disruptor
github地址
https://github.com/LMAX-Exchange/disruptor
Disruptor是一个java的blockingqueue,它的目的是在相同处理器的不同线程之间move数据(message or event)。相对于一般的queue,Disruptor具有一些重要的特性:为事件预分配内存、可选的lock-free、根据消费依赖路径多路发送事件给消费者。
Disruptor说明文档:https://github.com/LMAX-Exchange/disruptor/wiki/Introduction
LMAX是一种新型零售金融交易平台,它能够以很低的延迟产生大量交易。这个系统是建立在JVM平台上,其核心是一个业务逻辑处理器,它能够在一个线程里每秒处理600万订单。业务逻辑处理器完全是运行在内存中,使用事件源驱动的方式。业务逻辑驱动器的核心是Disruptor。Disruptor主动将数据发送到数据消费端,600万指的是分发给消费端的订单数。
Disruptor是一个开源的并发框架,并获得2011年的程序框架创新奖,能够在无锁的情况下实现网络Queue并发操作。Disruptor是一个高性能的异步处理框架,或者认为是最快的消息框架(轻量的JMS),也可以是一个观察者模式的实现,或者事件监听模式的实现。
Disruptor相关术语:
RingBuffer:它是Disruptor最主要的组件,从3.0开始RingBuffer仅仅负责存储和更新在Disruptor中流通的数据,对一些特殊的使用场景能够被用户(使用其他数据结构)完全替代。
sequence:表示一个特殊组件处理的序号,每个消费者(EventProcessor)都维持着一个Sequence,大部分的并发代码依赖这些Sequence值运转,因此Sequence支持多种当前为AtomicLong类的特性。
Sequencer:这是Disruptor真正的核心,实现了这个接口的两种生产者(单生产者和多生产者)均实现了所有的并发算法,为了在生产者和消费者之间进行准确快速的数据传递。
SequenceBarrier:由Sequencer生成,并且包含了已经发布的Sequence的引用,它包含了决定是否有供消费者来消费的Event的逻辑。
WaitStrategy:决定一个消费者将如何等待生产者将Event置入Disruptor。
Event:从生产者到消费者过程中所处理的数据单元,它完全由用户自己定义。
eventhandler:由用户实现并且代表了Disruptor中的一个消费者的接口。
producer:由用户实现,它调用RingBuffer来插入事件,在Disruptor中没有其相应的实现代码,由用户实现。
WorkProcessor:确保每个sequence只被一个processor消费,在同一个WorkPool中处理多个WorkerProcessor不会消费同样的sequence。
WorkerPool:一个WorkProcessor池,其中WorkProcessor将消费sequence,所以任务可以在实现了WorkHandler接口的worker之间移交。
RingBuffer是一个首尾相接的环,可以把它作为在不同上下文(线程)之间传递数据的buffer。RingBuffer中拥有一个序号Sequence,它指向下一个可用元素。随着Producer不停地填充数据到这个buffer(可能也会有读取),这个序号会一直增长,直到绕过这个环。要找到数组中当前序号指向的元素,可以通过mod操作实现,即sequence mod array length = array index 。RingBuffer槽的个数最好为2的n次方,这样有利于基于二进制的计算机进行计算。RingBuffer使用的是数组的顺序存储结构,所以比链表更快。
在Disruptor中,创建一个HelloWorld示例程序的步骤:
1.建立一个Event类
2.建立一个工厂Event类,用于创建Event类实例对象
3.建立一个监听事件类,用于消费处理Event类型的数据
4.main函数测试代码编写,实例化Disruptor实例,配置一系列参数。然后,对Disruptor实例绑定监听事件类,接收并处理数据
5.在Disruptor中,真正存储数据的核心叫做RingBuffer,通过Disruptor实例获取RingBuffer,生产者Producer将数据生产出来,将数据加入到RingBuffer的槽中
LongEvent.java
public class LongEvent {
private long value;
public long getValue() {
return value;
}
public void setValue(long value) {
this.value = value;
}
}
LongEventFactory.java
// 需要让disruptor为我们创建事件,我们同时还声明了一个EventFactory来实例化Event对象。
public class LongEventFactory implements EventFactory {
@Override
public Object newinstance() {
return new LongEvent();
}
}
LongEventProducer.javaimport java.nio.ByteBuffer;
import com.lmax.disruptor.RingBuffer;
/**
* 发布事件最少需要两步:获取下一个事件槽并发布事件(发布事件的时候要使用try/finally保证事件一定会被发布)。
* 如果我们使用RingBuffer.next()获取一个事件槽,那么一定要发布对应的事件。
* 如果不能发布事件,那么就会引起Disruptor状态的混乱。
* 尤其是在多个事件生产者的情况下会导致事件消费者失速,从而不得不重启应用才能会恢复。
*/
public class LongEventProducer {
private final RingBuffer<LongEvent> ringBuffer;
public LongEventProducer(RingBuffer<LongEvent> ringBuffer){
this.ringBuffer = ringBuffer;
}
/**
* onData用来发布事件,每调用一次就发布一次事件
* 它的参数用事件传递给消费者
*/
public void onData(ByteBuffer bb){
//1.可以把ringBuffer看做一个事件队列,那么next就是得到下面一个事件槽
long sequence = ringBuffer.next();
try {
//2.用上面的索引取出一个空的事件用于填充(获取该序号对应的事件对象)
LongEvent event = ringBuffer.get(sequence);
//3.获取要通过事件传递的业务数据
event.setValue(bb.getLong(0));
} finally {
//4.发布事件
//注意,最后的 ringBuffer.publish 方法必须包含在 finally 中以确保必须得到调用;
//某个请求的 sequence 未被提交,将会堵塞后续的发布操作或者其它的 producer。
ringBuffer.publish(sequence);
}
}
}
LongEventHandler.javaimport com.lmax.disruptor.EventHandler;
//我们还需要一个事件消费者,也就是一个事件处理器。这个事件处理器简单地把事件中存储的数据打印到终端:
public class LongEventHandler implements EventHandler<LongEvent> {
@Override
public void onEvent(LongEvent longEvent, long l, boolean b) throws Exception {
System.out.println(longEvent.getValue());
}
}
LongEventMain.javaimport java.nio.ByteBuffer;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import com.lmax.disruptor.RingBuffer;
import com.lmax.disruptor.YieldingWaitStrategy;
import com.lmax.disruptor.dsl.Disruptor;
import com.lmax.disruptor.dsl.ProducerType;
public class LongEventMain {
public static void main(String[] args) throws Exception {
//创建线程池
ExecutorService executor = Executors.newcachedThreadPool();
//创建LongEvent工厂
LongEventFactory factory = new LongEventFactory();
//创建bufferSize ,也就是RingBuffer大小,必须是2的N次方
int ringBufferSize = 1024 * 1024; //
/**
//BlockingWaitStrategy 是最低效的策略,但其对cpu的消耗最小并且在各种不同部署环境中能提供更加一致的性能表现
WaitStrategy BLOCKING_WAIT = new BlockingWaitStrategy();
//SleepingWaitStrategy 的性能表现跟BlockingWaitStrategy差不多,对CPU的消耗也类似,但其对生产者线程的影响最小,适合用于异步日志类似的场景
WaitStrategy SLEEPING_WAIT = new SleepingWaitStrategy();
//YieldingWaitStrategy 的性能是最好的,适合用于低延迟的系统。在要求极高性能且事件处理线数小于CPU逻辑核心数的场景中,推荐使用此策略;例如,CPU开启超线程的特性
WaitStrategy YIELDING_WAIT = new YieldingWaitStrategy();
*/
//创建disruptor,LongEvent为指定的消费数据类型,即每个槽中存放的数据类型
Disruptor<LongEvent> disruptor =
new Disruptor<LongEvent>(factory, ringBufferSize, executor, ProducerType.SINGLE, new YieldingWaitStrategy());
// 连接消费事件方法
disruptor.handleEventsWith(new LongEventHandler());
// 启动
disruptor.start();
//获取具体存放数据的ringbuffer(环形结构)
RingBuffer<LongEvent> ringBuffer = disruptor.getRingBuffer();
LongEventProducer producer = new LongEventProducer(ringBuffer);
//LongEventProducerWithTranslator producer = new LongEventProducerWithTranslator(ringBuffer);
ByteBuffer byteBuffer = ByteBuffer.allocate(8);
for(long i = 0; i<10; i++){
byteBuffer.putLong(0, i);
producer.onData(byteBuffer);
}
disruptor.shutdown();//关闭 disruptor,方法会堵塞,直至所有的事件都得到处理;
executor.shutdown();//关闭使用的线程池;如果需要的话,必须手动关闭, disruptor在 shutdown时不会自动关闭线程池;
}
}
Eclipse的console输出在LongEventMain.java中,将代码
LongEventProducer producer = new LongEventProducer(ringBuffer);
修改为
LongEventProducerWithTranslator producer = new LongEventProducerWithTranslator(ringBuffer);
同时,将LongEventProducer.java修改为LongEventProducerWithTranslator.java
import java.nio.ByteBuffer;
import com.lmax.disruptor.EventTranslatorOneArg;
