src/jalview/javascript/JSFunctionExec.java

   1 package jalview.javascript;
   2
   3 import java.net.URL;
   4 import java.util.Vector;
   5
   6 import netscape.javascript.JSException;
   7 import netscape.javascript.JSObject;
   8 import jalview.bin.JalviewLite;
   9
  10 public class JSFunctionExec implements Runnable
  11 {
  12   JalviewLite jvlite;
  13
  14   public JSFunctionExec(JalviewLite applet)
  15   {
  16     jvlite = applet;
  17   }
  18
  19   private static Vector jsExecQueue;
  20
  21   private static Thread executor = null;
  22
  23   public static void stopQueue()
  24   {
  25     if (jsExecQueue != null)
  26     {
  27       Vector q = jsExecQueue;
  28       jsExecQueue = null;
  29       q.removeAllElements();
  30       executor.notify();
  31       executor = null;
  32     }
  33   }
  34
  35   public void run()
  36   {
  37     while (jsExecQueue != null)
  38     {
  39       if (jsExecQueue.size() > 0)
  40       {
  41         Runnable r = (Runnable) jsExecQueue.elementAt(0);
  42         jsExecQueue.removeElementAt(0);
  43         try
  44         {
  45           r.run();
  46         } catch (Exception ex)
  47         {
  48           ex.printStackTrace();
  49         } catch (Error ex)
  50         {
  51           ex.printStackTrace();
  52         }
  53       }
  54       else
  55       {
  56         try
  57         {
  58           synchronized (jsExecQueue)
  59           {
  60             jsExecQueue.wait(1000);
  61           }
  62         } catch (Exception ex)
  63         {
  64         }
  65         ;
  66       }
  67     }
  68
  69   }
  70
  71   /**
  72    * execute a javascript callback asynchronously
  73    *
  74    * @param _listener
  75    * @param objects
  76    * @throws Exception
  77    */
  78   public void executeJavascriptFunction(final String _listener,
  79           final Object[] objects) throws Exception
  80   {
  81     executeJavascriptFunction(false, _listener, objects);
  82   }
  83
  84   /**
  85    * execute a javascript callback synchronously or asynchronously
  86    *
  87    * @param async
  88    *          - true to execute asynchronously (do this for gui events)
  89    * @param _listener
  90    *          - javascript function
  91    * @param objects
  92    *          - arguments
  93    * @throws Exception
  94    *           - only if call is synchronous
  95    */
  96   public void executeJavascriptFunction(final boolean async,
  97           final String _listener, Object[] arguments) throws Exception
  98   {
  99     final Object[] objects = new Object[arguments != null ? arguments.length
 100             : 0];
 101     if (arguments != null)
 102     {
 103       System.arraycopy(arguments, 0, objects, 0, arguments.length);
 104     }
 105     final Exception[] jsex = new Exception[1];
 106     Runnable exec = new Runnable()
 107     {
 108       public void run()
 109       {
 110         try
 111         {
 112           JSObject scriptObject = null;
 113           try
 114           {
 115             scriptObject = JSObject.getWindow(jvlite.applet);
 116           } catch (Exception ex)
 117           {
 118           }
 119           ;
 120           if (scriptObject != null)
 121           {
 122             scriptObject.call(_listener, objects);
 123           }
 124         } catch (Exception jex)
 125         {
 126           // squash any malformedURLExceptions thrown by windows/safari
 127           if (!(jex instanceof java.net.MalformedURLException))
 128           {
 129             if (jvlite.debug)
 130             {
 131               System.err.println(jex);
 132             }
 133             if (jex instanceof netscape.javascript.JSException)
 134             {
 135               jsex[0] = (netscape.javascript.JSException) jex;
 136               if (jvlite.debug)
 137               {
 138                 System.err.println("Falling back to javascript: url call");
 139               }
 140               StringBuffer sb = new StringBuffer("javascript:" + _listener
 141                       + "(");
 142               for (int i = 0; objects != null && i < objects.length; i++)
 143               {
 144                 if (i > 0)
 145                 {
 146                   sb.append(",");
 147                 }
 148                 sb.append("\"");
 149                 // strip out nulls and complex objects that we can't pass this
 150                 // way.
 151                 if (objects[i] != null
 152                         && !(objects[i].getClass().getPackage().getName()
 153                                 .indexOf("jalview") == 0))
 154                 {
 155                   sb.append(objects[i].toString());
 156                 }
 157                 sb.append("\"");
 158               }
 159               sb.append(")");
 160               if (jvlite.debug)
 161               {
 162                 System.err.println(sb.toString());
 163               }
 164               // alternate
 165               URL url = null;
 166               try
 167               {
 168                 url = new URL(sb.toString());
 169                 jvlite.getAppletContext().showDocument(url);
 170                 jex = null;
 171               } catch (Exception uex)
 172               {
 173                 jex = uex;
 174               }
 175             }
 176             if (jex != null)
 177             {
 178               if (async)
 179               {
 180                 jex.printStackTrace();
 181               }
 182               else
 183               {
 184                 jsex[0] = new Exception(jex);
 185               }
 186             }
 187             ;
 188           }
 189
 190         }
 191       }
 192     };
 193     if (async)
 194     {
 195       if (JSFunctionExec.executor == null)
 196       {
 197         JSFunctionExec.jsExecQueue = new Vector();
 198         JSFunctionExec.executor = new Thread(new JSFunctionExec(jvlite));
 199         executor.start();
 200       }
 201       synchronized (jsExecQueue)
 202       {
 203         jsExecQueue.addElement(exec);
 204         jsExecQueue.notify();
 205       }
 206     }
 207     else
 208     {
 209       exec.run();
 210       if (jsex[0] != null)
 211       {
 212         throw (jsex[0]);
 213       }
 214     }
 215   }
 216
 217 }