给文本区域加网页背景，文本区域加网页背景,public class

给文本区域加网页背景，文本区域加网页背景,public class

public class BackgroundLoader implements Runnable {        private ScrollPaneWatermark watermark;        public BackgroundLoader(ScrollPaneWatermark watermark) {            this.watermark = watermark;        }           public void run() {            while(true) {            try {                 String base_url = "http://antwrp.gsfc.nasa.gov/apod/";                 URL url = new URL(base_url);                Reader input = new InputStreamReader(url.openStream());                char buf[] = new char[1024];                StringBuffer page_buffer = new StringBuffer();                while(true) {                int n = input.read(buf);                 if(n < 0) { break; }                 page_buffer.append(buf,0,n);            }            // Locate the Image URL (see next section)    Pattern pattern = Pattern.compile("<IMG SRC=\\"(.*)\\"");    Matcher matcher = pattern.matcher(page_buffer);    matcher.find();    String img_url = base_url + matcher.group(1);    watermark.setBackgroundTexture(new URL(img_url));    watermark.repaint();    Thread.currentThread().sleep(1000*60*60*2);             } catch (Exception ex) {                System.out.println("exception: " + ex);                ex.printStackTrace();            }         }     }   }    public static void main(String[] args) throws IOException {         JFrame frame = new JFrame("Blocking Window");         JTextArea jta = new JTextArea(10,40);         jta.setForeground(Color.white);        ScrollPaneWatermark viewport = new ScrollPaneWatermark();        viewport.setView(jta);        viewport.setOpaque(false);        JScrollPane scroll = new JScrollPane();        scroll.setViewport(viewport);        Container comp = frame.getContentPane();        comp.add("Center",scroll);        frame.pack();        frame.show();        new Thread(new BackgroundLoader(viewport)).start(); }//该片段来自于http://byrx.net