/*
* 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 jakarta.websocket;
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.getConstructor().newInstance();
} catch (ReflectiveOperationException | IllegalArgumentException | SecurityException ignore) {
// No options left. Just return null.
}
}
return result;
}
protected abstract WebSocketContainer getContainer();
}