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diff --git a/libjava/classpath/javax/swing/event/EventListenerList.java b/libjava/classpath/javax/swing/event/EventListenerList.java
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+/* EventListenerList.java --
+   Copyright (C) 2002, 2004, 2005, 2006,  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., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+package javax.swing.event;
+
+import gnu.java.lang.CPStringBuilder;
+
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.io.Serializable;
+import java.lang.reflect.Array;
+import java.util.EventListener;
+
+
+/**
+ * A utility class for keeping track of {@link EventListener}s.
+ *
+ * <p><b>Example for using this class:</b>
+ *
+ * <blockquote><pre> import java.util.EventListener;
+ * import javax.swing.event.EventListenerList;
+ *
+ * class Foo
+ * {
+ *   protected final EventListenerList listeners = new EventListenerList();
+ *   protected BarClosedEvent barClosedEvent = null;
+ *
+ *   public void addBarListener(BarListener l)
+ *   {
+ *     listeners.<a href="#add(java.lang.Class, java.util.EventListener)"
+ *               >add</a>(BarListener.class, l);
+ *   }
+ *
+ *   public void removeBarListener(BarListener l)
+ *   {
+ *     listeners.<a href="#remove(java.lang.Class, java.util.EventListener)"
+ *               >remove</a>(BarListener.class, l);
+ *   }
+ *
+ *   protected void fireBarClosedEvent()
+ *   {
+ *     Object[] l = listeners.<a href="#getListenerList()"
+ *                            >getListenerList()</a>;
+ *
+ *     for (int i = l.length - 2; i >= 0; i -= 2)
+ *       if (l[i] == BarListener.class)
+ *         {
+ *           // Create the event on demand, when it is needed the first time.
+ *           if (barClosedEvent == null)
+ *             barClosedEvent = new BarClosedEvent(this);
+ *
+ *           ((BarClosedListener) l[i + 1]).barClosed(barClosedEvent);
+ *         }
+ *   }
+ * }</pre></blockquote>
+ *
+ * @author Andrew Selkirk (aselkirk@sympatico.ca)
+ * @author Sascha Brawer (brawer@dandelis.ch)
+ */
+public class EventListenerList
+  implements Serializable
+{
+  /**
+   * An ID for serializing instances of this class; verified with the
+   * serialver tool of Sun J2SE 1.4.1_01.
+   */
+  static final long serialVersionUID = -5677132037850737084L;
+
+
+  /**
+   * An empty array that is shared by all instances of this class that
+   * have no listeners.
+   */
+  private static final Object[] NO_LISTENERS = new Object[0];
+
+
+  /**
+   * An array with all currently registered listeners.  The array has
+   * twice as many elements as there are listeners.  For an even
+   * integer <code>i</code>, <code>listenerList[i]</code> indicates
+   * the registered class, and <code>listenerList[i + 1]</code> is the
+   * listener.
+   */
+  protected transient Object[] listenerList = NO_LISTENERS;
+
+
+  /**
+   * EventListenerList constructor
+   */
+  public EventListenerList()
+  {
+    // Nothing to do here.
+  }
+
+
+  /**
+   * Registers a listener of a specific type.
+   *
+   * @param t the type of the listener.
+   *
+   * @param listener the listener to add, which must be an instance of
+   * <code>t</code>, or of a subclass of <code>t</code>.
+   *
+   * @throws IllegalArgumentException if <code>listener</code> is not
+   * an instance of <code>t</code> (or a subclass thereof).
+   *
+   * @throws NullPointerException if <code>t</code> is <code>null</code>.
+   */
+  public <T extends EventListener> void add(Class<T> t, T listener)
+  {
+    int oldLength;
+    Object[] newList;
+
+    if (listener == null)
+      return;
+
+    if (!t.isInstance(listener))
+      throw new IllegalArgumentException();
+
+    oldLength = listenerList.length;
+    newList = new Object[oldLength + 2];
+    if (oldLength > 0)
+      System.arraycopy(listenerList, 0, newList, 0, oldLength);
+
+    newList[oldLength] = t;
+    newList[oldLength + 1] = listener;
+    listenerList = newList;
+  }
+
+
+  /**
+   * Determines the number of listeners.
+   */
+  public int getListenerCount()
+  {
+    return listenerList.length / 2;
+  }
+
+
+  /**
+   * Determines the number of listeners of a particular class.
+   *
+   * @param t the type of listeners to be counted. In order to get
+   * counted, a subscribed listener must be exactly of class
+   * <code>t</code>. Thus, subclasses of <code>t</code> will not be
+   * counted.
+   */
+  public int getListenerCount(Class<?> t)
+  {
+    int result = 0;
+    for (int i = 0; i < listenerList.length; i += 2)
+      if (t == listenerList[i])
+        ++result;
+
+    return result;
+  }
+
+
+  /**
+   * Returns an array containing a sequence of listenerType/listener pairs, one
+   * for each listener.
+   *
+   * @return An array containing the listener types and references.
