How to use

JavaScriptUrlReferenceHeaderItem

in

org.apache.wicket.markup.head

/**
 * Creates a {@link JavaScriptUrlReferenceHeaderItem} for the given url.
 *
 * @param url
 *            context-relative url of the the javascript resource
 * @param id
 *            id that will be used to filter duplicate reference (it's still filtered by URL
 *            too)
 * @param defer
 *            specifies that the execution of a script should be deferred (delayed) until after
 *            the page has been loaded.
 * @param charset
 *            a non null value specifies the charset attribute of the script tag
 * @return A newly created {@link JavaScriptUrlReferenceHeaderItem} for the given url.
 */
public static JavaScriptUrlReferenceHeaderItem forUrl(String url, String id, boolean defer,
  String charset, String condition)
{
  return new JavaScriptUrlReferenceHeaderItem(url, id, defer, charset, condition);
}

@Override
public void render(Response response)
{
  internalRenderJavaScriptReference(response,
    UrlUtils.rewriteToContextRelative(getUrl(), RequestCycle.get()), getId(), isDefer(),
    getCharset(), getCondition(), isAsync());
}

@Override
public Iterable<?> getRenderTokens()
{
  String url = UrlUtils.rewriteToContextRelative(getUrl(), RequestCycle.get());
  if (Strings.isEmpty(getId()))
    return Collections.singletonList("javascript-" + url);
  else
    return Arrays.asList("javascript-" + getId(), "javascript-" + url);
}

@Override
public String toString()
{
  return "JavaScriptUrlReferenceHeaderItem(" + getUrl() + ")";
}

@Override
public void renderHead(final IHeaderResponse response) {
  super.renderHead(response);
  response.render(JavaScriptUrlReferenceHeaderItem.forReference(CKEditorConstants.getCKEditorJsReference()));
  response.render(OnDomReadyHeaderItem.forScript(getJavaScriptForCKEditorTimestamp()));
  response.render(JavaScriptUrlReferenceHeaderItem.forReference(CKEDITOR_PANEL_JS));
  final ObjectNode editorConfig = getConfigurationForEditor();
  renderContentsCss(response, editorConfig);
  response.render(OnDomReadyHeaderItem.forScript(getJavaScriptForEditor(editorConfig)));
}

@Override
public Iterable<?> getRenderTokens()
{
  String url = UrlUtils.rewriteToContextRelative(getUrl(), RequestCycle.get());
  if (Strings.isEmpty(getId()))
    return Collections.singletonList("javascript-" + url);
  else
    return Arrays.asList("javascript-" + getId(), "javascript-" + url);
}

@Override
public String toString()
{
  return "JavaScriptUrlReferenceHeaderItem(" + getUrl() + ")";
}

@Override
public void render(Response response)
{
  internalRenderJavaScriptReference(response,
    UrlUtils.rewriteToContextRelative(getUrl(), RequestCycle.get()), getId(), isDefer(),
    getCharset(), getCondition(), isAsync());
}

/**
 * Creates a {@link JavaScriptUrlReferenceHeaderItem} for the given url.
 *
 * @param url
 *            context-relative url of the the javascript resource
 * @param id
 *            id that will be used to filter duplicate reference (it's still filtered by URL
 *            too)
 * @param defer
 *            specifies that the execution of a script should be deferred (delayed) until after
 *            the page has been loaded.
 * @param charset
 *            a non null value specifies the charset attribute of the script tag
 * @return A newly created {@link JavaScriptUrlReferenceHeaderItem} for the given url.
 */
public static JavaScriptUrlReferenceHeaderItem forUrl(String url, String id, boolean defer,
  String charset, String condition)
{
  return new JavaScriptUrlReferenceHeaderItem(url, id, defer, charset, condition);
}

        null));
header.render(
    new JavaScriptUrlReferenceHeaderItem(
        ResponseUtils.buildURL(base, "/openlayers3/ol.js", null, URLType.RESOURCE),
        null,

  @Override
  public void renderHead(Component component, IHeaderResponse response) {
    HttpServletRequest req =
        getGeoServerApplication().servletRequest(getRequest());
    String baseUrl = baseURL(req);
    response.render(
        new CssUrlReferenceHeaderItem(
            buildURL(
                baseUrl,
                "openlayers3/ol.css",
                null,
                URLMangler.URLType.RESOURCE),
            null,
            null));
    response.render(
        new JavaScriptUrlReferenceHeaderItem(
            buildURL(
                baseUrl,
                "openlayers3/ol.js",
                null,
                URLMangler.URLType.RESOURCE),
            null,
            false,
            "UTF-8",
            null));
  }
});