import com.lmax.disruptor.RingBuffer;
/**
* Disruptor 3.0提供了lambda式的API。这样可以把一些复杂的操作放在Ring Buffer,
* 所以在Disruptor3.0以后的版本最好使用Event Publisher或者Event Translator来发布事件
*/
public class LongEventProducerWithTranslator {
//一个translator可以看做一个事件初始化器,publicEvent方法会调用它
//填充Event
private static final EventTranslatorOneArg<LongEvent, ByteBuffer> TRANSLATOR =
new EventTranslatorOneArg<LongEvent, ByteBuffer>() {
@Override
public void translateTo(LongEvent event, long sequeue, ByteBuffer buffer) {
event.setValue(buffer.getLong(0));
}
};
private final RingBuffer<LongEvent> ringBuffer;
public LongEventProducerWithTranslator(RingBuffer<LongEvent> ringBuffer) {
this.ringBuffer = ringBuffer;
}
public void onData(ByteBuffer buffer){
ringBuffer.publishEvent(TRANSLATOR, buffer);
}
}
在Eclipse的console输出如下:直接使用RingBuffer(使用消息处理器)
Main1.java
import java.util.concurrent.Callable;
import java.util.concurrent.executionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import com.lmax.disruptor.BATchEventProcessor;
import com.lmax.disruptor.EventFactory;
import com.lmax.disruptor.EventProcessor;
import com.lmax.disruptor.RingBuffer;
import com.lmax.disruptor.SequenceBarrier;
import com.lmax.disruptor.YieldingWaitStrategy;
public class Main1 {
public static void main(String[] args) throws Exception {
int BUFFER_SIZE=1024;
int THREAD_NUMBERS=4;
/*
* createSingleProducer创建一个单生产者的RingBuffer,
* 第一个参数叫EventFactory,从名字上理解就是"事件工厂",其实它的职责就是产生数据填充RingBuffer的区块。
* 第二个参数是RingBuffer的大小,它必须是2的指数倍 目的是为了将求模运算转为&运算提高效率
* 第三个参数是RingBuffer的生产都在没有可用区块的时候(可能是消费者(或者说是事件处理器) 太慢了)的等待策略
*/
final RingBuffer<Trade> ringBuffer = RingBuffer.createSingleProducer(new EventFactory<Trade>() {
@Override
public Trade newInstance() {
return new Trade();
}
}, BUFFER_SIZE, new YieldingWaitStrategy());
//创建线程池
ExecutorService executors = Executors.newFixedThreadPool(THREAD_NUMBERS);
//创建SequenceBarrier
SequenceBarrier sequenceBarrier = ringBuffer.newBarrier();
//创建消息处理器
BatchEventProcessor<Trade> transProcessor = new BatchEventProcessor<Trade>(
ringBuffer, sequenceBarrier, new TradeHandler());
//这一步的目的就是把消费者的位置信息引用注入到生产者 如果只有一个消费者的情况可以省略
ringBuffer.addGatingSequences(transProcessor.getSequence());
//把消息处理器提交到线程池
executors.submit(transProcessor);
System.out.println("主线程名"+Thread.currentThread().getName());
//如果存在多个消费者 那重复执行上面3行代码 把TradeHandler换成其它消费者类
Future<?> future= executors.submit(new Callable<Void>() { //提交给线程池
@Override
public Void call() throws Exception {
long seq;
System.out.println("执行call()方法的线程名"+Thread.currentThread().getName());
for(int i=0;i<10;i++){
seq = ringBuffer.next();//占个坑 --ringBuffer一个可用区块
ringBuffer.get(seq).setPrice(Math.random()*9999);//给这个区块放入 数据
ringBuffer.publish(seq);//发布这个区块的数据使handler(consumer)可见
}
return null;
}
});
future.get();//等待生产者结束
Thread.sleep(1000);//等上1秒,等消费都处理完成
transProcessor.halt();//通知事件(或者说消息)处理器 可以结束了(并不是马上结束!!!)
