Java如何关闭或关闭BlockingQueue？
在此示例中，您将学习如何BlockingQueue在队列中没有其他可用元素时关闭或关闭。我们将通过使生产者在“生产者－消费者”场景中发送标记对象来使用通用策略。此标记对象也称为有毒对象，将被视为队列中不再包含需要处理的对象的标志。这将使我们能够中断使用者线程的操作。
package org.nhooo.example.util.concurrent;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingQueue;
public class BlockingQueueShutdown {
public static void main(String[] args) {
BlockingQueue<String> queue = new ArrayBlockingQueue<>(32);
MyDataProducer producer = new MyDataProducer(queue);
MyDataConsumer consumer = new MyDataConsumer(queue);
new Thread(producer).start();
new Thread(consumer).start();
}
}下面是Producer将数据放入队列的对象。字符串DONE是我们的标记对象。这是最后一个数据将被放置在队列中，以供消费者提取。
package org.nhooo.example.util.concurrent;
import java.util.concurrent.BlockingQueue;
public class MyDataProducer implements Runnable {
BlockingQueue<String> queue;
public MyDataProducer(BlockingQueue<String> queue) {
this.queue = queue;
}
@Override
public void run() {
System.out.println("MyDataProducer.run");
String[] data = {"D001", "D002", "D003", "D004", "D005", "DONE"};
try {
for (String element : data) {
queue.put(element);
Thread.sleep(1000);
}
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}所述Consumer对象循环以从队列中检索的元素。当它从队列中检索标记对象时，它将中断循环并结束线程。
package org.nhooo.example.util.concurrent;
import java.util.concurrent.BlockingQueue;
public class MyDataConsumer implements Runnable {
BlockingQueue<String> queue;
public MyDataConsumer(BlockingQueue<String> queue) {
this.queue = queue;
}
@Override
public void run() {
System.out.println("MyDataConsumer.run");
while (true) {
try {
String element = queue.take();
if ("DONE".equals(element)) {
System.out.println("Exiting consumer thread, " +
"end of data reached.");
break;
}
System.out.println("Element = " + element);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}