*       that the {@linkplain ListMultimap#get collection of values} associated with a given key
 *       fulfills the {@link java.util.List} contract.
 *   <dt>{@link SetMultimap}
 *   <dd>An extension of {@link Multimap} which has order-independent equality and does not allow
 *       duplicate entries; that is, while a key may appear twice in a {@code SetMultimap}, each

    checkNotNull(executor, "Executor was null.");
    try {
      executor.execute(listener);
    } catch (Exception e) { // sneaky checked exception
      // ListenableFuture's contract is that it will not throw unchecked exceptions, so log the bad
      // runnable and/or executor and swallow it.
      log.get()
          .log(
              Level.SEVERE,

      // assumes that each set is a singleton or less (as is done for the samples)
      for (Object elem : elements) {
        @SuppressWarnings("unchecked") // safe by generator contract
        Entry<String, Collection<Integer>> entry = (Entry<String, Collection<Integer>>) elem;
        Integer value = Iterables.getOnlyElement(entry.getValue());
        builder.put(entry.getKey(), value);
      }

import java.util.Set;
import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tests representing the contract of {@link Map}. Concrete subclasses of this base class test
 * conformance of concrete {@link Map} subclasses to that contract.
 *
 * @param <K> the type of keys used by the maps under test
 * @param <V> the type of mapped values used the maps under test
 * @author George van den Driessche

      return Iterators.unmodifiableIterator(iterable.iterator());
    }

    @Override
    public String toString() {
      return iterable.toString();
    }
    // no equals and hashCode; it would break the contract!
  }

  /** Returns the number of elements in {@code iterable}. */
  public static int size(Iterable<?> iterable) {
    return (iterable instanceof Collection)
        ? ((Collection<?>) iterable).size()

 *
 * <p><b>Warning:</b> The comparison must be <i>consistent with equals</i> as explained by the
 * {@link Comparable} class specification. Otherwise, the resulting multiset will violate the {@link
 * java.util.Collection} contract, which is specified in terms of {@link Object#equals}.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#multiset">{@code Multiset}</a>.
 *

      // checking isAcquiredByCurrentThread(). For ordered locks, however, this
      // can happen because multiple locks may share the same LockGraphNode. In
      // this situation, throw an IllegalStateException as defined by contract
      // described in the documentation of WithExplicitOrdering.
      Preconditions.checkState(
          this != acquiredLock,
          "Attempted to acquire multiple locks with the same rank %s",

   * documentation.
   */
  public void add(Runnable runnable, Executor executor) {
    // Fail fast on a null. We throw NPE here because the contract of Executor states that it throws
    // NPE on null listener, so we propagate that contract up into the add method as well.
    checkNotNull(runnable, "Runnable was null.");
    checkNotNull(executor, "Executor was null.");

    mmHeap.addAll(Lists.newArrayList(1, 2, 3, 4, 47, 1, 5, 3, 0));
    assertTrue("Heap is not intact initially", mmHeap.isIntact());
    assertEquals(9, mmHeap.size());
    mmHeap.remove(5);
    assertEquals(8, mmHeap.size());
    assertTrue("Heap is not intact after remove()", mmHeap.isIntact());
    assertEquals(47, (int) mmHeap.pollLast());
    assertEquals(4, (int) mmHeap.pollLast());

    }
  }

  public void testNoNullValues() {
    for (StandardSystemProperty property : StandardSystemProperty.values()) {
      // Even though the contract in System.getProperties() specifies that a value will exist for
      // all of the listed keys, for some reason the "java.compiler" key returns null in some JVMs.
      if (property == JAVA_COMPILER) {
        continue;
      }