Bug 28638 [Preferences] Import Preferences: Crashes on eclipse
bundles/org.eclipse.jface/src/org/eclipse/jface/resource/FontRegistry.java
* with it, and automatically disposes of them when the SWT Display
 * that creates the fonts is disposed. Because of this, clients do 
 * not need to (indeed, must not attempt to) dispose of font 
 * objects themselves.
 * </p>
 * <p>
 * A special constructor is provided for populating a font registry
 * from a property files using the standard Java resource bundle mechanism.
 * </p>
 * <p>
 * Methods are provided for registering listeners that will be kept
 * apprised of changes to list of registed fonts.
 * </p>
 * <p>
 * Clients may instantiate this class (it was not designed to be subclassed).
 * </p>
 */
public class FontRegistry {
	/**
	 * List of property change listeners
	 * (element type: <code>org.eclipse.jface.util.IPropertyChangeListener</code>).
	 */
	private ListenerList listeners = new ListenerList();
	/**
	 * Table of known fonts, keyed by symbolic font name
	 * (key type: <code>String</code>, 
	 *  value type: <code>org.eclipse.swt.graphics.Font</code>.
	 */
	private Map stringToFont = new HashMap(7);
	/**