1 files changed, 90 insertions, 33 deletions

diff --git a/libjava/java/util/Observable.java b/libjava/java/util/Observable.java
index 1a205c1..5d4d49f 100644
--- a/libjava/java/util/Observable.java
+++ b/libjava/java/util/Observable.java
@@ -1,30 +1,49 @@
-/* Copyright (C) 1998, 1999  Free Software Foundation
+/* java.util.Observable
+   Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.
 
-   This file is part of libgcj.
+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 software is copyrighted work licensed under the terms of the
-Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
-details.  */
 
 package java.util;
- 
-/**
- * @author Warren Levy <warrenl@cygnus.com>
- * @date September 2, 1998.
- */
+
 /* Written using "Java Class Libraries", 2nd edition, ISBN 0-201-31002-3
  * "The Java Language Specification", ISBN 0-201-63451-1
  * plus online API docs for JDK 1.2 beta from http://www.javasoft.com.
  * Status:  Believed complete and correct.
  */
- 
+
+/**
+ * @author Warren Levy <warrenl@cygnus.com>
+ * @date September 2, 1998.
+ */
 public class Observable
 {
-  /* tracks whether this object has changed */
+  /** tracks whether this object has changed */
   private boolean changed;
 
   /* list of the Observers registered as interested in this Observable */
-  private Vector observerVec;
+  private Vector observers;
 
   /* TBD: This might be better implemented as an Observer[]
    * but that would mean writing more code rather than making use of
@@ -34,63 +53,101 @@ public class Observable
    * we may decide to make the tradeoff and reimplement with an Observer[].
    */
 
+  /**
+   * Constructs an Observable with zero Observers.
+   */
   public Observable()
   {
     changed = false;
-    observerVec = new Vector();
+    observers = new Vector();
   }
 
-  public synchronized void addObserver(Observer obs)
+  /**
+   * Adds an Observer. If the observer was already added this method does
+   * nothing.
+   *
+   * @param observer Observer to add.
+   */
+  public synchronized void addObserver(Observer observer)
   {
-    // JDK 1.2 spec says not to add this if it is already there
-    if (!observerVec.contains(obs))
-      observerVec.addElement(obs);
+    if (!observers.contains(observer))
+      observers.addElement(observer);
   }
 
+  /**
+   * Reset this Observable's state to unchanged.
+   */
   protected synchronized void clearChanged()
   {
     changed = false;
   }
 
+  /**
+   * @return Number of Observers for this Observable.
+   */
   public synchronized int countObservers()
   {
-    return observerVec.size();
+    return observers.size();
   }
 
-  public synchronized void deleteObserver(Observer obs)
+  /**
+   * Deletes an Observer of this Observable.
+   *
+   * @param victim Observer to delete.
+   */
+  public synchronized void deleteObserver(Observer victim)
   {
-    observerVec.removeElement(obs);
+    observers.removeElement(victim);
   }
 
+  /**
+   * Deletes all Observers of this Observable.
+   */
   public synchronized void deleteObservers()
   {
-    observerVec.removeAllElements();
+    observers.removeAllElements();
   }
 
+  /**
+   * @return Whether or not this Observable has changed.
+   */
   public synchronized boolean hasChanged()
   {
     return changed;
   }
 
+  /**
+   * If the Observable has actually changed then tell all Observers about it,
+   * then resets state to unchanged.
+   */
   public void notifyObservers()
   {
     notifyObservers(null);
   }
 
-  public void notifyObservers(Object arg)
+  /**
+   * If the Observable has actually changed then tell all Observers about it,
+   * then resets state to unchanged. 
+   * Note that though the order of notification is unspecified in subclasses,
+   * in Observable it is in the order of registration.
+   *
+   * @param obj Arguement to Observer's update method.
+   */
+  public void notifyObservers(Object obj)
   {
-    if (changed)
-      {
-	/* The JDK 1.2 spec states that though the order of notification
-	 * is unspecified in subclasses, in Observable it is in the order
-	 * of registration.
-	 */
-        for (int i = 0, numObs = observerVec.size(); i < numObs; i++)
-          ((Observer) (observerVec.elementAt(i))).update(this, arg);
-        changed = false;
-      }
+    if (!hasChanged())
+      return;
+    Vector ob1 = (Vector) observers.clone();
+
+    for (int i = 0; i < ob1.size(); i++)
+      ((Observer) ob1.elementAt(i)).update(this, obj);
+
+    clearChanged();
   }
 
+  /**
+   * Marks this Observable as having changed.
+   */
   protected synchronized void setChanged()
   {
     changed = true;