diff --git a/src/main/java/com/alibaba/druid/util/TransferQueue.java b/src/main/java/com/alibaba/druid/util/TransferQueue.java deleted file mode 100644 index 204db4306b..0000000000 --- a/src/main/java/com/alibaba/druid/util/TransferQueue.java +++ /dev/null @@ -1,165 +0,0 @@ -/* - * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - * - */ - -/* - * - * - * - * - * - * 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 com.alibaba.druid.util; - -import java.util.concurrent.BlockingQueue; -import java.util.concurrent.SynchronousQueue; -import java.util.concurrent.TimeUnit; - -/** - * 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. - * - *
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. - * - *
This interface is a member of the
- *
- * Java Collections Framework.
- *
- * @since 1.7
- * @author Doug Lea
- * @param 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.
- *
- * 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.
- *
- * 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();
-}