-flex-order:5;order:5}.order-6{-ms-flex-order:6;order:6}.order-7{-ms-flex-order:7;order:7}.order-8{-ms-flex-order:8;order:8}.order-9{-ms-flex-order:9;order:9}.order-10{-ms-flex-order:10...

  }

  private static void checkNoOutput(Joiner joiner, Iterable<Integer> set) {
    assertEquals("", joiner.join(set));
    assertEquals("", joiner.join(set.iterator()));

    Object[] array = newArrayList(set).toArray(new Integer[0]);
    assertEquals("", joiner.join(array));

    StringBuilder sb1FromIterable = new StringBuilder();
    assertSame(sb1FromIterable, joiner.appendTo(sb1FromIterable, set));

  }

  private static void checkNoOutput(Joiner joiner, Iterable<Integer> set) {
    assertEquals("", joiner.join(set));
    assertEquals("", joiner.join(set.iterator()));

    Object[] array = newArrayList(set).toArray(new Integer[0]);
    assertEquals("", joiner.join(array));

    StringBuilder sb1FromIterable = new StringBuilder();
    assertSame(sb1FromIterable, joiner.appendTo(sb1FromIterable, set));

.order-sm-5 {\n    -ms-flex-order: 5;\n    order: 5;\n  }\n  .order-sm-6 {\n    -ms-flex-order: 6;\n    order: 6;\n  }\n  .order-sm-7 {\n    -ms-flex-order: 7;\n    order: 7;\n  }\n  .order-sm-8 {\n    -ms-flex-order: 8;\n    order: 8;\n  }\n  .order-sm-9 {\n    -ms-flex-order: 9;\n    order: 9;\n  }\n  .order-sm-10 {\n    -ms-flex-order: 10;\n    order: 10;\n  }\n  .order-sm-11 {\n    -ms-flex-order: 11;\n    order: 11;\n  }\n  .order-sm-12 {\n    -ms-flex-order: 12;\n    order: 12;\n  }\n  .offset-sm-0...

  }

  private static final Joiner JOINER = Joiner.on(", ");

  @Override
  protected void assertMoreInvariants(Map<K, V> map) {
    // TODO: can these be moved to MapInterfaceTest?
    for (Entry<K, V> entry : map.entrySet()) {
      assertEquals(entry.getKey() + "=" + entry.getValue(), entry.toString());
    }

    assertEquals("{" + JOINER.join(map.entrySet()) + "}", map.toString());

      assertEquals(entry.getKey(), bimap.inverse().get(entry.getValue()));
    }

    assertEquals("{" + JOINER.join(map.entrySet()) + "}", map.toString());
    assertEquals("[" + JOINER.join(map.entrySet()) + "]", map.entrySet().toString());
    assertEquals("[" + JOINER.join(map.keySet()) + "]", map.keySet().toString());
    assertEquals("[" + JOINER.join(map.values()) + "]", map.values().toString());