| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package javax.websocket; |
| |
| import java.lang.reflect.InvocationTargetException; |
| import java.util.Iterator; |
| import java.util.ServiceLoader; |
| |
| /** |
| * Use the {@link ServiceLoader} mechanism to provide instances of the WebSocket |
| * client container. |
| */ |
| public abstract class ContainerProvider { |
| |
| private static final String DEFAULT_PROVIDER_CLASS_NAME = |
| "org.apache.tomcat.websocket.WsWebSocketContainer"; |
| |
| /** |
| * Create a new container used to create outgoing WebSocket connections. |
| * |
| * @return A newly created container. |
| */ |
| public static WebSocketContainer getWebSocketContainer() { |
| WebSocketContainer result = null; |
| |
| ServiceLoader<ContainerProvider> serviceLoader = |
| ServiceLoader.load(ContainerProvider.class); |
| Iterator<ContainerProvider> iter = serviceLoader.iterator(); |
| while (result == null && iter.hasNext()) { |
| result = iter.next().getContainer(); |
| } |
| |
| // Fall-back. Also used by unit tests |
| if (result == null) { |
| try { |
| @SuppressWarnings("unchecked") |
| Class<WebSocketContainer> clazz = |
| (Class<WebSocketContainer>) Class.forName( |
| DEFAULT_PROVIDER_CLASS_NAME); |
| result = clazz.getDeclaredConstructor().newInstance(); |
| } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | |
| IllegalArgumentException | InvocationTargetException | NoSuchMethodException | |
| SecurityException e) { |
| // No options left. Just return null. |
| } |
| } |
| return result; |
| } |
| |
| protected abstract WebSocketContainer getContainer(); |
| } |