assertEquals(distinct, getMultiset().elementSet().size());
  }

  @CollectionFeature.Require(absent = SUPPORTS_REMOVE)
  public void testRemove_occurrences_unsupported_absent() {
    // notice: we don't care whether it succeeds, or fails with UOE
    try {
      assertEquals(
          "multiset.remove(absent, 2) didn't return 0 or throw an exception",
          0,
          getMultiset().remove(e3(), 2));

   * message must mention two values that were associated with the duplicate key in two different
   * calls to Builder.put (though we don't really care *which* two values if there were more than
   * two). These considerations lead us to have a field of type DuplicateKey in the Builder, which
   * will remember the first duplicate key we encountered. All later calls to buildOrThrow() can

    this.allowsNullKeys = allowsNullKeys;
    this.allowsNullValues = allowsNullValues;
    this.supportsIteratorRemove = supportsIteratorRemove;
  }

  /**
   * Used by tests that require a map, but don't care whether it's populated or not.
   *
   * @return a new map instance.
   */
  protected Map<K, V> makeEitherMap() {
    try {
      return makePopulatedMap();
    } catch (UnsupportedOperationException e) {

        // subtracting two nonnegative longs can't overflow
        // cmpRemToHalfDivisor has the same sign as compare(abs(rem), abs(q) / 2).
        if (cmpRemToHalfDivisor == 0) { // exactly on the half mark
          increment = (mode == HALF_UP || (mode == HALF_EVEN && (div & 1) != 0));
        } else {
          increment = cmpRemToHalfDivisor > 0; // closer to the UP value
        }
        break;
      default:

    assertEquals(distinct, getMultiset().elementSet().size());
  }

  @CollectionFeature.Require(absent = SUPPORTS_REMOVE)
  public void testRemove_occurrences_unsupported_absent() {
    // notice: we don't care whether it succeeds, or fails with UOE
    try {
      assertEquals(
          "multiset.remove(absent, 2) didn't return 0 or throw an exception",
          0,
          getMultiset().remove(e3(), 2));

                            "b", (Collection<String>) ImmutableSortedSet.of("bob", "bagel")),
                        Helpers.mapEntry(
                            "c", (Collection<String>) ImmutableSortedSet.of("carl", "carol")),
                        Helpers.mapEntry(
                            "d", (Collection<String>) ImmutableSortedSet.of("david", "dead")),
                        Helpers.mapEntry(

        helper = new SynchronizedHelper();
      }
    }
    ATOMIC_HELPER = helper;

    // Prevent rare disastrous classloading in first call to LockSupport.park.
    // See: https://bugs.openjdk.java.net/browse/JDK-8074773
    @SuppressWarnings("unused")
    Class<?> ensureLoaded = LockSupport.class;

    this.allowsNullKeys = allowsNullKeys;
    this.allowsNullValues = allowsNullValues;
    this.supportsIteratorRemove = supportsIteratorRemove;
  }

  /**
   * Used by tests that require a map, but don't care whether it's populated or not.
   *
   * @return a new map instance.
   */
  protected Map<K, V> makeEitherMap() {
    try {
      return makePopulatedMap();
    } catch (UnsupportedOperationException e) {

    try {
      builder.buildOrThrow();
      fail("Expected exception from duplicate keys");
    } catch (IllegalArgumentException expected) {
      // We don't really care which values the exception message contains, but they should be
      // different from each other. If buildKeepingLast() collapsed duplicates, that might end up
      // not being true.

    public int available() throws IOException {
      return (int) Math.min(in.available(), left);
    }

    // it's okay to mark even if mark isn't supported, as reset won't work
    @Override
    public synchronized void mark(int readLimit) {
      in.mark(readLimit);
      mark = left;
    }

    @Override
    public int read() throws IOException {
      if (left == 0) {
        return -1;
      }