Favicon with Wicket and HeaderContributer

Based on Michael's example, I did a complete example for a Wicket header contributer generating a favicon entry:

public class FavIconHeaderContributor extends AbstractHeaderContributor {
 
 private static final long serialVersionUID = 1L;

 private final FavIconContributor contributor;
 
 private static final class FavIconContributor implements IHeaderContributor {
 
  private static final long serialVersionUID = 1L;
  
  ResourceReference _resourceReference;
 
  public FavIconContributor(ResourceReference resourceReference) {
   _resourceReference = resourceReference;
  }
 
  public void renderHead(IHeaderResponse response) {
   CharSequence url = RequestCycle.get().urlFor(_resourceReference);
   response.renderString(getFavIconReference(url));
  }
 
  private CharSequence getFavIconReference(CharSequence url) {
   StringBuilder sb = new StringBuilder();
   sb.append("<link rel=\"shortcut icon\" href=\"");
   sb.append(url);
   sb.append("\" type=\"image/x-icon\">\n");
   return sb.toString();
  }
  
 }
 
 public FavIconHeaderContributor(ResourceReference resourceReference) {
  contributor = new FavIconContributor(resourceReference);
 }

 @Override
 public final IHeaderContributor[] getHeaderContributors() {
  return new IHeaderContributor[] { contributor };
 }

 @Override
 public String toString() {
  return contributor._resourceReference.getName();
 }
 
}