* See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.util.concurrent;

import static com.google.common.base.Functions.constant;
import static com.google.common.base.Functions.identity;
import static com.google.common.base.Throwables.propagateIfInstanceOf;
import static com.google.common.collect.Iterables.getOnlyElement;

        "Multiple entries with same " + conflictDescription + ": " + entry1 + " and " + entry2);
  }

  /**
   * A builder for creating immutable map instances, especially {@code public static final} maps
   * ("constant maps"). Example:
   *
   * <pre>{@code
   * static final ImmutableMap<String, Integer> WORD_TO_INT =
   *     new ImmutableMap.Builder<String, Integer>()
   *         .put("one", 1)
   *         .put("two", 2)

        // oneConstantOnly doesn't matter since it's not nullable and can be only 1 value.
        @SuppressWarnings("unused") OneConstantEnum oneConstantOnly,
        // noConstant doesn't matter since it can only be null
        @SuppressWarnings("unused") @Nullable NoConstantEnum noConstant) {
      return new GoodEquals(a, b);
    }

    // instance method ignored
    public Object badIgnored() {
      return new BadEquals();
    }

    return new Builder<>(Ordering.<K>natural().reverse());
  }

  /**
   * A builder for creating immutable sorted map instances, especially {@code public static final}
   * maps ("constant maps"). Example:
   *
   * <pre>{@code
   * static final ImmutableSortedMap<Integer, String> INT_TO_WORD =
   *     new ImmutableSortedMap.Builder<Integer, String>(Ordering.natural())
   *         .put(1, "one")

    /**
     * Returns true if a new value is currently loading, regardless of whether there is an existing
     * value. It is assumed that the return value of this method is constant for any given
     * ValueReference instance.
     */
    boolean isLoading();

    /**
     * Returns true if this reference contains an active value, meaning one that is still considered

  }

  static final class ConstantWeigher implements Weigher<Object, Object> {
    private final int constant;

    ConstantWeigher(int constant) {
      this.constant = constant;
    }

    @Override
    public int weigh(Object key, Object value) {
      return constant;
    }
  }

  static final class IntKeyWeigher implements Weigher<Integer, Object> {
    @Override

      return count.get();
    }
  }

  static final class ConstantLoader<K, V> extends CacheLoader<K, V> {
    private final V constant;

    ConstantLoader(V constant) {
      this.constant = constant;
    }

    @Override
    public V load(K key) {
      return constant;
    }
  }

  /**
   * Returns a {@code new Object()} for every request, and increments a counter for every request.

   *
   * <p><b>Java 7+ users:</b> this constant should be treated as deprecated; use {@link
   * java.nio.charset.StandardCharsets#ISO_8859_1} instead.
   *
   */
  public static final Charset ISO_8859_1 = Charset.forName("ISO-8859-1");

  /**
   * UTF-8: eight-bit UCS Transformation Format.
   *
   * <p><b>Java 7+ users:</b> this constant should be treated as deprecated; use {@link

      throw new AssertionError(impossible);
    }
  }

  /**
   * Returns an optional enum constant for the given type, using {@link Enum#valueOf}. If the
   * constant does not exist, {@link Optional#absent} is returned. A common use case is for parsing
   * user input or falling back to a default enum constant. For example, {@code
   * Enums.getIfPresent(Country.class, countryInput).or(Country.DEFAULT);}
   *
   * @since 12.0

   *                            8
   */

  // Constant matcher factory methods

  /**
   * Matches any character.
   *
   * @since 19.0 (since 1.0 as constant {@code ANY})
   */
  public static CharMatcher any() {
    return Any.INSTANCE;
  }

  /**
   * Matches no characters.
   *
   * @since 19.0 (since 1.0 as constant {@code NONE})
   */
  public static CharMatcher none() {