AWT/Swing 中的 Memory 泄漏？

Question

I have a fullscreen overlay with 3 different photos. I'm storing BufferedImage instances in ArrayList, and switch between photos using CardLayout listeneing to KeyEvent s (reacting to pressing arrow keys).

When I test this overlay isolated, it works just fine.

But when I open it as part of my application, I get the following error:

Exception in thread "AWT-EventQueue-0" java.lang.OutOfMemoryError: Java heap space
        at java.awt.image.DataBufferInt.<init>(DataBufferInt.java:75)
        at java.awt.image.Raster.createPackedRaster(Raster.java:467)
        at java.awt.image.DirectColorModel.createCompatibleWritableRaster(DirectColorModel.java:1032)
        at java.awt.image.BufferedImage.<init>(BufferedImage.java:331)
        at sun.java2d.pipe.DrawImage.makeBufferedImage(DrawImage.java:324)
        at sun.java2d.pipe.DrawImage.renderImageXform(DrawImage.java:392)
        at sun.java2d.d3d.D3DDrawImage.renderImageXform(D3DDrawImage.java:77)
        at sun.java2d.pipe.DrawImage.transformImage(DrawImage.java:264)
        at sun.java2d.pipe.DrawImage.scaleImage(DrawImage.java:124)
        at sun.java2d.pipe.DrawImage.scaleImage(DrawImage.java:1046)
        at sun.java2d.pipe.ValidatePipe.scaleImage(ValidatePipe.java:207)
        at sun.java2d.SunGraphics2D.drawImage(SunGraphics2D.java:3127)
        at sun.java2d.SunGraphics2D.drawImage(SunGraphics2D.java:3067)
        at xmessenger.Overlay$ImageViewer.paintComponent(Overlay.java:143)
        at javax.swing.JComponent.paint(JComponent.java:1055)
        at javax.swing.JComponent.paintChildren(JComponent.java:888)
        at javax.swing.JComponent.paint(JComponent.java:1064)
        at javax.swing.JComponent.paintChildren(JComponent.java:888)
        at javax.swing.JComponent.paint(JComponent.java:1064)
        at javax.swing.JComponent.paintChildren(JComponent.java:888)
        at javax.swing.JComponent.paint(JComponent.java:1064)
        at javax.swing.JComponent.paintToOffscreen(JComponent.java:5232)
        at javax.swing.BufferStrategyPaintManager.paint(BufferStrategyPaintManager.java:295)
        at javax.swing.RepaintManager.paint(RepaintManager.java:1249)
        at javax.swing.JComponent._paintImmediately(JComponent.java:5180)
        at javax.swing.JComponent.paintImmediately(JComponent.java:4991)
        at javax.swing.RepaintManager$3.run(RepaintManager.java:808)
        at javax.swing.RepaintManager$3.run(RepaintManager.java:796)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
        at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:796)
        at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:769)

Here is my Overlay class:

public class Overlay extends JFrame {

        public Overlay(ArrayList<BufferedImage> imgs) {
            super();
            this.setUndecorated(true);
            getRootPane().setOpaque(true);
            pane = new JPanel();
            pane.setOpaque(false);
            add(pane);
            pane.setLayout(new CardLayout());

            Dimension dim = Toolkit.getDefaultToolkit().getScreenSize();
            imgWidth = (int) (dim.width * 0.7 + 0.4);
            imgHeight = (int) (imgWidth / 16 * 9 + 0.4);

            pos = 0;

            images = imgs;

            for (BufferedImage image: images) {
                addFrame(image);
            }

            ((CardLayout)pane.getLayout()).first(pane);
            pane.invalidate();

            this.addKeyListener(new KeyListener() {

                @Override
                public void keyTyped(KeyEvent e) {}

                @Override
                public void keyPressed(KeyEvent e) {
                    if (e.getKeyCode() == KeyEvent.VK_ESCAPE) {
                        setVisible(false);
                        dispose();
                    }
                    else if (e.getKeyCode() == KeyEvent.VK_LEFT) {
                        ((CardLayout)pane.getLayout()).previous(pane);
                        pos--;
                        if (pos < 0) pos = images.size() - 1;
                    }
                    else if (e.getKeyCode() == KeyEvent.VK_RIGHT) {
                        ((CardLayout)pane.getLayout()).next(pane);
                        pos++;
                        if (pos > images.size() - 1) pos = 0;
                    }
                }

                @Override
                public void keyReleased(KeyEvent e) {}
            });
        }

        public class ImageViewer extends JPanel {

            public ImageViewer(String src) {
                this.src = src;
                setOpaque(false);
                try {
                    img = ImageIO.read(new URL(src));
                    int imgHeight = img.getHeight(observer);
                    if (imgHeight > 0) {
                        w = (int) (h * ((double) img.getWidth(null) / imgHeight));
                    }
                } catch (IOException ex) {}
            }

            public ImageViewer(BufferedImage image, int width, int height) {
                if (image == null) return;
                setOpaque(false);
                setPreferredSize(new Dimension(width, height));
                setMinimumSize(new Dimension(width, height));
                setMaximumSize(new Dimension(width, height));
                System.out.println(width + "x" +  height);
                w = width;
                h = height;

                img = image;
                int imgHeight = img.getHeight(observer);
                if (imgHeight > 0) {
                    w = (int) (h * ((double) img.getWidth(null) / imgHeight));
                }
            }

            public ImageViewer(String src, int width, int height) {
                setOpaque(false);
                setPreferredSize(new Dimension(width, height));
                setMinimumSize(new Dimension(width, height));
                setMaximumSize(new Dimension(width, height));
                w = width;
                h = height;
                this.src = src;
                try {
                    img = ImageIO.read(new URL(src));
                    int imgHeight = img.getHeight(observer);
                    if (imgHeight > 0) {
                        w = (int) (h * ((double) img.getWidth(null) / imgHeight));
                    }
                } catch (IOException ex) {}
            }

