lambda表达式在Java多线程编程中的应用

Runnable task = () -> {
    // 执行线程任务
};

Thread thread = new Thread(task);

ExecutorService executorService = Executors.newFixedThreadPool(5);

List<Callable<Integer>> tasks = List.of(() -> 1, () -> 2, () -> 3);

List<Future<Integer>> futures = executorService.invokeAll(tasks);

for (Future<Integer> future : futures) {
    // 获取线程结果
    Integer result = future.get();
}

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class FileLineCounter {

    public static void main(String[] args) {
        // 获取文件路径列表
        List<Path> paths = Files.list(Path.of("files")).toList();

        // 创建线程池
        ExecutorService executorService = Executors.newFixedThreadPool(5);

        // 使用lambda表达式创建任务
        List<Callable<Integer>> tasks = paths.stream()
            .map(path -> () -> {
                try {
                    // 读取文件并计数行数
                    return Files.lines(path).count();
                } catch (IOException e) {
                    // 处理异常
                    return 0;
                }
            })
            .toList();

        // 提交任务并获取结果
        List<Future<Integer>> futures = executorService.invokeAll(tasks);

        // 计算总行数
        int totalLines = 0;
        for (Future<Integer> future : futures) {
            try {
                totalLines += future.get();
            } catch (InterruptedException | ExecutionException e) {
                // 处理异常
            }
        }

        // 打印总行数
        System.out.println("Total lines: " + totalLines);

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