Make thread-safe.

1 files changed, 117 insertions, 107 deletions

diff --git a/java/util/Observable.java b/java/util/Observable.java
index 681cbf6ca..1a57865ed 100644
--- a/java/util/Observable.java
+++ b/java/util/Observable.java
@@ -1,117 +1,127 @@
-/**
- * Observable.java
- *
- * Extended when an object wants to be Observable.
- *
- * @author Daniel Rall (<a href="mailto:dlr@west.net">dlr@west.net</a>, <a href="http://www.finemaltcoding.com/">Fine Malt Coding</a>)
- * @version 1.0b
- */
+/* java.util.Observable
+   Copyright (C) 1999, 2000 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+ 
+GNU Classpath is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+02111-1307 USA.
+
+As a special exception, if you link this library with other files to
+produce an executable, this library does not by itself cause the
+resulting executable to be covered by the GNU General Public License.
+This exception does not however invalidate any other reasons why the
+executable file might be covered by the GNU General Public License. */
 
-/////////////////////////////////////////////////////////////////////////////
-// This program is free software; you can redistribute it and/or modify
-// it under the terms of the GNU Library General Public License as published
-// by the Free Software Foundation, version 2. (see COPYING.LIB)
-//
-// This program is distributed in the hope that it will be useful, but
-// WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Library General Public License for more details.
-//
-// You should have received a copy of the GNU Library General Public License
-// along with this program; if not, write to the Free Software Foundation
-// Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307 USA
-/////////////////////////////////////////////////////////////////////////////
 
 package java.util;
 
 public class Observable
 {
-	private static final short INITIAL_SIZE = 4;
-	
-	private boolean changed;
-	private Vector observers;
-	
-	/**
-	 * Constructs an Observable with 0 Observers.  A resizable buffer is used to
-	 * store Observer references, and is initialized to a small capacity.
-	 */
-	public Observable()
-	{
-		changed = false;
-		observers = new Vector(INITIAL_SIZE);
-	}
+  private boolean changed;
+  private Vector observers;
 	
-	/**
-	 * Adds an Observer. Does not allow duplicates.
-	 *
-	 * @param observer Observer to add.
-	 */
-	public void addObserver( Observer observer )
-	{
-		if ( !observers.contains(observer) ) { observers.add(observer); }
-	}
+  /**
+   * Constructs an Observable with zero Observers.
+   */
+  public Observable ()
+  {
+    changed = false;
+    observers = new Vector ();
+  }
 	
-	/**
-	 * Reset this Observable's state to unchanged.
-	 */
-	protected void clearChanged() { changed = false; }
+  /**
+   * Adds an Observer.
+   *
+   * @param observer Observer to add.
+   */
+  public void addObserver (Observer observer)
+  {
+    observers.add (observer);
+  }
+  
+  /**
+   * Reset this Observable's state to unchanged.
+   */
+  protected void clearChanged () 
+  { 
+    changed = false; 
+  }
+  
+  /**
+   * @return Number of Observers for this Observable.
+   */
+  public int countObservers() 
+  { 
+    return observers.size (); 
+  }
+  
+  /**
+   * Deletes an Observer of this Observable.
+   *
+   * @param victim Observer to delete.
+   */
+  public void deleteObserver (Observer victim) 
+  { 
+    observers.remove (victim); 
+  }
+  
+  /**
+   * Deletes all Observers of this Observable.
+   */
+  public void deleteObservers ()
+  {
+    observers.removeAllElements ();
+  }
+  
+  /**
+   * @return Whether or not this Observable has changed.
+   */
+  public boolean hasChanged () 
+  { 
+    return changed; 
+  }
+  
+  /**
+   * Tell Observers that this Observable has changed, then
+   * resets state to unchanged.
+   */
+  public void notifyObservers () 
+  { 
+    notifyObservers (null); 
+  }
+  
+  /**
+   * @param obj Arguement to Observer's update method.
+   */
+  public void notifyObservers (Object obj)
+  {
+    if (!changed) return;
+    Vector ob1 = (Vector) observers.clone ();
+    
+    for (int i = 0; i < ob1.size (); i++)
+      ((Observer)ob1.elementAt (i)).update (this, obj);
+    
+    changed = false;
+  }
 	
-	/**
-	 * @return Number of Observers for this Observable.
-	 */
-	public int countObservers() { return observers.size(); }
-	
-	/**
-	 * Deletes an Observer of this Observable.
-	 *
-	 * @param victim Observer to delete.
-	 */
-	public void deleteObserver( Observer victim ) { observers.remove(victim); }
-	
-	/**
-	 * Deletes all Observers of this Observable.
-	 */
-	public void deleteObservers()
-	{
-		Enumeration enum = observers.elements();
-		
-		while ( enum.hasMoreElements() )
-		{
-			deleteObserver( (Observer)enum.nextElement() );
-		}
-	}
+  /**
+   * Marks this Observable as having changed.
+   */
+  protected void setChanged () 
+  { 
+    changed = true; 
+  }
+}
 
-	/**
-	 * @return Whether or not this Observable has changed.
-	 */
-	public boolean hasChanged() { return changed; }
-	
-	/**
-	 * Tell Observers that this Observable has changed, then
-	 * resets state to unchanged.
-	 */
-	public void notifyObservers() { notifyObservers(null); }
-	
-	/**
-	 * @param obj Arguement to Observer's update method.
-	 */
-	public void notifyObservers( Object obj )
-	{
-		if ( hasChanged() )
-		{
-			Enumeration enum = observers.elements();
-			
-			while ( enum.hasMoreElements() )
-			{
-				( (Observer)enum.nextElement() ).update(this, obj);;
-			}
-			
-			clearChanged();
-		}
-	}
-	
-	/**
-	 * Marks this Observable as having changed.
-	 */
-	protected void setChanged() { changed = true; }
-}
\ No newline at end of file