+   */
+  public Object[] getListenerList()
+  {
+    // returning the internal storage is a bad idea, but tests show that the
+    // reference implementation does this...
+    return listenerList;
+  }
+
+
+  /**
+   * Retrieves the currently subscribed listeners of a particular
+   * type.  For a listener to be returned, it must have been
+   * registered with exactly the type <code>c</code>; subclasses are
+   * not considered equal.
+   *
+   * <p>The returned array can always be cast to <code>c[]</code>.
+   * Since it is a newly allocated copy, the caller may arbitrarily
+   * modify the array.
+   *
+   * @param c the class which was passed to {@link #add}.
+   *
+   * @throws ClassCastException if <code>c</code> does not implement
+   * the {@link EventListener} interface.
+   *
+   * @throws NullPointerException if <code>c</code> is
+   * <code>null</code>.
+   *
+   * @return an array of <code>c</code> whose elements are the
+   * currently subscribed listeners of the specified type.  If there
+   * are no such listeners, an empty array is returned.
+   *
+   * @since 1.3
+   */
+  public <T extends EventListener> T[] getListeners(Class<T> c)
+  {
+    int count, f;
+    EventListener[] result;
+
+    count = getListenerCount(c);
+    result = (EventListener[]) Array.newInstance(c, count);
+    f = 0;
+    for (int i = listenerList.length - 2; i >= 0; i -= 2)
+      if (listenerList[i] == c)
+        result[f++] = (EventListener) listenerList[i + 1];
+
+    return (T[]) result;
+  }
+
+
+  /**
+   * Removes a listener of a specific type.
+   *
+   * @param t the type of the listener.
+   *
+   * @param listener the listener to remove, which must be an instance
+   * of <code>t</code>, or of a subclass of <code>t</code>.
+   *
+   * @throws IllegalArgumentException if <code>listener</code> is not
+   * an instance of <code>t</code> (or a subclass thereof).
+   *
+   * @throws NullPointerException if <code>t</code> is <code>null</code>.
+   */
+  public <T extends EventListener> void remove(Class<T> t, T listener)
+  {
+    Object[] oldList, newList;
+    int oldLength;
+
+    if (listener == null)
+      return;
+
+    if (!t.isInstance(listener))
+      throw new IllegalArgumentException();
+
+    oldList = listenerList;
+    oldLength = oldList.length;
+    for (int i = 0; i < oldLength; i += 2)
+      if (oldList[i] == t && oldList[i + 1] == listener)
+        {
+          if (oldLength == 2)
+            newList = NO_LISTENERS;
+          else
+            {
+              newList = new Object[oldLength - 2];
+              if (i > 0)
+                System.arraycopy(oldList, 0, newList, 0, i);
+              if (i < oldLength - 2)
+                System.arraycopy(oldList, i + 2, newList, i,
+                                 oldLength - 2 - i);
+            }
+          listenerList = newList;
+          return;
+        }
+  }
+
+
+  /**
+   * Returns a string representation of this object that may be useful
+   * for debugging purposes.
+   */
+  public String toString()
+  {
+    CPStringBuilder buf = new CPStringBuilder("EventListenerList: ");
+    buf.append(listenerList.length / 2);
+    buf.append(" listeners: ");
+    for (int i = 0; i < listenerList.length; i += 2)
+      {
+        buf.append(" type ");
+        buf.append(((Class) listenerList[i]).getName());
+        buf.append(" listener ");
+        buf.append(listenerList[i + 1]);
+      }
+    return buf.toString();
+  }
+
+  /**
+   * Serializes an instance to an ObjectOutputStream.
+   *
+   * @param out the stream to serialize to
+   *
+   * @throws IOException if something goes wrong
+   */
+  private void writeObject(ObjectOutputStream out)
+    throws IOException
+  {
+    out.defaultWriteObject();
+    for (int i = 0; i < listenerList.length; i += 2)
+      {
+        Class cl = (Class) listenerList[i];
+        EventListener l = (EventListener) listenerList[i + 1];
+        if (l != null && l instanceof Serializable)
+          {
+            out.writeObject(cl.getName());
+            out.writeObject(l);
+          }
+      }
+    // Write end marker.
+    out.writeObject(null);
+  }
+
+  /**
+   * Deserializes an instance from an ObjectInputStream.
+   *
+   * @param in the input stream
+   *
+   * @throws ClassNotFoundException if a serialized class can't be found
+   * @throws IOException if something goes wrong
+   */
+  private <T extends EventListener> void readObject(ObjectInputStream in)
+    throws ClassNotFoundException, IOException
+  {
+    listenerList = NO_LISTENERS;
+    in.defaultReadObject();
+    Object type;
+    ClassLoader cl = Thread.currentThread().getContextClassLoader();
+    while ((type = in.readObject()) != null)
+      {
+        EventListener l = (EventListener) in.readObject();
+        add(((Class<T>) Class.forName((String) type, true, cl)), (T) l);
+      }
+  }
+}