java - 对象创建时的 HandlerThread 同步

Question

我有一个线程正在等待处理程序线程创建一个对象，它将初始化一个指向该对象的指针。我读到您无法同步指针的引用更改。我该如何去做呢？

我首先尝试让线程返回对象，但这仍然不起作用。这是我到目前为止所拥有的。“dataHolder”是正在创建的对象，我想等待。“lThread”是线程2

主题 1:

Data dataHolder= null;

        lThread.run();
        synchronized (lThread) {
            while(lThread.locked){

                try {

                    lThread.wait(3000);
                }
                catch(InterruptedException e){

                }
            }
           dataHolder = lThread.dataHolder;
        }

线程2的run方法:

synchronized (this) {

            //get gps data
            LatLongAlt lla = getLatLonAlt();
            if (lla == null) {
                return;
            }
            //create image data holder
            dataHolder = new Data(lla, mSensor.getAzimuth(), -1 * mSensor.getPitch(), mSensor.getRoll());
            //get four corner geo locations
            GeotagActivity gT = new GeotagActivity(dataHolder.getLatLonAlt(), dataHolder.getAzimuth(), dataHolder.getPitch(), dataHolder.getRoll());
            //create four corners holder
            FourCorners fc = new FourCorners(gT.getTopLeft(), gT.getTopRight(), gT.getBottomLeft(), gT.getBottomRight());
            //set four corners
            dataHolder.setFourCorners(fc);
            locked = false;
            this.notify();
        }

Answer 1

试试这个:

Data dataHolder= null;

    lThread.setLocked(true);
    lThread.run();
        while(lThread.isLocked()){

            try {

                Thread.sleep(3000);
            }
            catch(InterruptedException e){

            }
        }
       dataHolder = lThread.dataHolder;

线程2的run方法:

        //get gps data
        LatLongAlt lla = getLatLonAlt();
        if (lla == null) {
            return;
        }
        //create image data holder
        dataHolder = new Data(lla, mSensor.getAzimuth(), -1 * mSensor.getPitch(), mSensor.getRoll());
        //get four corner geo locations
        GeotagActivity gT = new GeotagActivity(dataHolder.getLatLonAlt(), dataHolder.getAzimuth(), dataHolder.getPitch(), dataHolder.getRoll());
        //create four corners holder
        FourCorners fc = new FourCorners(gT.getTopLeft(), gT.getTopRight(), gT.getBottomLeft(), gT.getBottomRight());
        //set four corners
        dataHolder.setFourCorners(fc);
        setLocked(false);
        this.notify();

为锁定创建 getter 和 setter:

public synchronized boolean isLocked() {
    return locked;
}

public synchronized void setLocked(boolean locked) {
    this.locked = locked;
}

基本上，您通过同步 lThread 上的整个进程来永远锁定它。您假设仅同步交互点。