executors.shutdown();//终止线程
}
}
Trade.java
import java.util.concurrent.atomic.Atomicinteger;
public class Trade {
private String id;//ID
private String name;
private double price;//金额
private AtomicInteger count = new AtomicInteger(0);
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public double getPrice() {
return price;
}
public void setPrice(double price) {
this.price = price;
}
public AtomicInteger getCount() {
return count;
}
public void setCount(AtomicInteger count) {
this.count = count;
}
}
TradeHandler.java
import java.util.UUID;
import com.lmax.disruptor.EventHandler;
import com.lmax.disruptor.WorkHandler;
public class TradeHandler implements EventHandler<Trade> {
@Override
public void onEvent(Trade event, long sequence, boolean endOfBatch) throws Exception {
System.out.println("执行TradeHandler中onEvent(Trade event)方法的线程名"+Thread.currentThread().getName());
//这里做具体的消费逻辑
event.setId(UUID.randomUUID().toString());//简单生成下ID
System.out.println(event.getId());
}
}
在main主线程中创建单生产者的RingBuffer,使用了线程池来进行并发线程控制。涉及Future与Callable的使用,在main线程中创建子线程,执行call()方法,向RingBuffer中填充Trade类型的数据,并publish相应的sequence,使消费者TradeHandler对放到RingBuffer上的数据可见。执行代码future.get(),使主线程main阻塞等待子线程执行完毕。执行transProcessor.halt();等待消费者将消息消费完毕。最后,关闭线程池。
Eclipse中console控制台输出
直接使用RingBuffer(使用WorkHandler与WorkerPool)
Main2.java
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import com.lmax.disruptor.EventFactory;
import com.lmax.disruptor.ignoreExceptionHandler;
import com.lmax.disruptor.RingBuffer;
import com.lmax.disruptor.SequenceBarrier;
import com.lmax.disruptor.WorkHandler;
import com.lmax.disruptor.WorkerPool;
public class Main2 {
public static void main(String[] args) throws InterruptedException {
int BUFFER_SIZE=1024;
int THREAD_NUMBERS=4;
EventFactory<Trade> eventFactory = new EventFactory<Trade>() {
public Trade newInstance() {
return new Trade();
}
};
RingBuffer<Trade> ringBuffer = RingBuffer.createSingleProducer(eventFactory, BUFFER_SIZE);
SequenceBarrier sequenceBarrier = ringBuffer.newBarrier();
ExecutorService executor = Executors.newFixedThreadPool(THREAD_NUMBERS);
WorkHandler<Trade> handler = new TradeHandler();//充当消费者
WorkerPool<Trade> workerPool = new WorkerPool<Trade>(ringBuffer, sequenceBarrier, new IgnoreExceptionHandler(), handler);
workerPool.start(executor);
//下面这个生产8个数据
for(int i=0;i<8;i++){
long seq=ringBuffer.next();
ringBuffer.get(seq).setPrice(Math.random()*9999);
ringBuffer.publish(seq);
}
Thread.sleep(1000);
workerPool.halt();
executor.shutdown();
}
}
TradeHandler.java
import java.util.UUID;
import com.lmax.disruptor.WorkHandler;
public class TradeHandler implements WorkHandler<Trade> {
@Override
public void onEvent(Trade event) throws Exception {
System.out.println("执行TradeHandler中onEvent(Trade event)方法的线程名"+Thread.currentThread().getName());
//这里做具体的消费逻辑
event.setId(UUID.randomUUID().toString());//简单生成下ID
System.out.println(event.getId());
}
}
Eclipse的console输出:使用Disruptor实现菱形、六边形操作
Main.java
import java.util.concurrent.countdownlatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import com.lmax.disruptor.BusySpinWaitStrategy;
import com.lmax.disruptor.EventFactory;
import com.lmax.disruptor.dsl.Disruptor;
import com.lmax.disruptor.dsl.EventHandlerGroup;
import com.lmax.disruptor.dsl.ProducerType;
public class Main {
public static void main(String[] args) throws InterruptedException {
long beginTime=system.currenttimemillis();
int bufferSize=1024;
ExecutorService executor=Executors.newFixedThreadPool(8);
Disruptor<Trade> disruptor = new Disruptor<Trade>(new EventFactory<Trade>() {
@Override
public Trade newInstance() {
return new Trade();
}
}, bufferSize, executor, ProducerType.SINGLE, new BusySpinWaitStrategy());
//菱形操作
//使用disruptor创建消费者组C1,C2
EventHandlerGroup<Trade> handlerGroup =
disruptor.handleEventsWith(new Handler1(), new Handler2());
//声明在C1,C2完事之后执行JMS消息发送操作 也就是流程走到C3
handlerGroup.then(new Handler3());
//顺序操作
/**
disruptor.handleEventsWith(new Handler1()).
