代码示例：
public interface Data { String getRequest();}public class FutureData implements Data{ private RealData realData ; private boolean isReady = false; public synchronized void setRealData(RealData realData) {
//如果已经装载完毕了，就直接返回
if(isReady){
return;
}
//如果没装载，进行装载真实对象
this.realData = realData;
isReady = true;
//进行通知
notify();
} @Override
public synchronized String getRequest() {
//如果没装载好 程序就一直处于阻塞状态
while(!isReady){
try {
wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
//装载好直接获取数据即可
return this.realData.getRequest();
}}public class RealData implements Data{ private String result ; public RealData (String queryStr){
System.out.println("根据" + queryStr + "进行查询，这是一个很耗时的操作..");
try {
Thread.sleep(5000);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("操作完毕，获取结果");
result = "查询结果";
} @Override
public String getRequest() {
return result;
}}public class FutureClient { public Data request(final String queryStr){
//1 我想要一个代理对象（Data接口的实现类）先返回给发送请求的客户端，告诉他请求已经接收到，可以做其他的事情
final FutureData futureData = new FutureData();
//2 启动一个新的线程，去加载真实的数据，传递给这个代理对象
new Thread(new Runnable() {
@Override
public void run() {
//3 这个新的线程可以去慢慢的加载真实对象，然后传递给代理对象
RealData realData = new RealData(queryStr);
futureData.setRealData(realData);
}
}).start(); return futureData;
}}public class Main { public static void main(String[] args) throws InterruptedException { FutureClient fc = new FutureClient();
Data data = fc.request("请求参数");
System.out.println("请求发送成功!");
System.out.println("做其他的事情..."); String result = data.getRequest();
System.out.println(result); }
}
具体一点，代码实现流程应该是这样的：
代码示例：
public class Task { private int id;
private int price ;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public int getPrice() {
return price;
}
public void setPrice(int price) {
this.price = price;
} }public class Master { //1 有一个盛放任务的容器
private ConcurrentLinkedQueue<Task> workQueue = new ConcurrentLinkedQueue<Task>(); //2 需要有一个盛放worker的集合
private HashMap<String, Thread> workers = new HashMap<String, Thread>(); //3 需要有一个盛放每一个worker执行任务的结果集合
private ConcurrentHashMap<String, Object> resultMap = new ConcurrentHashMap<String, Object>(); //4 构造方法
public Master(Worker worker , int workerCount){
worker.setWorkQueue(this.workQueue);
worker.setResultMap(this.resultMap); for(int i = 0; i < workerCount; i ++){
this.workers.put(Integer.toString(i), new Thread(worker));
} } //5 需要一个提交任务的方法
public void submit(Task task){
this.workQueue.add(task);
} //6 需要有一个执行的方法，启动所有的worker方法去执行任务
public void execute(){
for(Map.Entry<String, Thread> me : workers.entrySet()){
me.getValue().start();
}
} //7 判断是否运行结束的方法
public boolean isComplete() {
for(Map.Entry<String, Thread> me : workers.entrySet()){
if(me.getValue().getState() != Thread.State.TERMINATED){
return false;
}
}
return true;
} //8 计算结果方法
public int getResult() {
int priceResult = 0;
for(Map.Entry<String, Object> me : resultMap.entrySet()){
priceResult += (Integer)me.getValue();
}
return priceResult;
}
}public class Worker implements Runnable { private ConcurrentLinkedQueue<Task> workQueue;
private ConcurrentHashMap<String, Object> resultMap; public void setWorkQueue(ConcurrentLinkedQueue<Task> workQueue) {
this.workQueue = workQueue;
} public void setResultMap(ConcurrentHashMap<String, Object> resultMap) {
this.resultMap = resultMap;
} @Override
public void run() {
while(true){
Task input = this.workQueue.poll();
if(input == null) break;
Object output = handle(input);
this.resultMap.put(Integer.toString(input.getId()), output);
}
} private Object handle(Task input) {
Object output = null;
try {
//处理任务的耗时。。 比如说进行操作数据库。。。
Thread.sleep(500);
output = input.getPrice();
} catch (InterruptedException e) {
e.printStackTrace();
}
return output;
}
}public class Main { public static void main(String[] args) { Master master = new Master(new Worker(), 20); Random r = new Random();
for(int i = 1; i <= 100; i++){
Task t = new Task();
t.setId(i);
t.setPrice(r.nextInt(1000));
master.submit(t);
}
master.execute();
long start = System.currentTimeMillis(); while(true){
if(master.isComplete()){
long end = System.currentTimeMillis() - start;
int priceResult = master.getResult();
System.out.println("最终结果：" + priceResult + ", 执行时间：" + end);
break;
}
} }
}
代码示例：
public final class Data { private String id;
private String name; public Data(String id, String name){
this.id = id;
this.name = name;
} 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;
} @Override
public String toString(){
return "{id: " + id + ", name: " + name + "}";
}
}public class Consumer implements Runnable{ private BlockingQueue<Data> queue; public Consumer(BlockingQueue queue){
this.queue = queue;
} //随机对象
private static Random r = new Random(); @Override
public void run() {
while(true){
try {
//获取数据
Data data = this.queue.take();
//进行数据处理。休眠0 - 1000毫秒模拟耗时
Thread.sleep(r.nextInt(1000));
System.out.println("当前消费线程：" + Thread.currentThread().getName() + "， 消费成功，消费数据为id: " + data.getId());
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}public class Provider implements Runnable{ //共享缓存区
private BlockingQueue<Data> queue;
//多线程间是否启动变量，有强制从主内存中刷新的功能。即时返回线程的状态
private volatile boolean isRunning = true;
//id生成器
private static AtomicInteger count = new AtomicInteger();
//随机对象
private static Random r = new Random(); public Provider(BlockingQueue queue){
this.queue = queue;
} @Override
public void run() {
while(isRunning){
try {
//随机休眠0 - 1000 毫秒 表示获取数据(产生数据的耗时)
Thread.sleep(r.nextInt(1000));
//获取的数据进行累计...
int id = count.incrementAndGet();
//比如通过一个getData方法获取了
Data data = new Data(Integer.toString(id), "数据" + id);
System.out.println("当前线程:" + Thread.currentThread().getName() + ", 获取了数据，id为:" + id + ", 进行装载到公共缓冲区中...");
if(!this.queue.offer(data, 2, TimeUnit.SECONDS)){
System.out.println("提交缓冲区数据失败....");
//do something... 比如重新提交
}
} catch (InterruptedException e) {
e.printStackTrace();
}
}
} public void stop(){
this.isRunning = false;
}}public class Main { public static void main(String[] args) throws Exception {
//内存缓冲区
BlockingQueue<Data> queue = new LinkedBlockingQueue<Data>(10);
//生产者
Provider p1 = new Provider(queue); Provider p2 = new Provider(queue);
Provider p3 = new Provider(queue);
//消费者
Consumer c1 = new Consumer(queue);
Consumer c2 = new Consumer(queue);
Consumer c3 = new Consumer(queue);
//创建线程池运行,这是一个缓存的线程池，可以创建无穷大的线程，没有任务的时候不创建线程。空闲线程存活时间为60s（默认值） ExecutorService cachePool = Executors.newCachedThreadPool();
cachePool.execute(p1);
cachePool.execute(p2);
cachePool.execute(p3);
cachePool.execute(c1);
cachePool.execute(c2);
cachePool.execute(c3); try {
Thread.sleep(3000);
} catch (InterruptedException e) {
e.printStackTrace();
}
p1.stop();
p2.stop();
p3.stop();
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
e.printStackTrace();
}
// cachePool.shutdown();
// cachePool.shutdownNow(); }
}
