Create a Custom Callback Handler

import com.sybase.persistence.DefaultCallbackHandler;
……
public class Test
{
   public static void main(String[] args)
   {
      SMP101DB.registerCallbackHandler(new MyCallbackHandler());
      GenericList<SynchronizationGroup> sgs = new GenericList<SynchronizationGroup>();
      sgs.add(SMP101DB.getSynchronizationGroup("sg1"));
      sgs.add(SMP101DB.getSynchronizationGroup("sg2"));
      SMP101DB.beginSynchronize(sgs, "my test synchronization context");
   }
}

class MyCallbackHandler extends DefaultCallbackHandler
{
   //The onSynchronize method overrides the 
   //onSynchronize method from DefaultCallbackHandler.  
   public int onSynchronize(GenericList<SynchronizationGroup> groups, SynchronizationContext context)
   {
      if ( context == null )
      {
         return SynchronizationAction.CANCEL;
      }

      if (!("my test synchronization context".equals((String)(context.getUserContext()))))
      {
         return super.onSynchronize(groups, context);
      }

      switch (context.getStatus())
      // The application is waiting for input from the user. 
      // This section demonstrates that you can stop the synchronization or 
      // let it proceed depending on the status of the application.
      {
         case SynchronizationStatus.STARTING:
            if (waitForMoreChanges())
            {
               return SynchronizationAction.CANCEL;
            }
            else
            {
               return SynchronizationAction.CONTINUE;
            }
         default:
            return SynchronizationAction.CONTINUE;
      }
   }
}