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
 100     executeJavascriptFunction(async, _listener, arguments, null);
 101
 102   }
 103
 104   public void executeJavascriptFunction(final boolean async,
 105           final String _listener, Object[] arguments, final String dbgMsg)
 106           throws Exception
 107   {
 108     final Object[] objects = new Object[arguments != null ? arguments.length
 109             : 0];
 110     if (arguments != null)
 111     {
 112       System.arraycopy(arguments, 0, objects, 0, arguments.length);
 113     }
 114     final Exception[] jsex = new Exception[1];
 115     Runnable exec = new Runnable()
 116     {
 117       public void run()
 118       {
 119         try
 120         {
 121           JSObject scriptObject = null;
 122           try
 123           {
 124             scriptObject = JSObject.getWindow(jvlite);
 125           } catch (Exception ex)
 126           {
 127           }
 128           ;
 129           if (scriptObject != null)
 130           {
 131             if (jvlite.debug && dbgMsg != null)
 132             {
 133               System.err.println(dbgMsg);
 134             }
 135             scriptObject.call(_listener, objects);
 136           }
 137         } catch (Exception jex)
 138         {
 139           // squash any malformedURLExceptions thrown by windows/safari
 140           if (!(jex instanceof java.net.MalformedURLException))
 141           {
 142             if (jvlite.debug)
 143             {
 144               System.err.println(jex);
 145             }
 146             if (jex instanceof netscape.javascript.JSException)
 147             {
 148               jsex[0] = (netscape.javascript.JSException) jex;
 149               if (jvlite.debug)
 150               {
 151                 System.err.println("Falling back to javascript: url call");
 152               }
 153               StringBuffer sb = new StringBuffer("javascript:" + _listener
 154                       + "(");
 155               for (int i = 0; objects != null && i < objects.length; i++)
 156               {
 157                 if (i > 0)
 158                 {
 159                   sb.append(",");
 160                 }
 161                 sb.append("\"");
 162                 // strip out nulls and complex objects that we can't pass this
 163                 // way.
 164                 if (objects[i] != null
 165                         && !(objects[i].getClass().getName()
 166                                 .indexOf("jalview") == 0))
 167                 {
 168                   sb.append(objects[i].toString());
 169                 }
 170                 sb.append("\"");
 171               }
 172               sb.append(")");
 173               if (jvlite.debug)
 174               {
 175                 System.err.println(sb.toString());
 176               }
 177               // alternate
 178               URL url = null;
 179               try
 180               {
 181                 url = new URL(sb.toString());
 182                 jvlite.getAppletContext().showDocument(url);
 183                 jex = null;
 184               } catch (Exception uex)
 185               {
 186                 jex = uex;
 187               }
 188             }
 189             if (jex != null)
 190             {
 191               if (async)
 192               {
 193                 jex.printStackTrace();
 194               }
 195               else
 196               {
 197                 jsex[0] = jex;
 198               }
 199             }
 200             ;
 201           }
 202
 203         }
 204       }
 205     };
 206     if (async)
 207     {
 208       if (JSFunctionExec.executor == null)
 209       {
 210         JSFunctionExec.jsExecQueue = new Vector();
 211         JSFunctionExec.executor = new Thread(new JSFunctionExec(jvlite));
 212         executor.start();
 213       }
 214       synchronized (jsExecQueue)
 215       {
 216         jsExecQueue.addElement(exec);
 217         jsExecQueue.notify();
 218       }
 219     }
 220     else
 221     {
 222       exec.run();
 223       if (jsex[0] != null)
 224       {
 225         throw (jsex[0]);
 226       }
 227     }
 228   }
 229
 230 }