基于线程池的大目录拷贝

以下是基于线程池的大目录拷贝的示例代码：

import os
import shutil
import threading

class CopyTask:
    def __init__(self, src, dst):
        self.src = src
        self.dst = dst

    def run(self):
        shutil.copytree(self.src, self.dst)
        print(f"Copy from {self.src} to {self.dst} completed.")

class ThreadPool:
    def __init__(self, num_threads):
        self.num_threads = num_threads
        self.task_queue = []
        self.threads = []

    def start(self):
        for i in range(self.num_threads):
            thread = threading.Thread(target=self.run)
            self.threads.append(thread)
            thread.start()

    def run(self):
        while True:
            task = None
            with threading.Lock():
                if self.task_queue:
                    task = self.task_queue.pop(0)

            if task:
                task.run()
            else:
                break

    def submit(self, task):
        with threading.Lock():
            self.task_queue.append(task)

    def join(self):
        for thread in self.threads:
            thread.join()

if __name__ == "__main__":
    src = "/path/to/source"
    dst = "/path/to/destination"
    num_threads = 4

    # Create thread pool and start threads
    pool = ThreadPool(num_threads)
    pool.start()

    # Submit copy tasks to thread pool
    for dirpath, dirnames, filenames in os.walk(src):
        for dirname in dirnames:
            src_path = os.path.join(dirpath, dirname)
            dst_path = src_path.replace(src, dst)
            task = CopyTask(src_path, dst_path)
            pool.submit(task)

    # Wait for all tasks to complete
    pool.join()

    print("All copy tasks completed.")

此代码使用了一个`CopyTask`类来表示一个目录拷贝任务，该任务包含源目录和目标目录。线程池类`ThreadPool`包含一个任务队列和一组线程，可以提交任务以异步执行。在主函数中，使用`os.walk`遍历源目录中的所有目录，并将每个目录拷贝任务提交到线程池中。最后，等待所有任务完成后，输出完成消息。