Question

我是新来的，很抱歉，如果我把这个说错了话题？

我的问题：

class TaskEol implements Callable<ArrayList<Coordinates>> {
        ArrayList<CoordinatesEolEwp> coordinates = new ArrayList<Coordinates>();

        public ArrayList<Coordinates> call() throws Exception {
            new Thread (() -> {
                indicatorDatabaseAction.setVisible(true);
                coordinates = loadCoordinatesOutOfDatabase();
                indicatorDatabaseAction.setVisible(false);
            }).start();


            return coordinates;
        }
    }

如何在返回之前等待数据库在对象中写入坐标？

Answer 1

沿着这些方向，myCallable是你的可赎回但没有Thread的东西，即

public ArrayList<Coordinates> call() throws Exception {
    indicatorDatabaseAction.setVisible(true);
    coordinates = loadCoordinatesOutOfDatabase();
    indicatorDatabaseAction.setVisible(false);

    return coordinates;
}

...然后

ExecutorService e = Executors.newSingleThreadExecutor();
Future<ArrayList<Coordinates>> f = e.submit(myCallable);

// Note that Future.get() blocks until results are ready
ArrayList<Coordinates> coords = f.get();

Java Callable - ＆gt;启动线程并等待

1 个答案: