| /* |
| 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. |
| # Copyright IBM Corp. 2015, 2016 |
| */ |
| package quarks.samples.apps; |
| |
| import java.util.Properties; |
| |
| import quarks.providers.direct.DirectProvider; |
| |
| /** |
| * A configuration driven factory for a Quarks topology provider. |
| */ |
| public class TopologyProviderFactory { |
| private final Properties props; |
| |
| /** |
| * Construct a factory |
| * @param props configuration information. |
| */ |
| public TopologyProviderFactory(Properties props) { |
| this.props = props; |
| } |
| |
| /** |
| * Get a new topology provider. |
| * <p> |
| * The default provider is {@code quarks.providers.direct.DirectProvider}. |
| * <p> |
| * The {@code topology.provider} configuration property can specify |
| * an alternative. |
| * |
| * @return the provider |
| * @throws Exception if the provider couldn't be created |
| */ |
| public DirectProvider newProvider() throws Exception { |
| String name = props.getProperty("topology.provider", "quarks.providers.direct.DirectProvider"); |
| Class<?> clazz = null; |
| try { |
| clazz = Class.forName(name); |
| } |
| catch (ClassNotFoundException e) { |
| String msg = "Class not found: "+e.getLocalizedMessage(); |
| System.err.println(msg); |
| throw new IllegalStateException(msg); |
| } |
| return (DirectProvider) clazz.newInstance(); |
| } |
| } |