Java源码解析阻塞队列ArrayBlockingQueue功能简介

/**
 * A bounded {@linkplain BlockingQueue blocking queue} backed by an
 * array. This queue orders elements FIFO (first-in-first-out). The
 * <em>head</em> of the queue is that element that has been on the
 * queue the longest time. The <em>tail</em> of the queue is that
 * element that has been on the queue the shortest time. New elements
 * are inserted at the tail of the queue, and the queue retrieval
 * operations obtain elements at the head of the queue.
 * <p>This is a classic &quot;bounded buffer&quot;, in which a
 * fixed-sized array holds elements inserted by producers and
 * extracted by consumers. Once created, the capacity cannot be
 * changed. Attempts to {@code put} an element into a full queue
 * will result in the operation blocking; attempts to {@code take} an
 * element from an empty queue will similarly block.
 * <p>This class supports an optional fairness policy for ordering
 * waiting producer and consumer threads. By default, this ordering
 * is not guaranteed. However, a queue constructed with fairness set
 * to {@code true} grants threads access in FIFO order. Fairness
 * generally decreases throughput but reduces variability and avoids
 * starvation.
 * <p>This class and its iterator implement all of the
 * <em>optional</em> methods of the {@link Collection} and {@link
 * Iterator} interfaces.
 * <p>This class is a member of the
 * <a href="{@docRoot}/../technotes/guides/collections/index.html" rel="external nofollow" >
 * Java Collections Framework</a>.
 * @since 1.5
 * @author Doug Lea
 * @param <E> the type of elements held in this collection
 **/