线程池的毒丸方法实现线程池的配比热切换
需求:
线程池(采用ThreadPoolExecutor)有2类共计10个作战区线程在跑,都是从blockingQueue里面取武器进行消费,其中5个是对德,另外5个对日,另外有n个生产者线程负责对blockingQueue发送武器;
现在由于中途德国率先投降,需要削减对德的驻军,请问这个多线程代码框架如何设计?
要求:
尽可能采用juc原始的多线程工具;
不允许使用redis和db相关;
blockingQueue里面的消息要全部被消费后才能退出;
/**
* @Title: ArsenalTester.java
* @Package: inter
* @Description: TODO(用一句话描述该文件做什么)
* @author: 陈元俊
* @date: 2019年5月24日 下午12:42:23
* @version V1.0
* @Copyright: 2019 All rights reserved.
*/
package inter;
import java.util.UUID;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
/**
* @ClassName: ArsenalTester
* @Description: 模拟二战武器生产
* @author: 陈元俊
* @date: 2019年5月24日 下午12:42:23
*/
public class ArsenalTester {
private static final String CANCEL_NAZI = "CANCEL_NAZI";
private static final String CANCEL_JAPAN = "CANCEL_JAPAN";
/* 兵工厂,这里是生产者 */
public static class Arsenal implements Runnable {
private BlockingQueue<String> equipments;
public static volatile boolean stop = false; // 全局的兵工厂生产开关
public Arsenal(BlockingQueue<String> equipments) {
this.equipments = equipments;
}
public static AtomicInteger counts = new AtomicInteger();
@Override
public void run() {
while (!stop) {
String equip = UUID.randomUUID().toString();
// System.out.println("Arsenal produced " + equip);
equipments.add(equip);
counts.incrementAndGet();
try {
Thread.sleep(10);
} catch (InterruptedException e) {
}
}
System.out.println("stop producing!");
}
}
/* 负责对日的司令部 默认5个战区,从兵工厂要装备*/
public static class FightJapanHQ implements Runnable {
private BlockingQueue<String> equipments;
public static AtomicInteger jpcounts = new AtomicInteger();
public FightJapanHQ(BlockingQueue<String> equipments) {
this.equipments = equipments;
}
@Override
public void run() {
while (true) {
String equip;
try {
equip = equipments.take();
if (equip.equals(CANCEL_JAPAN)) {
System.out.println("-------------------------FightJapanHQ demolished!"); // 毒丸收到,撤销战区
return;
} else if (CANCEL_NAZI.equals(equip)) {
// System.out.println("DONT GIVE ME NAZI!");
equipments.add(equip);
continue;
}
jpcounts.incrementAndGet();
System.out.println("Asia HQ fetch " + equip);
} catch (InterruptedException e) {
System.out.println("-=-=-=cannot get");
}
}
}
}
/* 负责对德的司令部,默认5个战区,从兵工厂要装备 */
public static class FightNaziHQ implements Runnable {
private BlockingQueue<String> equipments;
public static AtomicInteger nzcounts = new AtomicInteger();
public FightNaziHQ(BlockingQueue<String> equipments) {
this.equipments = equipments;
}
@Override
public void run() {
while (true) {
try {
String equip = equipments.take();
if (CANCEL_NAZI.equals(equip)) {
System.out.println("-------------------------FightNaziHQ demolished!"); // 毒丸收到,撤销战区
return;
} else if (CANCEL_JAPAN.equals(equip)) {
// System.out.println("DONT GIVE ME JP!");
equipments.add(equip);
continue;
}
nzcounts.incrementAndGet();
System.out.println("Euro HQ fetch " + equip);
} catch (InterruptedException e) {
System.out.println("-=-=-=cannot get");
}
}
}
}
public static void main(String[] args) throws Exception {
ExecutorService battleField = Executors.newCachedThreadPool();
BlockingQueue<String> equipments = new ArrayBlockingQueue<>(1000);
new Thread(new Runnable() {
@Override
public void run() {
for (int i = 0; i < 10; i++) {
battleField.submit(new Arsenal(equipments));
}
for (int i = 0; i < 5; i++) {
battleField.submit(new FightNaziHQ(equipments));
battleField.submit(new FightJapanHQ(equipments));
}
System.out.println("i am out!"); // 发射后不管
}
}).start();
Thread.sleep(5000);
System.out.println("=============================Nazi surrendered!============================="); // 德国先投降
for (int i = 0; i < 4; i++) {
boolean val = equipments.add(CANCEL_NAZI); // 这里取消掉4个对德战区,保留1个
}
Thread.sleep(5000);
Arsenal.stop = true;
System.out.println("Celebrate peace"); // 二战胜利!马放南山,但此刻Queue里面大概率仍然有订单!
for (int i = 0; i < 1; i++) {
boolean val = equipments.add(CANCEL_NAZI); // 别忘了战后取消剩下的1个对德战区
// System.out.println("put res " + val);
}
for (int i = 0; i < 5; i++) {
boolean val = equipments.add(CANCEL_JAPAN); // 取消剩下的5个对日战区
// System.out.println("put res " + val);
}
battleField.shutdown();
while (!battleField.isTerminated()) {
}
System.out.println("Totally produced " + Arsenal.counts);
System.out.println("Finally FightNaziHQ received " + FightNaziHQ.nzcounts.intValue() + " and FightJapanHQ received "
+ FightJapanHQ.jpcounts.intValue());
System.out.println("equipments now remains " + equipments.size());
}
}