camstatehelper.java

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package jp.sourceforge.qrcode.example.jmf;

   import javax.media.*;

   public class camStateHelper implements javax.media.ControllerListener {
       
       Player player = null;
       boolean configured = false;
       boolean realized = false;
       boolean prefetched = false;
       boolean eom = false;
       boolean failed = false;
       boolean closed = false;
       
       public camStateHelper(Player p) {
           player = p;
           p.addControllerListener(this);
       }
       
       public boolean configure(int timeOutMillis) {
           
           long startTime = System.currentTimeMillis();
           synchronized (this) {
               if (player instanceof Processor)
                   ((Processor)player).configure();
               else
                   return false;
               while (!configured && !failed) {
                   try {
                       wait(timeOutMillis);
                   } catch (InterruptedException ie) {
                   }
                   if (System.currentTimeMillis() - startTime > timeOutMillis)
                       break;
               }
           }
           return configured;
       }
       
       public boolean realize(int timeOutMillis) {
           long startTime = System.currentTimeMillis();
           synchronized (this) {
               player.realize();
               while (!realized && !failed) {
                   try {
                       wait(timeOutMillis);
                   }catch (InterruptedException ie) {
                   }
                   if (System.currentTimeMillis() - startTime > timeOutMillis)
                       break;
               }
           }
           return realized;
       }
       
       public boolean prefetch(int timeOutMillis) {
           long startTime = System.currentTimeMillis();
           synchronized (this) {
               player.prefetch();
               while (!prefetched && !failed) {
                   try {
                       wait(timeOutMillis);
                   }catch (InterruptedException ie) {
                   }
                   if (System.currentTimeMillis() - startTime > timeOutMillis)
                       break;
               }
           }
           return prefetched && !failed;
       }
       public boolean playToEndOfMedia(int timeOutMillis) {
           long startTime = System.currentTimeMillis();
           eom = false;
           synchronized (this) {
               player.start();
               while (!eom && !failed) {
                   try {
                       wait(timeOutMillis);
                   }catch (InterruptedException ie) {
                   }
                   if (System.currentTimeMillis() - startTime > timeOutMillis)
                       break;
               }
           }
           return eom && !failed;
       }
       
       public void close() {
           synchronized (this) {
               player.close();
               while (!closed) {
                   try {
                       wait(100);
                   } catch (InterruptedException ie) {
                   }
               }
           }
           player.removeControllerListener(this);
       }
       
       public synchronized void controllerUpdate(ControllerEvent ce) {
           if (ce instanceof RealizeCompleteEvent) {
               realized = true;
           }else if (ce instanceof ConfigureCompleteEvent) {
               configured = true;
           } else if (ce instanceof PrefetchCompleteEvent) {
               prefetched = true;
           } else if (ce instanceof EndOfMediaEvent) {
               eom = true;
           } else if (ce instanceof ControllerErrorEvent) {
               failed = true;
           } else if (ce instanceof ControllerClosedEvent) {
               closed = true;
           } else {
               return;
           }
           notifyAll();
       }
   }