001/*
002 * Copyright (C) 2010 The Guava Authors
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package com.google.common.util.concurrent;
018
019import com.google.common.annotations.Beta;
020
021import java.util.concurrent.atomic.AtomicReference;
022import java.util.concurrent.atomic.AtomicReferenceArray;
023
024import javax.annotation.Nullable;
025
026/**
027 * Static utility methods pertaining to classes in the
028 * {@code java.util.concurrent.atomic} package.
029 *
030 * @author Kurt Alfred Kluever
031 * @since 10.0
032 */
033@Beta
034public final class Atomics {
035  private Atomics() {}
036
037  /**
038   * Creates an {@code AtomicReference} instance with no initial value.
039   *
040   * @return a new {@code AtomicReference} with no initial value
041   */
042  public static <V> AtomicReference<V> newReference() {
043    return new AtomicReference<V>();
044  }
045
046  /**
047   * Creates an {@code AtomicReference} instance with the given initial value.
048   *
049   * @param initialValue the initial value
050   * @return a new {@code AtomicReference} with the given initial value
051   */
052  public static <V> AtomicReference<V> newReference(@Nullable V initialValue) {
053    return new AtomicReference<V>(initialValue);
054  }
055
056  /**
057   * Creates an {@code AtomicReferenceArray} instance of given length.
058   *
059   * @param length the length of the array
060   * @return a new {@code AtomicReferenceArray} with the given length
061   */
062  public static <E> AtomicReferenceArray<E> newReferenceArray(int length) {
063    return new AtomicReferenceArray<E>(length);
064  }
065
066  /**
067   * Creates an {@code AtomicReferenceArray} instance with the same length as,
068   * and all elements copied from, the given array.
069   *
070   * @param array the array to copy elements from
071   * @return a new {@code AtomicReferenceArray} copied from the given array
072   */
073  public static <E> AtomicReferenceArray<E> newReferenceArray(E[] array) {
074    return new AtomicReferenceArray<E>(array);
075  }
076}