一、disruptor基本概念

 

二、disruptor入门程序

导入disruptor包

            
      
       com.lmax
             
      
       disruptor
             
      
       3.3.2
      
     

 

实现disruptor的四部操作

1.建立一个工厂Event类，用于创建Event类实例对象

public class OrderEvent {    private long value;    public long getValue() {        return value;    }    public void setValue(long value) {        this.value = value;    }}

public class OrderEventFactory implements EventFactory
     
       {    @Override    public OrderEvent newInstance() {        return new OrderEvent();    //这个方法就是为了返回空的数据对象Event    }}
     

 

2.创建事件监听类，用于处理数据

import com.lmax.disruptor.EventHandler;public class OrderEventHandler implements EventHandler
     
       {    @Override    public void onEvent(OrderEvent orderEvent, long l, boolean b) throws Exception {        System.out.println("消费者:"+orderEvent.getValue());    }}
     

 

3.实例化Disruptor实例，配置一系列的参数，编写Disruptory核心组件

public static void main(String[] args) {        OrderEventFactory orderEventFactory = new OrderEventFactory();        int ringBufferSize = 1024 * 1024;//指定容器的大小        ExecutorService executorService = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors()); //指定线程，建议使用自定义线程池        /**         * 1.实例化disruptor对象         * 参数一：orderEventFactory 消息（event）工厂对象         * 参数二：ringBufferSize 容器的长度         * 参数三：线程池（建议使用自定义线程池）RejectedExecutionHandler         * 参数四：ProducerType 单生产者还是多生产者         * 参数五：waitStrategy 等待策略         */        Disruptor
     
       disruptor = new Disruptor
      
       (orderEventFactory, ringBufferSize, executorService, ProducerType.SINGLE, new BlockingWaitStrategy());        //2.添加消费者的监听        disruptor.handleEventsWith(new OrderEventHandler());        //3.启动disruptor        disruptor.start();        //4.获取实际存储数据的容器： RingBuffer        RingBuffer
       
         ringBuffer = disruptor.getRingBuffer();        OrderEventProducer producer = new OrderEventProducer(ringBuffer);        ByteBuffer byteBuffer = ByteBuffer.allocate(8);        for (long i = 0; i < 100; i++) {            byteBuffer.putLong(0, i);            producer.sendData(byteBuffer);        }        disruptor.shutdown();        executorService.shutdown();    }
       
      
     

 

4.编写生产者组件，向Disruptor容器中去投递数据 （此步骤对应上述main方法中的4）

import com.lmax.disruptor.RingBuffer;import java.nio.ByteBuffer;public class OrderEventProducer {    private RingBuffer
     
       ringBuffer;    public OrderEventProducer(RingBuffer
      
        ringBuffer) {        this.ringBuffer = ringBuffer;    }    public void sendData(ByteBuffer data) {        //1 在生产者发送消息的时候，首先需要从 ringBuffer 中获取一个可用的序号        long sequence = ringBuffer.next();        try {            //2 根据这个序号找到具体的 OrderEvent 元素,草地上获取的OrderEvent对象是一个没有被赋值的空对象            OrderEvent orderEvent = ringBuffer.get(sequence);            //3 进行时间赋值处理            orderEvent.setValue(data.getLong(0));        } finally {            //4 提交操作            ringBuffer.publish(sequence);        }    }}