基于java实现Disruptor demo

xiaozhch5 6个月前大数据

在 Java 中使用 Disruptor 实现一个简单的 Demo 主要涉及几个步骤：定义事件、创建 Disruptor 实例、定义生产者和消费者逻辑，最后启动和执行。下面是一个简单的示例：

首先，添加 Maven 依赖：

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

定义事件类

public class LongEvent {
    private long value;

    public void set(long value) {
        this.value = value;
    }

    public long get() {
        return value;
    }
}

定义生产者

import com.lmax.disruptor.RingBuffer;

public class LongEventProducer {
    private final RingBuffer<LongEvent> ringBuffer;

    public LongEventProducer(RingBuffer<LongEvent> ringBuffer) {
        this.ringBuffer = ringBuffer;
    }

    public void onData(long value) {
        long sequence = ringBuffer.next();
        try {
            LongEvent event = ringBuffer.get(sequence);
            event.set(value);
        } finally {
            ringBuffer.publish(sequence);
        }
    }
}

定义消费者

import com.lmax.disruptor.EventHandler;

public class LongEventHandler implements EventHandler<LongEvent> {
    public void onEvent(LongEvent event, long sequence, boolean endOfBatch) {
        System.out.println("Received: " + event.get());
    }
}

主程序

import com.lmax.disruptor.dsl.Disruptor;
import com.lmax.disruptor.RingBuffer;
import com.lmax.disruptor.SleepingWaitStrategy;
import java.util.concurrent.Executors;

public class Main {
    public static void main(String[] args) {
        // Executor that will be used to construct new threads for consumers
        Disruptor<LongEvent> disruptor = new Disruptor<>(
            LongEvent::new, 
            1024, 
            Executors.defaultThreadFactory(), 
            com.lmax.disruptor.dsl.ProducerType.SINGLE, 
            new SleepingWaitStrategy()
        );

        // Connect the handler
        disruptor.handleEventsWith(new LongEventHandler());

        // Start the Disruptor
        disruptor.start();

        // Get the ring buffer from the Disruptor to be used for publishing
        RingBuffer<LongEvent> ringBuffer = disruptor.getRingBuffer();

        LongEventProducer producer = new LongEventProducer(ringBuffer);

        for (long i = 0; i < 100; i++) {
            producer.onData(i);
        }

        disruptor.shutdown();
    }
}

这个示例中包含一个名为 LongEvent 的简单事件类，它只有一个 long 类型的字段。LongEventProducer 是负责生产事件的生产者类，而 LongEventHandler 则是消费者逻辑。

程序主要流程是：