欧美风格网站源码,泰兴网站推广做网站,seo发展现状,wordpress的分类目录一、定义 Exchanger是一个用于线程间数据交换的工具类#xff0c;它提供一个公共点#xff0c;在这个公共点#xff0c;两个线程可以交换彼此的数据。 当一个线程调用exchange方法后将进入等待状态#xff0c;直到另外一个线程调用exchange方法#xff0c;双方完成数据交换…一、定义 Exchanger是一个用于线程间数据交换的工具类它提供一个公共点在这个公共点两个线程可以交换彼此的数据。 当一个线程调用exchange方法后将进入等待状态直到另外一个线程调用exchange方法双方完成数据交换后继续执行。 Exchanger 是 JDK 1.5 开始提供的一个用于两个工作线程之间交换数据的封装工具类简单说就是一个线程在完成一定的事务后想与另一个线程交换数据则第一个先拿出数据的线程会一直等待第二个线程直到第二个线程拿着数据到来时才能彼此交换对应数据。 从定义来看Exchanger是用于线程间进行通信、数据交换。Exchanger提供了一个同步点exchange方法两个线程调用exchange方法时无论调用时间先后两个线程会互相等到线程到达exchange方法调用点此时两个线程可以交换数据将本线程产出数据传递给对方。 /*** Waits for another thread to arrive at this exchange point (unless* the current thread is {linkplain Thread#interrupt interrupted}),* and then transfers the given object to it, receiving its object* in return.** pIf another thread is already waiting at the exchange point then* it is resumed for thread scheduling purposes and receives the object* passed in by the current thread. The current thread returns immediately,* receiving the object passed to the exchange by that other thread.** pIf no other thread is already waiting at the exchange then the* current thread is disabled for thread scheduling purposes and lies* dormant until one of two things happens:* ul* liSome other thread enters the exchange; or* liSome other thread {linkplain Thread#interrupt interrupts}* the current thread.* /ul* pIf the current thread:* ul* lihas its interrupted status set on entry to this method; or* liis {linkplain Thread#interrupt interrupted} while waiting* for the exchange,* /ul* then {link InterruptedException} is thrown and the current threads* interrupted status is cleared.** param x the object to exchange* return the object provided by the other thread* throws InterruptedException if the current thread was* interrupted while waiting*/SuppressWarnings(unchecked)public V exchange(V x) throws InterruptedException {Object v;Object item (x null) ? NULL_ITEM : x; // translate null argsif ((arena ! null ||(v slotExchange(item, false, 0L)) null) ((Thread.interrupted() || // disambiguates null return(v arenaExchange(item, false, 0L)) null)))throw new InterruptedException();return (v NULL_ITEM) ? null : (V)v;}/*** Waits for another thread to arrive at this exchange point (unless* the current thread is {linkplain Thread#interrupt interrupted} or* the specified waiting time elapses), and then transfers the given* object to it, receiving its object in return.** pIf another thread is already waiting at the exchange point then* it is resumed for thread scheduling purposes and receives the object* passed in by the current thread. The current thread returns immediately,* receiving the object passed to the exchange by that other thread.** pIf no other thread is already waiting at the exchange then the* current thread is disabled for thread scheduling purposes and lies* dormant until one of three things happens:* ul* liSome other thread enters the exchange; or* liSome other thread {linkplain Thread#interrupt interrupts}* the current thread; or* liThe specified waiting time elapses.* /ul* pIf the current thread:* ul* lihas its interrupted status set on entry to this method; or* liis {linkplain Thread#interrupt interrupted} while waiting* for the exchange,* /ul* then {link InterruptedException} is thrown and the current threads* interrupted status is cleared.** pIf the specified waiting time elapses then {link* TimeoutException} is thrown. If the time is less than or equal* to zero, the method will not wait at all.** param x the object to exchange* param timeout the maximum time to wait* param unit the time unit of the {code timeout} argument* return the object provided by the other thread* throws InterruptedException if the current thread was* interrupted while waiting* throws TimeoutException if the specified waiting time elapses* before another thread enters the exchange*/SuppressWarnings(unchecked)public V exchange(V x, long timeout, TimeUnit unit)throws InterruptedException, TimeoutException {Object v;Object item (x null) ? NULL_ITEM : x;long ns unit.toNanos(timeout);if ((arena ! null ||(v slotExchange(item, true, ns)) null) ((Thread.interrupted() ||(v arenaExchange(item, true, ns)) null)))throw new InterruptedException();if (v TIMED_OUT)throw new TimeoutException();return (v NULL_ITEM) ? null : (V)v;}V exchange(V v)等待另一个线程到达此交换点除非当前线程被中断然后将给定的对象传送给该线程并接收该线程的对象。
V exchange(V v, long timeout, TimeUnit unit)等待另一个线程到达此交换点或者当前线程被中断——抛出中断异常又或者是等候超时——抛出超时异常然后将给定的对象传送给该线程并接收该线程的对象。