            ImageObserver observer = new ImageObserver() {
                @Override
                public boolean imageUpdate(Image img, int infoflags, int x, int y, int width, int height) {
                    if (height == 0) return false;
                    w = (int) (h * ((double) width / height));
                    if (getParent() != null) getParent().repaint();
                    return true;
                }
            };

            @Override
            public void paintComponent(Graphics g) {
                super.paintComponent(g);
                if (img == null) return;
                Graphics2D g2d = (Graphics2D) g;
                int x = (int) (getWidth() - w) / 2;
                int y = (int) (getHeight() - h) / 2;
                System.out.println(x + ", " + y);
                g2d.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BICUBIC);
                g2d.clearRect(x, y, w, h);
                g2d.drawImage(img, x, y, w, h, null);
            }

            private int w;
            private int h;

            private Image img;
            private String src = null;
        }

        public void addFrame(BufferedImage image) {
            panel = new JPanel();
            panel.setBackground(new Color(12,12,12));

            pane.add(panel);
            panel.setBorder(BorderFactory.createEmptyBorder(90, 90, 90, 90));

            ImageViewer viewer = new ImageViewer(image, imgWidth, imgHeight);
            panel.setLayout(new BorderLayout());
            panel.add(viewer);

            int number = pane.getComponentCount();
            JLabel status = new JLabel(number + " / " + images.size());
            status.setForeground(new Color(235, 235, 235));
            status.setFont(new Font("SegoeUI", Font.PLAIN, 17));
            status.setHorizontalAlignment(SwingConstants.CENTER);
            panel.add(status, BorderLayout.PAGE_END);
        }

        public void prevImage() {
            ((CardLayout)pane.getLayout()).previous(pane);
            pos--;
            if (pos < 0) pos = images.size() - 1;
        }

        public void nextImage() {
            ((CardLayout)pane.getLayout()).next(pane);
            pos++;
            if (pos > images.size() - 1) pos = 0;
        }

        private int imgWidth = 0;
        private int imgHeight = 0;

        private ArrayList<BufferedImage> images;
        private int pos = 0;

        public void showContent() {
            try {
                GraphicsEnvironment.getLocalGraphicsEnvironment().getDefaultScreenDevice().setFullScreenWindow(this);
                setVisible(true);
            } catch (Exception error) {}
        }

        public static void main(String[] args) {
            ArrayList<BufferedImage> images = new ArrayList<BufferedImage>();
            try {
                images.add(ImageIO.read(new File("D:/My Documents/NetBeansProjects/XMessenger/image.jpg")));
                images.add(ImageIO.read(new URL("http://popov654.pp.ru/copybox/photo.jpg")));
                images.add(ImageIO.read(new URL("http://popov654.pp.ru/copybox/DSCN2155.jpg")));
            } catch (IOException ex) {}
            Overlay o = new Overlay(images);
            o.showContent();
        }

        JPanel pane;
        JPanel panel;
    }

If I run it, it works OK. The problem appears when I create an instance from outside code:

   private void addHyperlinkListener(JTextPane pane) {
        pane.addHyperlinkListener(new HyperlinkListener() {
            @Override
            public void hyperlinkUpdate(HyperlinkEvent e) {
                if (e.getEventType() == HyperlinkEvent.EventType.ACTIVATED) {
                    String src = (String) e.getSourceElement().getAttributes().getAttribute(HTML.Attribute.SRC);
                    System.err.println("Image src: " + src);
                    HTMLDocument doc = (HTMLDocument) msgContent.getStyledDocument();
                    Element[] imgs = getElementsByTagName(HTML.Tag.IMG, doc);

                    ArrayList<BufferedImage> images = new ArrayList<BufferedImage>();
                    ArrayList<String> srcs = new ArrayList<String>();
                    
                    int index = -1;
                    for (Element img: imgs) {
                        String source = (String) img.getAttributes().getAttribute(HTML.Attribute.SRC);
                        srcs.add(source);
                        try {
                            images.add(ImageIO.read(new URL(source)));
                        } catch (IOException ex) {}
                        if (!source.equals(src) && index < 0) {
                            index++;
                        }
                    }
                    
                    Overlay overlay = new Overlay(images);
                    for (int i = 0; i < index; i++) {
                        overlay.nextImage();
                    }
                    XMessengerApp.getMainWindow().getFrame().setVisible(false);
                    overlay.showContent();
                    
                }
            }
        });
    }

By the way, if I don't hide my current application frame, it keeps blinking through some areas of my overlay, which is also very strange. I thought that is the reason of failure (too many repaints because of that thing), but hiding it from the screen also does not help to avoid the errors.

Also when iI encounter this error, the blocks in my overlay's CardLayout stop reacting to key presses at all.

What am I doing wrong?

The application is not very heavy, the most "big" part of it is a JTextPane with HTML content, but that is ridiculously small: one 2-line paragraph of text and 3 images after it.

The app is made using the JDesktop framework. I'm running the code with JDK 7.

Also look here, please:

https://bugs.java.com/bugdatabase/view_bug.do?bug_id=6567435 https://www.codeproject.com/Questions/5311994/How-to-fix-a-memory-leak-caused-by-bufferedimage-g

Maybe there is a bug leading to this in JDK/JRE? Except I am reading JPEGs, and not TIFFs, but with a much similar resolution.

Answer 1

The solution is to increase the heap size for the VM:

-Xmx512m