disruptor简单示例
我们通过一个简单示例来演示disruptor的使用
1.生产者和消费者操作的数据
Person.java
========================
public class Person {
private String name;
private int age;
private String gender;
private String mobile;
public Person(){}
public Person(String name, int age, String gender, String mobile){
this.name = name;
this.age = age;
this.gender = gender;
this.mobile = mobile;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public String getMobile() {
return mobile;
}
public void setMobile(String mobile) {
this.mobile = mobile;
}
}
2.PersonEvent.java
========================
import com.lmax.disruptor.EventFactory;
/**
* 消费事件
*/
public class PersonEvent {
private Person person;
public Person getPerson() {
return person;
}
public void setPerson(Person person) {
this.person = person;
}
public final static EventFactory
public PersonEvent newInstance(){
return new PersonEvent();
}
};
}
3.消费事件处理处理器
PersonEventHandler.java
========================
import com.lmax.disruptor.EventHandler;
/**
* 消费事件处理处理器
*/
public class PersonEventHandler implements EventHandler
public PersonEventHandler(){
// DataSendHelper.start();
}
@Override
public void onEvent(PersonEvent event, long sequence, boolean endOfBatch)
throws Exception {
Person person = event.getPerson();
System.out.println("name = "+person.getName()+", age = "+ person.getAge()+", gender = "+ person.getGender() +", mobile = "+person.getMobile());
}
}
4.ringbuffer的初始化
PersonHelper.java
========================
import com.lmax.disruptor.BatchEventProcessor;
import com.lmax.disruptor.RingBuffer;
import com.lmax.disruptor.SequenceBarrier;
import com.lmax.disruptor.SingleThreadedClaimStrategy;
import com.lmax.disruptor.YieldingWaitStrategy;
public class PersonHelper {
private static PersonHelper instance;
private static boolean inited = false;
/**
* ringBuffer的容量，必须是2的N次方
*/
private static final int BUFFER_SIZE = 256;
private RingBuffer
private SequenceBarrier sequenceBarrier;
private PersonEventHandler handler;
private BatchEventProcessor
public PersonHelper(){
//参数1 事件
//参数2 单线程使用
//参数3 等待策略
ringBuffer = new RingBuffer
new SingleThreadedClaimStrategy(BUFFER_SIZE), new YieldingWaitStrategy());
//获取生产者的位置信息
sequenceBarrier = ringBuffer.newBarrier();
//消费者
handler=new PersonEventHandler();
//事件处理器，监控指定ringBuffer,有数据时通知指定handler进行处理
batchEventProcessor = new BatchEventProcessor
//传入所有消费者线程的序号
ringBuffer.setGatingSequences(batchEventProcessor.getSequence());
}
/**
* 启动消费者线程，实际上调用了AudioDataEventHandler中的onEvent方法进行处理
*/
public static void start(){
instance = new PersonHelper();
Thread thread = new Thread(instance.batchEventProcessor);
thread.start();
inited = true;
}
/**
* 停止
*/
public static void shutdown(){
if(!inited){
throw new RuntimeException("EncodeHelper还没有初始化！");
}else{
instance.doHalt();
}
}
private void doHalt() {
batchEventProcessor.halt();
}
private void doProduce(Person person){
//获取下一个序号
long sequence = ringBuffer.next();
//写入数据
ringBuffer.get(sequence).setPerson(person);
//通知消费者该资源可以消费了
ringBuffer.publish(sequence);
}
/**
* 生产者压入生产数据
* @param data
*/
public static void produce(Person person){
if(!inited){
throw new RuntimeException("EncodeHelper还没有初始化！");
}else{
instance.doProduce(person);
}
}
}
5. 主函数入口
public class Test {
/**
* @param args
*/
public static void main(String[] args) {
PersonHelper.start();
for(int i=0 ; i<20; i++){
Person p = new Person("jbgtwang"+i, i , "男", "1234566"+i);
//生产者生产数据
PersonHelper.produce(p);
}
}
}
====================================
要注意的：
1. 该示例在电脑上可以正常运行，在android上运行则Unsafe类报错。
网上有人说将disruptor中com.lmax.disruptor.util.Util类中反射调用Unsafe “theUnsafe”的地方改为"THE_ONE"，重新编译一下就可以用了
2. ringBuffer的容量，必须是2的N次方