Parhelion (2007)

MainCode (){
//        1. Create the frame.
        super("FrameDemo");
        this.setPreferredSize(new Dimension (800,600));
        this.setBackground(Color.BLACK);
        this.setUndecorated(true);
       
//        2. Optional: What happens when the frame closes?
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

//        3. Create components and put them in the frame.
        // ---------------------------------------------------------------------
        // Get the image from the URL
        // ---------------------------------------------------------------------
        imagePanel = new ImagePanel();
        Container contentPane = this.getContentPane();
        contentPane.setLayout(new GridBagLayout());
        
        GridBagConstraints gc = new GridBagConstraints();
        gc.gridx = 0; gc.gridy = 0;
        gc.anchor = GridBagConstraints.CENTER;
        imagePanel.setPreferredSize(new Dimension(600,600));
        contentPane.setBackground(Color.BLACK);
        contentPane.add(imagePanel, gc);

        contentPane.setLayout(new BorderLayout());
        contentPane.add(imagePanel, BorderLayout.CENTER);
        
//        4. Size the frame.
        this.pack();
    }

    private Image makeImage(String filename) {
        BufferedImage image = null;
       
        try {
            if (filename.contains("http")) {
                URL url = new URL(filename);
                image = ImageIO.read(url);
            }
            else {
                File file = new File(filename);
                image = ImageIO.read(file);                
            }
        } catch (MalformedURLException e) {
            // count attempt stuff should go in IOException handling...*if* filename contains "http"
            // this exception just catches malformed urls, not the connection failure we saw before
            /*countAttempt++;
            System.err.println(filename + "; count attempt = " + countAttempt);
            if (countAttempt < 4) {
                System.err.println("retry this url");
                return makeImage(filename); // retry this url a few times...
            }
            else {
                System.err.println("try archive image instead");*/
                return makeImage(selector.requestArchiveImage()); //...but not forever. try an archive image instead
            /*}*/
            //e.printStackTrace();
        } catch (IOException e) {
            //System.err.println(filename + "; count attempt = " + countAttempt);
            //System.err.println("using different archive image");
               return makeImage(selector.requestArchiveImage()); // try a different archive image
            //e.printStackTrace();
        }
        
        //return Toolkit.getDefaultToolkit().createImage(url);
        //countAttempt = 0; //reset countAttempt if we get this far
        return image.getScaledInstance(600, 600, Image.SCALE_AREA_AVERAGING);
    }
    
    private void changeImage (ImageSelector selector){
        this.selector = selector; // remember this as a class level variable for error handling
        Image currentImage = null;
       
        while(true) {
            if (currentImage == null) {
                imagePanel.setImage1(makeImage(selector.getImageName()));
            }
            else {
                imagePanel.setImage1(currentImage);
            }
            currentImage = makeImage(selector.getNextImageName());
            imagePanel.setImage2(currentImage);

            for (int i=0; i<201; i++){
                imagePanel.setAlpha(i*0.005F); //1/200 iterations = .5% opacity
                this.repaint();

                try {
                    Thread.sleep(500); //.5 second iteration for alpha change
                } catch (InterruptedException e) {
                    // for now do nothing if sleep didn't work
                    //e.printStackTrace();
                }            
            }

            try {
                Thread.sleep(10000); // 10 seconds
            } catch (InterruptedException e) {
                // for now do nothing if sleep didn't work
                //e.printStackTrace();
            }            

        } //uncomment this and the first line, comment the last...this will switch from tail-recursion to iteration
        //changeImage(selector); //comment above line and first, uncomment this to switch to tail-recursion
    }
    
    public static void main(String[] args) {
        MainCode mainFrame = new MainCode();
        mainFrame.setVisible(true);
        
        mainFrame.changeImage(new ImageSelector());
    }