来自带有回调的异步函数的Java同步函数

import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class AsyncToSyncExample {
    public static void main(String[] args) throws ExecutionException, InterruptedException {
        // 创建一个线程池
        ExecutorService executorService = Executors.newFixedThreadPool(1);

        // 异步函数，接受一个回调函数作为参数
        void asyncFunction(CompletableFuture<String> future) {
            // 模拟异步操作
            executorService.submit(() -> {
                try {
                    Thread.sleep(1000);
                    // 异步操作完成后，调用回调函数并传递结果
                    future.complete("异步操作结果");
                } catch (InterruptedException e) {
                    future.completeExceptionally(e);
                }
            });
        }

        // 创建一个CompletableFuture对象
        CompletableFuture<String> future = new CompletableFuture<>();

        // 调用异步函数，并传入CompletableFuture对象
        asyncFunction(future);

        // 阻塞等待异步操作结果，并获取结果
        String result = future.get();

        System.out.println("同步函数获取到结果：" + result);

        // 关闭线程池
        executorService.shutdown();
    }
}