import edu.stanford.ejalbert.exception.UnsupportedOperatingSystemException; //导入依赖的package包/类
/**
 * Konstruktor
 */
public OSMCreditPanel() {
         
   super(new FlowLayout(FlowLayout.CENTER));
   JLabel lab = new JLabel("Map data \u00a9 ");
   lab.setFont(font);
   lab.setForeground(new Color(0x505050));
   add(lab);
             
   lab = new JLabel("OpenStreetMap");
   lab.setCursor(new Cursor(Cursor.HAND_CURSOR));
   Map<TextAttribute, Integer> fontAttr = new HashMap<>();
   fontAttr.put(TextAttribute.UNDERLINE, TextAttribute.UNDERLINE_ON);
   lab.setFont(font.deriveFont(fontAttr));
   lab.setForeground(new Color(0x330066));
   add(lab);
             
   lab.addMouseListener(new MouseAdapter() {
     @Override
     public void mouseClicked(MouseEvent e) {
       try {
          new BrowserLauncher().openURLinBrowser("http://www.openstreetmap.org/copyright");
       }  catch (BrowserLaunchingInitializingException | UnsupportedOperatingSystemException ex) {
          System.err.println(ex);
       }
     }
   });                
             
   lab = new JLabel(" contributors");
   lab.setFont(font);
   lab.setForeground(new Color(0x505050));
   add(lab);                
             
   setBackground(new Color(210, 210, 210, 170));
   setOpaque(true);
   setPreferredSize(new Dimension(270, 24));            

         
}
 

import edu.stanford.ejalbert.exception.UnsupportedOperatingSystemException; //导入依赖的package包/类
/**
 * Return the BrowserLauncher instance
 * @return BrowserLauncher instance
 */
static edu.stanford.ejalbert.BrowserLauncher getLauncher() {
    if (_launcher == null) {
        boolean hackMRJ = false;
        if (SystemUtils.IS_OS_MAC_OSX) {
            // Circumvent BrowserLauncher NPE when running under Oracle 1.7u4 (and later ???) release for Mac OS X
            if (System.getProperty(PROP_MRJ_VERSION) == null) {
                hackMRJ = true;
                System.setProperty(PROP_MRJ_VERSION, "9999.999");
                _logger.debug("Probably running Oracle JVM under Mac OS X, faking missing 'mrj.version' system property.");
            }
        }
        try {
            final LoggerAdapter loggerAdapter = new LoggerAdapter();

            _launcher = new edu.stanford.ejalbert.BrowserLauncher(loggerAdapter, loggerAdapter);

            // Refresh the system property at startup:
            refreshBrowserPref();

        } catch (UnsupportedOperatingSystemException uose) {
            _logger.warn("Cannot initialize browser launcher : ", uose);
        } catch (BrowserLaunchingInitializingException bie) {
            _logger.warn("Cannot initialize browser launcher : ", bie);
        } finally {
            if (hackMRJ) {
                // Circumvent BrowserLauncher NPE when running under Oracle 1.7u4 (and later ???) release for Mac OS X
                System.clearProperty(PROP_MRJ_VERSION);
            }
        }
    }
    return _launcher;
}