关于Disruptor的实战应用

首先，需要引入 Disruptor 的依赖库，可以在 Maven 中添加如下依赖：

<dependency>
    <groupId>com.lmax</groupId>
    <artifactId>disruptor</artifactId>
    <version>3.4.2</version>
</dependency>

接下来，定义一个 Event 类，表示要处理的任务：

@Data
public class MyEvent {
    private String message;
}

　　

然后，定义一个 EventFactory 类，用于创建 Event 对象：

public class MyEventFactory implements EventFactory<MyEvent> {
    @Override
    public MyEvent newInstance() {
        return new MyEvent();
    }
}

 

接着，定义一个 EventHandler 类，用于处理 Event 对象：

@Slf4j
public class MyEventHandler implements EventHandler<MyEvent> {
    @Override
    public void onEvent(MyEvent event, long sequence, boolean endOfBatch) {
        // 处理 event 对象的逻辑，比如打印消息
　　　　　TimeUnit.SECONDS.sleep(3);

　　　　　log.info("received message:{}, sequence:{}, endOfBatch:{}", event.getMessage(), sequence,
 endOfBatch);

 } }

 

最后，在主程序中创建 Disruptor 对象，并提交任务：

public class DisruptorMainTest {

    public static void main(String[] args) {
        Disruptor<MyEvent> disruptor = new Disruptor<>(new MyFactory(), 1024,
            Executors.defaultThreadFactory());
        disruptor.handleEventsWith(new MyEventHandler());
        disruptor.start();

        RingBuffer<MyEvent> ringBuffer = disruptor.getRingBuffer();
        for (int i = 0; i < 10; i++) {
            long sequence = ringBuffer.next();
            MyEvent event = ringBuffer.get(sequence);
            event.setMessage("Hello world " + i);
            ringBuffer.publish(sequence);
        }
        log.info("task publish finished");
        disruptor.shutdown();
        log.info("shut down");
    }
}

 

以上代码创建了一个 Disruptor 对象，并定义了一个 MyEventHandler 类来处理 Event 对象。在主程序中，首先通过调用 disruptor.start() 方法启动 Disruptor，然后通过 ringBuffer.next() 方法获取一个 Event 对象，并将要处理的数据存入该对象中。最后通过 ringBuffer.publish() 方法将 Event 对象发布到 Disruptor 中，等待处理。

注意，在程序结束时应该调用 disruptor.shutdown() 方法来关闭 Disruptor，释放资源。

Disruptor演示完毕... ...

运行结果：

20:20:26.096 [main] INFO com.hejinggang.test.first_test.service.DisruptorMainTest - task publish finished
20:20:29.099 [pool-1-thread-1] INFO com.hejinggang.test.first_test.service.handler.MyEventHandler - received message:Hello world 0, sequence:0, endOfBatch:false
20:20:32.104 [pool-1-thread-1] INFO com.hejinggang.test.first_test.service.handler.MyEventHandler - received message:Hello world 1, sequence:1, endOfBatch:false
20:20:35.105 [pool-1-thread-1] INFO com.hejinggang.test.first_test.service.handler.MyEventHandler - received message:Hello world 2, sequence:2, endOfBatch:false
20:20:38.110 [pool-1-thread-1] INFO com.hejinggang.test.first_test.service.handler.MyEventHandler - received message:Hello world 3, sequence:3, endOfBatch:false
20:20:41.114 [pool-1-thread-1] INFO com.hejinggang.test.first_test.service.handler.MyEventHandler - received message:Hello world 4, sequence:4, endOfBatch:false
20:20:44.119 [pool-1-thread-1] INFO com.hejinggang.test.first_test.service.handler.MyEventHandler - received message:Hello world 5, sequence:5, endOfBatch:false
20:20:47.120 [pool-1-thread-1] INFO com.hejinggang.test.first_test.service.handler.MyEventHandler - received message:Hello world 6, sequence:6, endOfBatch:false
20:20:50.122 [pool-1-thread-1] INFO com.hejinggang.test.first_test.service.handler.MyEventHandler - received message:Hello world 7, sequence:7, endOfBatch:false
20:20:53.126 [pool-1-thread-1] INFO com.hejinggang.test.first_test.service.handler.MyEventHandler - received message:Hello world 8, sequence:8, endOfBatch:false
20:20:56.132 [pool-1-thread-1] INFO com.hejinggang.test.first_test.service.handler.MyEventHandler - received message:Hello world 9, sequence:9, endOfBatch:true
20:20:56.132 [main] INFO com.hejinggang.test.first_test.service.DisruptorMainTest - shut down

使用到的技术：

Exectors

Disruptor

TimeUnit