RuntimeListener.java

package org.jactr.tools.shell;

/*
 * default logging
 */
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.jactr.core.concurrent.ExecutorServices;
import org.jactr.core.runtime.ACTRRuntime;
import org.jactr.core.runtime.event.ACTRRuntimeAdapter;
import org.jactr.core.runtime.event.ACTRRuntimeEvent;
import org.jactr.core.runtime.event.IACTRRuntimeListener;

public class RuntimeListener extends ACTRRuntimeAdapter
{
  /**
   * Logger definition
   */
  static private final transient Log LOGGER   = LogFactory
                                                  .getLog(RuntimeListener.class);

  static private RuntimeListener     _default = null;

  static public void setEnabled(boolean enable)
  {
    synchronized (RuntimeListener.class)
    {
      if (!enable && _default != null)
      {
        if (LOGGER.isDebugEnabled()) LOGGER.debug("Removing runtime listener");
        /*
         * remove and null
         */
        ACTRRuntime.getRuntime().removeListener(_default);
        _default = null;
      }
      else if (enable && _default == null)
      {
        if (LOGGER.isDebugEnabled())
          LOGGER.debug("Installing runtime listener");
        _default = new RuntimeListener();
        ACTRRuntime.getRuntime().addListener(_default,
            ExecutorServices.INLINE_EXECUTOR);
      }
    }
  }

  static public boolean isEnabled()
  {
    synchronized (RuntimeListener.class)
    {
      return _default != null;
    }
  }

  public void runtimeResumed(ACTRRuntimeEvent event)
  {
    try
    {
      Controller.getInterpreter().set("runState", "[running]");
    }
    catch (Exception e)
    {

    }
  }

  /**
   * when called, this makes "runtime" variable accessible
   * 
   * @param event
   * @see org.jactr.core.runtime.event.IACTRRuntimeListener#runtimeStarted(org.jactr.core.runtime.event.ACTRRuntimeEvent)
   */
  public void runtimeStarted(ACTRRuntimeEvent event)
  {
    try
    {
      if (LOGGER.isDebugEnabled()) LOGGER.debug("Making runtime available");
      Controller.getInterpreter().set("runtime", event.getSource());
      if (event.getSource().getModels().size() == 1)
        Controller.getInterpreter().eval(
            "use(\"" + event.getSource().getModels().iterator().next() + "\")");

      Controller.getInterpreter().set("runState", "[running]");
    }
    catch (Exception e)
    {
      /**
       * Error : error
       */
      LOGGER.error("Could not set runtime context : ", e);
    }
  }

  /**
   * when executed blocks the runtime entirely, preventing disposal until quit
   * is called
   * 
   * @param event
   * @see org.jactr.core.runtime.event.IACTRRuntimeListener#runtimeStopped(org.jactr.core.runtime.event.ACTRRuntimeEvent)
   */
  public void runtimeStopped(ACTRRuntimeEvent event)
  {
    if (LOGGER.isDebugEnabled())
      LOGGER.debug("Blocking until Controller.quit() is called");
    try
    {
      Controller.getInterpreter().set("runState", "[stopped]");
    }
    catch (Exception e)
    {

    }
    Controller.block();
  }

  public void runtimeSuspended(ACTRRuntimeEvent event)
  {
    // TODO Auto-generated method stub
    try
    {
      Controller.getInterpreter().set("runState", "[suspended]");
    }
    catch (Exception e)
    {

    }
  }

}