private static final HashFunction SIP_WITHOUT_KEY = Hashing.sipHash24();

  // These constants were originally ported from https://www.131002.net/siphash/siphash24.c. See:
  // https://github.com/nahi/siphash-java-inline/blob/master/src/test/java/org/jruby/util/SipHashInlineTest.java
  private static final long[] EXPECTED =
      new long[] {
        0x726fdb47dd0e0e31L,
        0x74f839c593dc67fdL,
        0x0d6c8009d9a94f5aL,
        0x85676696d7fb7e2dL,

 * Expert Group and released to the public domain, as explained at
 * http://creativecommons.org/publicdomain/zero/1.0/
 */

/*
 * Source:
 * http://gee.cs.oswego.edu/cgi-bin/viewcvs.cgi/jsr166/src/jsr166e/extra/AtomicDoubleArray.java?revision=1.5
 * (Modified to adapt to guava coding conventions and
 * to use AtomicLongArray instead of sun.misc.Unsafe)
 */

package com.google.common.util.concurrent;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.charset.Charset;
import javax.annotation.CheckForNull;

/**
 * See MurmurHash3_x86_32 in <a
 * href="https://github.com/aappleby/smhasher/blob/master/src/MurmurHash3.cpp">the C++
 * implementation</a>.
 *
 * @author Austin Appleby
 * @author Dimitris Andreou
 * @author Kurt Alfred Kluever
 */
@Immutable
@ElementTypesAreNonnullByDefault

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

/*
 * Portions of this file are modified versions of
 * http://gee.cs.oswego.edu/cgi-bin/viewcvs.cgi/jsr166/src/test/tck/AbstractExecutorServiceTest.java?revision=1.30
 * which contained the following notice:
 *
 * Written by Doug Lea with assistance from members of JCP JSR-166

public class MonitorBasedPriorityBlockingQueue<E> extends AbstractQueue<E>
    implements BlockingQueue<E> {

  // Based on revision 1.55 of PriorityBlockingQueue by Doug Lea, from
  // http://gee.cs.oswego.edu/cgi-bin/viewcvs.cgi/jsr166/src/main/java/util/concurrent/

  private static final long serialVersionUID = 5595510919245408276L;

  final PriorityQueue<E> q;
  final Monitor monitor = new Monitor(true);
  private final Monitor.Guard notEmpty =