handleEventsWith(new Handler2()).
handleEventsWith(new Handler3());
*/
//六边形操作.
/**
Handler1 h1 = new Handler1();
Handler2 h2 = new Handler2();
Handler3 h3 = new Handler3();
Handler4 h4 = new Handler4();
Handler5 h5 = new Handler5();
disruptor.handleEventsWith(h1, h2);
disruptor.after(h1).handleEventsWith(h4);
disruptor.after(h2).handleEventsWith(h5);
disruptor.after(h4, h5).handleEventsWith(h3);
*/
disruptor.start();//启动
CountDownLatch latch=new CountDownLatch(1);
//生产者准备
executor.submit(new TradePublisher(latch, disruptor));
latch.await();//等待生产者完事.
disruptor.shutdown();
executor.shutdown();
System.out.println("总耗时:"+(System.currentTimeMillis()-beginTime));
}
}
TradePublisher.java
import java.util.Random;
import java.util.concurrent.CountDownLatch;
import com.lmax.disruptor.EventTranslator;
import com.lmax.disruptor.dsl.Disruptor;
public class TradePublisher implements Runnable {
Disruptor<Trade> disruptor;
private CountDownLatch latch;
private static int LOOP=1;//模拟百万次交易的发生
public TradePublisher(CountDownLatch latch,Disruptor<Trade> disruptor) {
this.disruptor=disruptor;
this.latch=latch;
}
@Override
public void run() {
TradeEventTranslator tradeTransloator = new TradeEventTranslator();
for(int i=0;i<LOOP;i++){
disruptor.publishEvent(tradeTransloator);
}
latch.countDown();
}
}
class TradeEventTranslator implements EventTranslator<Trade>{
private Random random=new Random();
@Override
public void translateTo(Trade event, long sequence) {
this.generateTrade(event);
}
private Trade generateTrade(Trade trade){
trade.setPrice(random.nextDouble()*9999);
return trade;
}
}
Handler1.java
import java.util.UUID;
import com.lmax.disruptor.EventHandler;
import com.lmax.disruptor.WorkHandler;
public class Handler1 implements EventHandler<Trade>,WorkHandler<Trade> {
@Override
public void onEvent(Trade event, long sequence, boolean endOfBatch) throws Exception {
this.onEvent(event);
}
@Override
public void onEvent(Trade event) throws Exception {
System.out.println("handler1: set name");
event.setName("h1");
Thread.sleep(1000);
}
}
Handler2.java
import com.lmax.disruptor.EventHandler;
public class Handler2 implements EventHandler<Trade> {
@Override
public void onEvent(Trade event, long sequence, boolean endOfBatch) throws Exception {
System.out.println("handler2: set price");
event.setPrice(17.0);
Thread.sleep(1000);
}
}
Handler3.java
import com.lmax.disruptor.EventHandler;
public class Handler3 implements EventHandler<Trade> {
@Override
public void onEvent(Trade event, long sequence, boolean endOfBatch) throws Exception {
System.out.println("handler3: name: " + event.getName() + " , price: " + event.getPrice() + "; instance: " + event.toString());
}
}
Eclipse的console输出如下:
Disruptor实现多生产者多消费者
order为Disruptor中的RingBuffer环中每一个槽存放数据的类型。Producer用于产生事件并放置到RingBuffer事件槽中。Consumer是用于消费RingBuffer中事件的类。
Order.java
public class Order {
private String id;//ID
private String name;
private double price;//金额
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public double getPrice() {
return price;
}
public void setPrice(double price) {
this.price = price;
}
}
Producer.java
import java.nio.ByteBuffer;
import java.util.UUID;
import java.util.concurrent.atomic.AtomicInteger;
import com.lmax.disruptor.EventTranslatorOneArg;
import com.lmax.disruptor.RingBuffer;
public class Producer {
private final RingBuffer<Order> ringBuffer;
public Producer(RingBuffer<Order> ringBuffer){
this.ringBuffer = ringBuffer;
