package bluej;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import bluej.pkgmgr.Project;
import threadchecker.OnThread;
import threadchecker.Tag;




| Class to handle (throw and deliver) BlueJ events. Event are defined
| for things that might be caused by low level parts of the system which
| other parts of the system might be interested in. Objects can register
| themselves as event listeners. They then get notified of events.
|
| <p>A BlueJEvent has one argument. The argument passed differs for every
| event type.
|
| <p>Event types and their arguments:<PRE>
|
|  Type               argument            sent when...
|  -----------------------------------------------------------------------
|  CREATE_VM          (unused)            creation of VM has started
|
|  CREATE_VM_FAILED   (unused)            creation of VM has failed
|
|  CREATE_VM_DONE     (unused)            creation of VM completed
|
|  METHOD_CALL        InvokerRecord       an interactive method call was started
|
|  EXECUTION_RESULT   bluej.debugmgr.ExecutionEvent   VM execution finished
|
|  GENERATING_DOCU    (unused)            documentation generation started
|
|  DOCU_GENERATED     (unused)            documentation generation finished
|
|  DOCU_ABORTED       (unused)            documentation generation aborted
|
| </PRE>
|
| @author Michael Kolling
|
public class BlueJEvent
{       


   
   public static final int CREATE_VM           = 0;
   
   public static final int CREATE_VM_FAILED    = CREATE_VM + 1;
   
   public static final int CREATE_VM_DONE      = CREATE_VM_FAILED + 1;
   
   public static final int METHOD_CALL         = CREATE_VM_DONE + 1;
   
   public static final int METHOD_CALL_FAILED  = METHOD_CALL + 1;
   
   public static final int EXECUTION_RESULT    = METHOD_CALL_FAILED + 1;
   
   public static final int GENERATING_DOCU     = EXECUTION_RESULT + 1;
   
   public static final int DOCU_GENERATED      = GENERATING_DOCU + 1;
   
   public static final int DOCU_ABORTED        = DOCU_GENERATED + 1;
    
   
   

   @OnThread(Tag.Any)
   
   private static List<BlueJEventListener> listeners =
       
   Collections.synchronizedList(new ArrayList<BlueJEventListener>());

   
   


| Raise a BlueJ event with an argument. All registered listeners
| will be informed of this event.
|
@OnThread(Tag.FXPlatform)
   
   public static void raiseEvent(int eventId, Object arg)
   {
      Object[] listenersCopy = listeners.toArray();
       
      for (int i = listenersCopy.length - 1; i >= 0; i--) {
         BlueJEventListener listener = (BlueJEventListener) listenersCopy[i];
         listener.blueJEvent(eventId, arg, null);         
         }     
      }

   
   


| Raise a BlueJ event with an argument and a reference to the project where the event is raised.
| All registered listeners will be informed of this event.
|
@OnThread(Tag.FXPlatform)
   
   public static void raiseEvent(int eventId, Object arg, Project prj)
   {
      Object[] listenersCopy = listeners.toArray();
       
      for (int i = listenersCopy.length - 1; i >= 0; i--) {
         BlueJEventListener listener = (BlueJEventListener) listenersCopy[i];
         listener.blueJEvent(eventId, arg, prj);         
         }     
      }
    
   
   


| Add a listener object. The object must implement the
| BlueJEventListener interface.
|
@OnThread(Tag.Any)
   
   public static void addListener(BlueJEventListener listener)
   {
      if (!listeners.contains(listener))
      listeners.add(listener);     
      }
    
   
   


| Remove a listener object from the known listener set.
|
@OnThread(Tag.Any)
   
   public static void removeListener(BlueJEventListener listener)
   {
      listeners.remove(listener);     
      }      
   }