Disruptor学习（１）

Disruptor它是一个开源的并发框架，并获得2011 Duke's 程序框架创新奖，能够在无锁的情况下实现网络的Queue并发操作。

来一个他的例子吧．绝对是ｈｅｌｌｏ　ｗｏｒｌ级别的．

只有两个类，一个是执行类，一个是自己定义的类．
自己需要定义一个event类，

package com.trevorbernard.disruptor.examples;

import com.lmax.disruptor.EventFactory;

/**
 * WARNING: This is a mutable object which will be recycled by the RingBuffer. You must take a copy of data it holds
 * before the framework recycles it.
 */
public final class ValueEvent {
    private String value;

    public String getValue() {
        return value;
    }

    public void setValue(String value) {
        this.value = value;
    }

    public final static EventFactory<ValueEvent> EVENT_FACTORY = new EventFactory<ValueEvent>() {
        public ValueEvent newInstance() {
            return new ValueEvent();
        }
    };
}

这里要用到一个ｆａｃｔｏｒｙ类，作用就是生成定义的那个类．

执行类：

package com.trevorbernard.disruptor.examples;

import java.util.UUID;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

import com.lmax.disruptor.EventHandler;
import com.lmax.disruptor.RingBuffer;
import com.lmax.disruptor.dsl.Disruptor;

public class Simple {
    @SuppressWarnings("unchecked")
    public static void main(String[] args) {
        ExecutorService exec = Executors.newCachedThreadPool();
        // Preallocate RingBuffer with 1024 ValueEvents
        Disruptor<ValueEvent> disruptor = new Disruptor<ValueEvent>(ValueEvent.EVENT_FACTORY, 1024, exec);
        final EventHandler<ValueEvent> handler = new EventHandler<ValueEvent>() {
            // event will eventually be recycled by the Disruptor after it wraps
            public void onEvent(final ValueEvent event, final long sequence, final boolean endOfBatch) throws Exception {
                System.out.println("Sequence: " + sequence+"   ValueEvent: " + event.getValue());
            }
        };

        disruptor.handleEventsWith(handler);
        RingBuffer<ValueEvent> ringBuffer = disruptor.start();
        for (long i = 10; i < 15; i++) {
            String uuid =String.valueOf(i)    ;
            long seq = ringBuffer.next();
            ValueEvent valueEvent = ringBuffer.get(seq);
            valueEvent.setValue(uuid);
            ringBuffer.publish(seq);
        }
        disruptor.shutdown();
        exec.shutdown();
    }
}

设置一个事件的监听，这里只是打印一下．
然后就是把我们定义的事件写入到RingBuffer，然后发布．负责监听的就会接受到．

整个过程是非常的简单的．
附件是源码．

评论

2 楼 zziahui 2014-05-14  

能提供个多生产多消费的demo吗？

1 楼 miebb 2014-05-07  

这个是单线程的，怎么体现并发的优势