* by multiple concurrent threads.
 *
 * @param <K> the type of the cache's keys, which are not permitted to be null
 * @param <V> the type of the cache's values, which are not permitted to be null
 * @author Charles Fry
 * @since 10.0
 */
@DoNotMock("Use CacheBuilder.newBuilder().build()")
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface Cache<K, V> {

  /**

things you should know about contributing:

1.  API changes require discussion, use cases, etc. Code comes later.
2.  Pull requests are great for small fixes for bugs, documentation, etc.
3.  Pull requests are not merged directly into the master branch.
4.  Code contributions require signing a Google CLA.

API changes
-----------

We make changes to Guava's public [APIs][], including adding new APIs, very

   *
   * <p>Changes to the returned collection will update the underlying multimap, and vice versa.
   * However, <i>adding</i> to the returned collection is not possible.
   */
  Collection<V> values();

  /**
   * Returns a view collection of all key-value pairs contained in this multimap, as {@link Entry}
   * instances.
   *

  /**
   * Returns a view of this multiset restricted to the elements less than {@code upperBound},
   * optionally including {@code upperBound} itself. The returned multiset is a view of this
   * multiset, so changes to one will be reflected in the other. The returned multiset supports all
   * operations that this multiset supports.
   *
   * <p>The returned multiset will throw an {@link IllegalArgumentException} on attempts to add

  }

  // Following Javadoc copied from Multimap and SortedSetMultimap.

  /**
   * Returns a collection view of all values associated with a key. If no mappings in the multimap
   * have the provided key, an empty collection is returned.
   *
   * <p>Changes to the returned collection will update the underlying multimap, and vice versa.
   *
   * <p>Because a {@code SortedSetMultimap} has unique sorted values for a given key, this method

  }

  // Following Javadoc copied from Multimap and SortedSetMultimap.

  /**
   * Returns a collection view of all values associated with a key. If no mappings in the multimap
   * have the provided key, an empty collection is returned.
   *
   * <p>Changes to the returned collection will update the underlying multimap, and vice versa.
   *
   * <p>Because a {@code SortedSetMultimap} has unique sorted values for a given key, this method

 * the License.
 */

package com.google.common.cache;

import com.google.common.annotations.GwtCompatible;

/**
 * Calculates the weights of cache entries.
 *
 * @author Charles Fry
 * @since 11.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface Weigher<K, V> {

  /**
   * Returns the weight of a cache entry. There is no unit for entry weights; rather they are simply

import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * LocalCache emulation for GWT.
 *
 * @param <K> the base key type
 * @param <V> the base value type
 * @author Charles Fry
 * @author Jon Donovan
 */
public class LocalCache<K, V> implements ConcurrentMap<K, V> {
  private static final int UNSET_INT = CacheBuilder.UNSET_INT;

@SuppressWarnings("rawtypes") // maybe avoidable if we rework the whole package?
@GwtCompatible
public enum MultisetFeature implements Feature<Multiset> {
  /**
   * Indicates that elements from {@code Multiset.entrySet()} update to reflect changes in the
   * backing multiset.
   */
  ENTRIES_ARE_VIEWS;

  @Override
  public Set<Feature<? super Multiset>> getImpliedFeatures() {
    return Collections.emptySet();
  }

   * of common.collect a second time with the results of the first compilation on the classpath. Or
   * just back this out once we stop doing that (which we'll do after our internal GWT setup
   * changes).
   */
  @Override
  public ImmutableMap<Object, Collection<Object>> asMap() {
    return super.asMap();
  }

  private Object readResolve() {
    return INSTANCE; // preserve singleton property
  }