1. 程式人生 > >MasterWorker模式講解

MasterWorker模式講解


import java.util.Random;

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("最終結果:" + priceResult + ", 執行時間:" + end);
				break;
			}
		}
		
	}
}

 


import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentLinkedQueue;

public class Master {

	//1 有一個盛放任務的容器
	private ConcurrentLinkedQueue<Task> workQueue = new ConcurrentLinkedQueue<Task>();
	
	//2 需要有一個盛放worker的集合
	private HashMap<String, Thread> workers = new HashMap<String, Thread>();
	
	//3 需要有一個盛放每一個worker執行任務的結果集合
	private ConcurrentHashMap<String, Object> resultMap = new ConcurrentHashMap<String, Object>();
	
	//4 構造方法
	public Master(Worker worker , int workerCount){
		// 每一個worker物件都需要有Master的引用 workerQueue用於任務的領取,resultMap用於任務的提交
		worker.setWorkQueue(this.workQueue);
		worker.setResultMap(this.resultMap);
		
		for(int i = 0; i < workerCount; i ++){
			// key表示每一個worker的名字,value表示執行緒執行物件
			this.workers.put("子節點"+Integer.toString(i), new Thread(worker));
		}
		
	}
	
	//5 需要一個提交任務的方法
	public void submit(Task task){
		this.workQueue.add(task);
	}
	
	//6 需要有一個執行的方法,啟動所有的worker方法去執行任務
	public void execute(){
		for(Map.Entry<String, Thread> me : workers.entrySet()){
			me.getValue().start();
		}
	}

	//7 判斷是否執行結束的方法
	public boolean isComplete() {
		for(Map.Entry<String, Thread> me : workers.entrySet()){
			if(me.getValue().getState() != Thread.State.TERMINATED){
				return false;
			}
		}		
		return true;
	}

	//8 計算結果方法
	public int getResult() {
		int priceResult = 0;
		for(Map.Entry<String, Object> me : resultMap.entrySet()){
			priceResult += (Integer)me.getValue();
		}
		return priceResult;
	}
	
	
	
	
	
	
	
	
	
	
	
	
	
	
}

 


public class 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;
	} 
	
}

 


import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentLinkedQueue;

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;
			// 真正的去做業務處理
			Object output = handle(input);
			this.resultMap.put(Integer.toString(input.getId()), output);
		}
	}

	private Object handle(Task input) {
		Object output = null;
		try {
			//處理任務的耗時。。 比如說進行操作資料庫。。。
			Thread.sleep(500);
			output = input.getPrice();
		} catch (InterruptedException e) {
			e.printStackTrace();
		}
		return output;
	}



}
public static void main(String[] args) {
		System.out.println(Runtime.getRuntime().availableProcessors());
	}