Master-Worker模式 多线程设计模式

Master-Worker模式 多线程设计模式

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常用的并行计算模式。它的核心思想是系统由两类进程协作工作：Master-Worker进程。Master负责接收和分配任务，Worker负责处理子任务。当各个Worker子进程处理完成后，会将结果返回给Master,由master做归纳和总结。大任务分解小任务，并行执行。

public class Main {    public static void main(String[] args) {        Master master = new Master(new Worker(), 5);        for(int i = 0; i<10; i++){            Task task = new Task();            task.setId(i);            task.setName("任务"+i);            master.submit(task);        }        master.execute();        while(true){            if (master.isComplete()) {                break;            }        }        ConcurrentHashMap<String, Object> resultMap = master.getResultMap();        for(Map.Entry<String, Object> me : resultMap.entrySet()){            System.out.println(me.getKey() + "   " + me.getValue());        }    }}public class Master {    private ConcurrentLinkedQueue<Task> workQueue = new ConcurrentLinkedQueue<>();    private Map<String, Thread> workers = new HashMap<>();    private ConcurrentHashMap<String, Object> resultMap = new ConcurrentHashMap<>();    public ConcurrentHashMap<String, Object> getResultMap() {        return resultMap;    }    public void setResultMap(ConcurrentHashMap<String, Object> resultMap) {        this.resultMap = resultMap;    }    public Master(Worker worker, int workerCount) {        worker.setWorkQueue(this.workQueue);        worker.setResultMap(this.resultMap);        for (int i = 0; i < workerCount; i++) {            //key表示每一个worker的名字，value表示线程执行对象            workers.put("子节点" + i, new Thread(worker));        }    }    public void submit(Task task){        this.workQueue.add(task);    }    public void execute(){        for (Map.Entry<String, Thread> me : workers.entrySet()) {            me.getValue().start();        }    }    public boolean isComplete() {        for (Map.Entry<String, Thread> me : workers.entrySet()) {            if (me.getValue().getState() != Thread.State.TERMINATED) {                return false;            }        }        return true;    }}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 (null == input) break;            Object output = handle(input);            this.resultMap.put(Integer.toString(input.getId()), output);        }    }    private Object handle(Task input) {        Object output = null;        try {            Thread.sleep(500);            output = input.getName();        } catch (InterruptedException e) {            // TODO Auto-generated catch block            e.printStackTrace();        }        return output;    }}public class Task {    private int id;    private String name;    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }}