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Diffstat (limited to 'src/forkjoin/scala/concurrent/forkjoin/TransferQueue.java')
| -rw-r--r-- | src/forkjoin/scala/concurrent/forkjoin/TransferQueue.java | 133 |
1 files changed, 0 insertions, 133 deletions
diff --git a/src/forkjoin/scala/concurrent/forkjoin/TransferQueue.java b/src/forkjoin/scala/concurrent/forkjoin/TransferQueue.java deleted file mode 100644 index 7d149c7ae5..0000000000 --- a/src/forkjoin/scala/concurrent/forkjoin/TransferQueue.java +++ /dev/null @@ -1,133 +0,0 @@ -/* - * Written by Doug Lea with assistance from members of JCP JSR-166 - * Expert Group and released to the public domain, as explained at - * http://creativecommons.org/publicdomain/zero/1.0/ - */ - -package scala.concurrent.forkjoin; -import java.util.concurrent.*; - -/** - * A {@link BlockingQueue} in which producers may wait for consumers - * to receive elements. A {@code TransferQueue} may be useful for - * example in message passing applications in which producers - * sometimes (using method {@link #transfer}) await receipt of - * elements by consumers invoking {@code take} or {@code poll}, while - * at other times enqueue elements (via method {@code put}) without - * waiting for receipt. - * {@linkplain #tryTransfer(Object) Non-blocking} and - * {@linkplain #tryTransfer(Object,long,TimeUnit) time-out} versions of - * {@code tryTransfer} are also available. - * A {@code TransferQueue} may also be queried, via {@link - * #hasWaitingConsumer}, whether there are any threads waiting for - * items, which is a converse analogy to a {@code peek} operation. - * - * <p>Like other blocking queues, a {@code TransferQueue} may be - * capacity bounded. If so, an attempted transfer operation may - * initially block waiting for available space, and/or subsequently - * block waiting for reception by a consumer. Note that in a queue - * with zero capacity, such as {@link SynchronousQueue}, {@code put} - * and {@code transfer} are effectively synonymous. - * - * <p>This interface is a member of the - * <a href="{@docRoot}/../technotes/guides/collections/index.html"> - * Java Collections Framework</a>. - * - * @since 1.7 - * @author Doug Lea - * @param <E> the type of elements held in this collection - */ -public interface TransferQueue<E> extends BlockingQueue<E> { - /** - * Transfers the element to a waiting consumer immediately, if possible. - * - * <p>More precisely, transfers the specified element immediately - * if there exists a consumer already waiting to receive it (in - * {@link #take} or timed {@link #poll(long,TimeUnit) poll}), - * otherwise returning {@code false} without enqueuing the element. - * - * @param e the element to transfer - * @return {@code true} if the element was transferred, else - * {@code false} - * @throws ClassCastException if the class of the specified element - * prevents it from being added to this queue - * @throws NullPointerException if the specified element is null - * @throws IllegalArgumentException if some property of the specified - * element prevents it from being added to this queue - */ - boolean tryTransfer(E e); - - /** - * Transfers the element to a consumer, waiting if necessary to do so. - * - * <p>More precisely, transfers the specified element immediately - * if there exists a consumer already waiting to receive it (in - * {@link #take} or timed {@link #poll(long,TimeUnit) poll}), - * else waits until the element is received by a consumer. - * - * @param e the element to transfer - * @throws InterruptedException if interrupted while waiting, - * in which case the element is not left enqueued - * @throws ClassCastException if the class of the specified element - * prevents it from being added to this queue - * @throws NullPointerException if the specified element is null - * @throws IllegalArgumentException if some property of the specified - * element prevents it from being added to this queue - */ - void transfer(E e) throws InterruptedException; - - /** - * Transfers the element to a consumer if it is possible to do so - * before the timeout elapses. - * - * <p>More precisely, transfers the specified element immediately - * if there exists a consumer already waiting to receive it (in - * {@link #take} or timed {@link #poll(long,TimeUnit) poll}), - * else waits until the element is received by a consumer, - * returning {@code false} if the specified wait time elapses - * before the element can be transferred. - * - * @param e the element to transfer - * @param timeout how long to wait before giving up, in units of - * {@code unit} - * @param unit a {@code TimeUnit} determining how to interpret the - * {@code timeout} parameter - * @return {@code true} if successful, or {@code false} if - * the specified waiting time elapses before completion, - * in which case the element is not left enqueued - * @throws InterruptedException if interrupted while waiting, - * in which case the element is not left enqueued - * @throws ClassCastException if the class of the specified element - * prevents it from being added to this queue - * @throws NullPointerException if the specified element is null - * @throws IllegalArgumentException if some property of the specified - * element prevents it from being added to this queue - */ - boolean tryTransfer(E e, long timeout, TimeUnit unit) - throws InterruptedException; - - /** - * Returns {@code true} if there is at least one consumer waiting - * to receive an element via {@link #take} or - * timed {@link #poll(long,TimeUnit) poll}. - * The return value represents a momentary state of affairs. - * - * @return {@code true} if there is at least one waiting consumer - */ - boolean hasWaitingConsumer(); - - /** - * Returns an estimate of the number of consumers waiting to - * receive elements via {@link #take} or timed - * {@link #poll(long,TimeUnit) poll}. The return value is an - * approximation of a momentary state of affairs, that may be - * inaccurate if consumers have completed or given up waiting. - * The value may be useful for monitoring and heuristics, but - * not for synchronization control. Implementations of this - * method are likely to be noticeably slower than those for - * {@link #hasWaitingConsumer}. - * - * @return the number of consumers waiting to receive elements - */ - int getWaitingConsumerCount(); -} |