}
/**
* onData用来发布事件,每调用一次就发布一次事件
* 它的参数会用过事件传递给消费者
*/
public void onData(String data){
//可以把ringBuffer看做一个事件队列,那么next就是得到下面一个事件槽
long sequence = ringBuffer.next();
try {
//用上面的索引取出一个空的事件用于填充(获取该序号对应的事件对象)
Order order = ringBuffer.get(sequence);
//获取要通过事件传递的业务数据
order.setId(data);
} finally {
//发布事件
//注意,最后的 ringBuffer.publish 方法必须包含在 finally 中以确保必须得到调用;如果某个请求的 sequence 未被提交,将会堵塞后续的发布操作或者其它的 producer。
ringBuffer.publish(sequence);
}
}
}
Consumer.java
import java.util.concurrent.atomic.AtomicInteger;
import com.lmax.disruptor.WorkHandler;
public class Consumer implements WorkHandler<Order>{
private String consumerId;
private static AtomicInteger count = new AtomicInteger(0);
public Consumer(String consumerId){
this.consumerId = consumerId;
}
@Override
public void onEvent(Order order) throws Exception {
System.out.println("当前消费者: " + this.consumerId + ",消费信息:" + order.getId());
count.incrementAndGet();
}
public int getCount(){
return count.get();
}
}
Main.javaimport java.nio.ByteBuffer;
import java.util.UUID;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.Executors;
import java.util.concurrent.atomic.AtomicInteger;
import com.lmax.disruptor.EventFactory;
import com.lmax.disruptor.ExceptionHandler;
import com.lmax.disruptor.RingBuffer;
import com.lmax.disruptor.SequenceBarrier;
import com.lmax.disruptor.WorkHandler;
import com.lmax.disruptor.WorkerPool;
import com.lmax.disruptor.YieldingWaitStrategy;
import com.lmax.disruptor.dsl.ProducerType;
public class Main {
//提供Integer的原子操作,在高并发场景中,多线程操作能够保证线程安全
private static AtomicInteger count = new AtomicInteger(0);
public static void main(String[] args) throws Exception {
//创建ringBuffer
RingBuffer<Order> ringBuffer =
RingBuffer.create(ProducerType.MULTI,
new EventFactory<Order>() {
@Override
public Order newInstance() {
return new Order();
}
},
1024 * 1024,
new YieldingWaitStrategy());
SequenceBarrier barriers = ringBuffer.newBarrier();//生产者消费者协调操作
//消费者数组
Consumer[] consumers = new Consumer[3];
for(int i = 0; i < consumers.length; i++){
consumers[i] = new Consumer("c" + i);
}
WorkerPool<Order> workerPool =
new WorkerPool<Order>(ringBuffer,
barriers,
new IntEventExceptionHandler(),
consumers);
//这一步的目的就是把消费者的位置信息引用注入到生产者,协调生产与消费的进度
ringBuffer.addGatingSequences(workerPool.getWorkerSequences());
workerPool.start(Executors.newFixedThreadPool(runtime.getRuntime().availableProcessors()));
final CountDownLatch latch = new CountDownLatch(1);
for (int i = 0; i < 3; i++) {
final Producer p = new Producer(ringBuffer);
new Thread(new Runnable() {//for循环创建3个线程,每个线程内部的for循环产生2个事件并publish
@Override
public void run() {
try {
System.out.println(Thread.currentThread().getName()+"ready!");
latch.await();//子线程阻塞
} catch (InterruptedException e) {
e.printstacktrace();
}
for(int j = 0; j < 2; j ++){
p.onData(Thread.currentThread().getName()+"产生的事件(数据)"+String.valueOf(count.addAndGet(1)));
}
}
}).start();
}
Thread.sleep(2000);
System.out.println("---------------开始生产-----------------");
latch.countDown();//解除对上面2个生产者子线程的阻塞,使其开始产生和publish事件
Thread.sleep(5000);
System.out.println("总数:" + consumers[0].getCount() );
}
static class IntEventExceptionHandler implements ExceptionHandler {
public void handleEventException(throwable ex, long sequence, Object event) {}
public void handleOnStartException(Throwable ex) {}
public void handleOnShutdownException(Throwable ex) {}
}
}
Eclipse的console输出
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