Package ucar.util

Class ListenerManager

  • @ThreadSafe
public class ListenerManager
extends Object
    Helper class for managing event listeners. It is thread safe, but better not to be adding/deleting listeners while sending events. LOOK Probably could replace with guava eventbus Example: 
    
  private void createListenerManager() {
    lm = new ListenerManager(
            "ucar.nc2.util.DatasetCollectionManager$EventListener",
            "ucar.nc2.util.DatasetCollectionManager$Event",
            "setMessage");
  }

  public void addEventListener(EventListener l) {
    lm.addListener(l);
  }

  public void removeEventListener(EventListener l) {
    lm.removeListener(l);
  }

  public class Event extends java.util.EventObject {
    private String message;

    Event(String message) {
      super(DatasetCollectionManager.this);
      this.message = message;
    }

    public String getMessage() {
      return message;
    }
  }

  public static interface EventListener {
    public void setMessage(DatasetCollectionManager.Event event);
  }

 lm.sendEvent(event);

    • Constructor Detail

      • ListenerManager

        public ListenerManager​(String listener_class,
                       String event_class,
                       String method_name)
        Constructor.
        Parameters:
        listener_class - the name of the EventListener class, eg "ucar.unidata.ui.UIChangeListener"
        event_class - the name of the Event class, eg "ucar.unidata.ui.UIChangeEvent"
        method_name - the name of the EventListener method, eg "processChange". 
                                  This method must have the signature     public void method_name( event_class e)

    • Method Detail

      • setEnabled

        public void setEnabled​(boolean enabled)

      • getEnabled

        public boolean getEnabled()

      • addListener

        public void addListener​(Object l)
        Add a listener.
        Parameters:
        l - listener must be of type "listener_class"

      • removeListener

        public void removeListener​(Object l)
        Remove a listener.
        Parameters:
        l - listener must be of type "listener_class"

      • hasListeners

        public boolean hasListeners()

      • sendEvent

        public void sendEvent​(EventObject event)
        Send an event to all registered listeners. If an exception is thrown, remove the Listener from the list
        Parameters:
        event - the event to be sent: public void method_name( event_class event)

      • sendEventExcludeSource

        public void sendEventExcludeSource​(EventObject event)
        Send an event to all registered listeners, except the named one.
        Parameters:
        event - the event to be sent: public void method_name( event_class event)