Problems with rotating a BufferedImage

Question

I'm trying to rotate an image clockwise and counter clockwise. With the help of this answer from Sri Harsha Chilakapati I managed to get it working according to my needs. This is the code

String rotateURL = tmp_dir + "/" + strusername + "rotate.jpg";
File fileJPG = new File(tmp_dir + "/" + strusername + "FullSize.jpg");
fullImage = ImageIO.read(fileJPG);
leftImage = rotateLeft(fullImage, 90);                      
writeImageToFile(leftImage, "jpg", new File(rotateURL));

public static BufferedImage rotateLeft(BufferedImage img, double angle)
        {
            double sin = Math.abs(Math.sin(Math.toRadians(angle))),
                   cos = Math.abs(Math.cos(Math.toRadians(angle)));

            int w = img.getWidth(null), h = img.getHeight(null);

            int neww = (int) Math.floor(w*cos + h*sin),
                newh = (int) Math.floor(h*cos + w*sin);

            BufferedImage bimg = new BufferedImage(neww, newh, BufferedImage.TYPE_INT_RGB);
            Graphics2D g = bimg.createGraphics();

            g.translate((neww-w)/2, (newh-h)/2);
            g.rotate(Math.toRadians(angle), w/2, h/2);
            g.drawRenderedImage(img, null);
            g.dispose();

            return bimg;
        }

However, I seem to have a caching (not sure about this) problem where I need to put a Thread.sleep(9000);above the fullImage = ImageIO.read(fileJPG); line otherwise my image element would contain the right dimension but doesn't show it rotated. Since a picture says more than a 1000 words:

To be clear, this is how it should look like:

Now the sleep is a solution but to be honest I don't want to wait 9 seconds (counted it, 8 doesn't work) before it rotates. Also, I'm not sure what it gives on a slower computer because it could be possible that it will take longer?

Since AffineTransform quadrantrotate should be more efficient (and the question is marked as duplicate) I tried following answer but the problem still occurs. The code:

    AffineTransform at = new AffineTransform();
    at.translate(100, 40);
    at.quadrantRotate(1, img.getWidth() / 2, img.getHeight() / 2);

    g.drawImage(img, at, null);

    g.dispose();

still gives the same issues. I tried a different approach on reading the image

fullImage = Toolkit.getDefaultToolkit().getImage(new File(rotateURL).getAbsolutePath());
leftImage = rotatePicture(fullImage, 90);

but still the problem remains. So there seems to be a problem with the reading of the image, are there any other ways I didn't think about while reading the image?

Assuming you want to accept a angle which isn't 90, 180, 270 or 0, `neww = (int) Math.floor(w*cos + h*sin)` is not the new width (similarly for height). — Andy Turner, Nov 09 '15 at 13:46
Possible duplicate of [Is there a more efficient way to rotate images in Java than AffineTransform?](http://stackoverflow.com/questions/25826838/is-there-a-more-efficient-way-to-rotate-images-in-java-than-affinetransform) — Andy Turner, Nov 09 '15 at 13:55
You should constrain your angle parameter then. You don't currently stop me rotating by 5 degrees, for example. — Andy Turner, Nov 09 '15 at 13:57
Hmm yeah, didn't thought of that. That however is not the problem right now. I want it working first, then I shall worry about constraints. I don't see why this is a possible duplicate btw. It's about the same endpoint but this question is purely meant for the problem with the dimensions — Noosrep, Nov 09 '15 at 14:03
But if you can constrain it to being 90, 180 etc, you can use `quadrantRotate`, which is much more efficient. — Andy Turner, Nov 09 '15 at 14:04

Problems with rotating a BufferedImage

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