在Java中，可以使用wait()和notify()或notifyAll()方法來實現生產者-消費者模式。這些方法是Object類的一部分，用于線程間的通信。下面是一個簡單的生產者-消費者模式示例：

1. 首先，創建一個共享資源類，例如一個緩沖區（Buffer）：

public class Buffer {
    private int data;
    private boolean empty = true;

    public synchronized void put(int data) {
        while (!empty) {
            try {
                wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        this.data = data;
        empty = false;
        notifyAll();
    }

    public synchronized int get() {
        while (empty) {
            try {
                wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        empty = true;
        notifyAll();
        return data;
    }
}

2. 創建生產者線程類：

public class Producer implements Runnable {
    private Buffer buffer;

    public Producer(Buffer buffer) {
        this.buffer = buffer;
    }

    @Override
    public void run() {
        for (int i = 0; i < 10; i++) {
            System.out.println("Produced: " + i);
            buffer.put(i);
        }
    }
}

3. 創建消費者線程類：

public class Consumer implements Runnable {
    private Buffer buffer;

    public Consumer(Buffer buffer) {
        this.buffer = buffer;
    }

    @Override
    public void run() {
        for (int i = 0; i < 10; i++) {
            int data = buffer.get();
            System.out.println("Consumed: " + data);
        }
    }
}

4. 在主程序中創建生產者和消費者線程，并啟動它們：

public class Main {
    public static void main(String[] args) {
        Buffer buffer = new Buffer();
        Thread producerThread = new Thread(new Producer(buffer));
        Thread consumerThread = new Thread(new Consumer(buffer));

        producerThread.start();
        consumerThread.start();
    }
}

運行上述代碼，你將看到生產者和消費者線程交替執行，生產者將數據放入緩沖區，消費者從緩沖區中取出數據。這就是一個簡單的生產者-消費者模式實現。