Rotate an image in java

You need to be using trigonometry to determine the correct width/height, using transparency to prevent the black area, and I think the Transform is wrong, which is making it off center.

Try this:

public static BufferedImage rotate(BufferedImage image, double angle) {
    double sin = Math.abs(Math.sin(angle)), cos = Math.abs(Math.cos(angle));
    int w = image.getWidth(), h = image.getHeight();
    int neww = (int)Math.floor(w*cos+h*sin), newh = (int) Math.floor(h * cos + w * sin);
    GraphicsConfiguration gc = getDefaultConfiguration();
    BufferedImage result = gc.createCompatibleImage(neww, newh, Transparency.TRANSLUCENT);
    Graphics2D g = result.createGraphics();
    g.translate((neww - w) / 2, (newh - h) / 2);
    g.rotate(angle, w / 2, h / 2);
    g.drawRenderedImage(image, null);
    g.dispose();
    return result;
}

private static GraphicsConfiguration getDefaultConfiguration() {
    GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
    GraphicsDevice gd = ge.getDefaultScreenDevice();
    return gd.getDefaultConfiguration();
}

from http://flyingdogz.wordpress.com/2008/02/11/image-rotate-in-java-2-easier-to-use/

Based on a previous example, but actually working with recent JDKs and in headless mode:

public static BufferedImage rotate(BufferedImage image, double angle) {
    double sin = Math.abs(Math.sin(angle)), cos = Math.abs(Math.cos(angle));
    int w = image.getWidth(), h = image.getHeight();
    int neww = (int)Math.floor(w*cos+h*sin), newh = (int) Math.floor(h * cos + w * sin);
    BufferedImage result = deepCopy(image, false);
    Graphics2D g = result.createGraphics();
    g.translate((neww - w) / 2, (newh - h) / 2);
    g.rotate(angle, w / 2, h / 2);
    g.drawRenderedImage(image, null);
    g.dispose();
    return result;
}

public static BufferedImage deepCopy(BufferedImage bi, boolean copyPixels) {
    ColorModel cm = bi.getColorModel();
    boolean isAlphaPremultiplied = cm.isAlphaPremultiplied();
    WritableRaster raster = bi.getRaster().createCompatibleWritableRaster();
    if (copyPixels) {
        bi.copyData(raster);
    }
    return new BufferedImage(cm, raster, isAlphaPremultiplied, null);
}    

You could try using a Rotated Icon.