您现在的位置：程式碼之家 >> 編程語言 > >> Java 程式設計 >> Java 相關知識

100 行 Java 程式碼建構執行緒池：wait/notify 機制實作詳解

編輯：Java 相關知識

核心架構三類別

TestThreadPool：測試主程式，模擬客戶請求
ThreadPoolManager：池管理器，負責初始化與分派
SimpleThread：工作執行緒，實際處理任務

完整實作程式碼

SimpleThread.java (工作執行緒)

class SimpleThread extends Thread {
    private boolean running = false;
    private String task;
    
    SimpleThread(int id) {
        super("Worker-" + id);
        System.out.println(getName() + " 已啟動");
    }
    
    synchronized void assign(String task) {
        this.task = task;
        this.running = true;
        notify(); // 喚醒等待中的執行緒
    }
    
    synchronized boolean isIdle() { return !running; }
    
    public void run() {
        try {
            while (true) {
                synchronized (this) {
                    while (!running) wait(); // 閒置等待
                }
                // 處理任務
                System.out.println(getName() + " 處理: " + task + " ... 完成");
                Thread.sleep(5000); // 模擬耗時操作
                System.out.println(getName() + " 進入閒置");
                synchronized (this) { running = false; }
            }
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
        }
    }
}

ThreadPoolManager.java (管理器)

class ThreadPoolManager {
    private final List workers = new ArrayList<>();
    
    ThreadPoolManager(int size) {
        for (int i = 1; i <= size; i++) {
            SimpleThread t = new SimpleThread(i);
            workers.add(t);
            t.start();
        }
    }
    
    void process(String task) {
        for (SimpleThread t : workers) {
            if (t.isIdle()) {
                t.assign(task);
                return;
            }
        }
        System.out.println("執行緒池已滿，請稍後再試");
    }
}

TestThreadPool.java (測試)

public class TestThreadPool {
    public static void main(String[] args) throws IOException {
        ThreadPoolManager pool = new ThreadPoolManager(10);
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String input;
        while ((input = br.readLine()) != null) {
            pool.process(input);
        }
    }
}