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import java.lang.ScopedValue;

public class ScopedValueExample {

    // 定义一个静态最终的 ScopedValue 对象

    static final ScopedValue<String> USER = ScopedValue.newInstance();

}

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ScopedValue.where(USER, "Alice").run(() -> {

    System.out.println("Current User: " + USER.get()); // 输出 "Alice"

});

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try {

    System.out.println("Outside Scope: " + USER.get());

} catch (IllegalStateException e) {

    System.out.println("无法在作用域外访问 ScopedValue");

}

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ScopedValue.where(USER, "Bob").run(() -> {

    System.out.println("Inner Scope: " + USER.get()); // 输出 "Bob"

});

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try (var executor = Executors.newVirtualThreadPerTaskExecutor()) {

    for (int i = 0; i < 5; i++) {

        int id = i;

        executor.submit(() -> {

            ScopedValue.where(REQUEST_ID, "Request-" + id).run(() -> {

                System.out.println("Thread: " + Thread.currentThread() +

                                   ", Request ID: " + REQUEST_ID.get());

            });

        });

    }

}