来源:package java.util.concurrent;
实现的接口:BlockingQueue
所以它是线程安全的。它的特点是没有内存，因为它的两个常用方法take(),put()，我们去put的时候，如果上次的put没有被take的话，那么它会被阻塞掉，直到上次的put被take掉。
代码案例：
public class SynchronousQueueExample {
static class SynchronousQueueProducer implements Runnable {
protected BlockingQueue<String> blockingQueue;
public SynchronousQueueProducer(BlockingQueue<String> queue) {
this.blockingQueue = queue;
}
@Override
public void run() {
while (true) {
try {
String data = UUID.randomUUID().toString();
System.out.println("Put: " + data);
blockingQueue.put(data);
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
static class SynchronousQueueConsumer implements Runnable {
protected BlockingQueue<String> blockingQueue;
public SynchronousQueueConsumer(BlockingQueue<String> queue) {
this.blockingQueue = queue;
}
@Override
public void run() {
while (true) {
try {
String data = blockingQueue.take();
System.out.println(Thread.currentThread().getName()
+ " take(): " + data);
Thread.sleep(2000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
public static void main(String[] args) {
final BlockingQueue<String> synchronousQueue = new SynchronousQueue<String>();
SynchronousQueueProducer queueProducer = new SynchronousQueueProducer(
synchronousQueue);
new Thread(queueProducer).start();
SynchronousQueueConsumer queueConsumer1 = new SynchronousQueueConsumer(
synchronousQueue);
new Thread(queueConsumer1).start();
SynchronousQueueConsumer queueConsumer2 = new SynchronousQueueConsumer(
synchronousQueue);
new Thread(queueConsumer2).start();
}
}
运用的场景：缓冲线程池
ExecutorService service2 = Executors.newCachedThreadPool();
--底层实现
public static ExecutorService newCachedThreadPool() {
return new ThreadPoolExecutor(0, Integer.MAX_VALUE,
60L, TimeUnit.SECONDS,
new SynchronousQueue<Runnable>())
说到这里，其他线程池都是有内存容器的，它没内存，也就不会有OOM的情况。
原文：https://www.cnblogs.com/johnzhao/p/14635095.html