Future和FutureTask的区别

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Future和FutureTask的区别

Future接口

Future是Java异步计算结果的抽象，表示异步任务的执行结果。

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public interface Future<V> {
    V get() throws InterruptedException, ExecutionException;
    V get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException;
    boolean cancel(boolean mayInterruptIfRunning);
    boolean isCancelled();
    boolean isDone();
}

FutureTask

FutureTask是Future的实现类，同时实现了Runnable接口。

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public class FutureTask<V> implements RunnableFuture<V> {}
public interface RunnableFuture<V> extends Runnable, Future<V> {}

使用区别

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// Future用法
ExecutorService executor = Executors.newSingleThreadExecutor();
Future<String> future = executor.submit(() -> "result");
String result = future.get();

// FutureTask用法
FutureTask<String> task = new FutureTask<>(() -> "result");
new Thread(task).start();
String result = task.get();

适用场景

  • Future：提交给线程池，返回Future
  • FutureTask：可作为Runnable直接在线程中执行

总结

FutureTask更灵活，可单独运行；Future配合线程池使用更方便。