001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.wicket.protocol.ws.api; 018 019import java.util.List; 020 021import org.apache.wicket.Application; 022import org.apache.wicket.ajax.WicketAjaxJQueryResourceReference; 023import org.apache.wicket.markup.head.HeaderItem; 024import org.apache.wicket.markup.head.JavaScriptHeaderItem; 025import org.apache.wicket.request.resource.JavaScriptResourceReference; 026import org.apache.wicket.request.resource.ResourceReference; 027 028/** 029 * A resource reference that provides the JavaScript that may be used to create WebSocket 030 * connections in the browser. The benefit over usage of plain <code>window.WebSocket<code> 031 * is that it supports handling of Wicket's <ajax-response> responses. 032 * 033 * @since 6.0 034 */ 035public class WicketWebSocketJQueryResourceReference extends JavaScriptResourceReference 036{ 037 private static final long serialVersionUID = 1; 038 039 private static final WicketWebSocketJQueryResourceReference instance = new WicketWebSocketJQueryResourceReference(); 040 041 /** 042 * @return the singleton instance 043 */ 044 public static WicketWebSocketJQueryResourceReference get() 045 { 046 return instance; 047 } 048 049 private WicketWebSocketJQueryResourceReference() 050 { 051 super(WicketWebSocketJQueryResourceReference.class, "res/js/wicket-websocket-jquery.js"); 052 } 053 054 @Override 055 public List<HeaderItem> getDependencies() 056 { 057 final ResourceReference wicketAjaxReference; 058 if (Application.exists()) 059 { 060 wicketAjaxReference = Application.get().getJavaScriptLibrarySettings().getWicketAjaxReference(); 061 } 062 else 063 { 064 wicketAjaxReference = WicketAjaxJQueryResourceReference.get(); 065 } 066 List<HeaderItem> dependencies = super.getDependencies(); 067 dependencies.add(JavaScriptHeaderItem.forReference(wicketAjaxReference)); 068 return dependencies; 069 } 070}