/**
     * Enables or disables the action.
     *
     * @param newValue  true to enable the action, false to
     *                  disable it
     * @see Action#setEnabled
     */
    public void setEnabled(boolean newValue) {
	boolean oldValue = this.enabled;

	if (oldValue != newValue) {
	    this.enabled = newValue;
	    firePropertyChange("enabled", 
			       Boolean.valueOf(oldValue), Boolean.valueOf(newValue));
	}
    }


    /**
     * Returns an array of <code>Object</code>s which are keys for
     * which values have been set for this <code>AbstractAction</code>,
     * or <code>null</code> if no keys have values set.
     * @return an array of key objects, or <code>null</code> if no
     *			keys have values set
     * @since 1.3
     */
    public Object[] getKeys() {
	if (arrayTable == null) {
	    return null;
	}
	Object[] keys = new Object[arrayTable.size()];
	arrayTable.getKeys(keys);
	return keys;
    }

    /**
     * If any <code>PropertyChangeListeners</code> have been registered, the
     * <code>changeSupport</code> field describes them.
     */
    protected SwingPropertyChangeSupport changeSupport;

    /**
     * Supports reporting bound property changes.  This method can be called
     * when a bound property has changed and it will send the appropriate
     * <code>PropertyChangeEvent</code> to any registered 
     * <code>PropertyChangeListeners</code>.
     */
    protected void firePropertyChange(String propertyName, Object oldValue, Object newValue) {
        if (changeSupport == null || 
	    (oldValue != null && newValue != null && oldValue.equals(newValue))) {
            return;
        }
        changeSupport.firePropertyChange(propertyName, oldValue, newValue);
    }


    /**
     * Adds a <code>PropertyChangeListener</code> to the listener list.
     * The listener is registered for all properties.
     * <p>
     * A <code>PropertyChangeEvent</code> will get fired in response to setting
     * a bound property, e.g. <code>setFont</code>, <code>setBackground</code>,
     * or <code>setForeground</code>.
     * Note that if the current component is inheriting its foreground, 
     * background, or font from its container, then no event will be 
     * fired in response to a change in the inherited property.
     *
     * @param listener  The <code>PropertyChangeListener</code> to be added
     *
     * @see Action#addPropertyChangeListener 
     */
    public synchronized void addPropertyChangeListener(PropertyChangeListener listener) {
        if (changeSupport == null) {
	    changeSupport = new SwingPropertyChangeSupport(this);
        }
        changeSupport.addPropertyChangeListener(listener);
    }


    /**
     * Removes a <code>PropertyChangeListener</code> from the listener list.
     * This removes a <code>PropertyChangeListener</code> that was registered
     * for all properties.
     *
     * @param listener  the <code>PropertyChangeListener</code> to be removed
     *
     * @see Action#removePropertyChangeListener 
     */
    public synchronized void removePropertyChangeListener(PropertyChangeListener listener) {
        if (changeSupport == null) {
            return;
        }
        changeSupport.removePropertyChangeListener(listener);
    }


    /**
     * Returns an array of all the <code>PropertyChangeListener</code>s added
     * to this AbstractAction with addPropertyChangeListener().