1 篇博文 含有标签「JDK20」

public class EnhancedVirtualThreadExample {
    public static void main(String[] args) throws Exception {
        // 创建虚拟线程
        Thread.Builder.OfVirtual builder = Thread.ofVirtual();
        Thread vThread = builder.start(() -> {
            System.out.println("在虚拟线程中运行");
        });
        
        // 使用虚拟线程执行器处理大量任务
        try (var executor = Executors.newVirtualThreadPerTaskExecutor()) {
            List<Future<String>> futures = new ArrayList<>();
            
            // 提交多个任务
            for (int i = 0; i < 1000; i++) {
                final int taskId = i;
                futures.add(executor.submit(() -> {
                    // 模拟 IO 操作
                    Thread.sleep(Duration.ofMillis(100));
                    return "任务 " + taskId + " 完成";
                }));
            }
            
            // 收集结果
            for (Future<String> future : futures) {
                System.out.println(future.get());
            }
        }
        
        // 使用结构化并发
        try (var scope = new StructuredTaskScope.ShutdownOnFailure()) {
            // 并行执行多个操作
            Future<String> auth = scope.fork(() -> authenticateUser("user123"));
            Future<List<String>> perms = scope.fork(() -> fetchPermissions("user123"));
            Future<UserProfile> profile = scope.fork(() -> loadUserProfile("user123"));
            
            scope.join();           // 等待所有任务完成
            scope.throwIfFailed();  // 检查失败
            
            // 处理结果
            processUserData(
                auth.resultNow(),
                perms.resultNow(),
                profile.resultNow()
            );
        }
    }
    
    // 模拟用户认证
    private static String authenticateUser(String userId) throws Exception {
        Thread.sleep(100);
        return "TOKEN_" + userId;
    }
    
    // 模拟权限获取
    private static List<String> fetchPermissions(String userId) throws Exception {
        Thread.sleep(150);
        return List.of("READ", "WRITE", "EXECUTE");
    }
    
    // 模拟用户档案加载
    private static UserProfile loadUserProfile(String userId) throws Exception {
        Thread.sleep(200);
        return new UserProfile(userId, "张三", "zhang@example.com");
    }
    
    // 处理用户数据
    private static void processUserData(
        String token,
        List<String> permissions,
        UserProfile profile
    ) {
        System.out.printf(
            "用户 %s 已认证，权限：%s，邮箱：%s%n",
            profile.name(),
            String.join(",", permissions),
            profile.email()
        );
    }
    
    record UserProfile(String id, String name, String email) {}
}