/* * Copyright 2012 Research Studios Austria Forschungsges.m.b.H. * * Licensed 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 won.bot.framework.component.nodeurisource.impl; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import won.bot.framework.component.nodeurisource.NodeURISource; import java.net.URI; import java.util.ArrayList; import java.util.Collection; import java.util.List; /** * NodeUriSource that is given a list of URIs and returns each element in a round robin fashion. */ public class RoundRobinMultiNodeUriSource implements NodeURISource { private final Logger logger = LoggerFactory.getLogger(getClass()); private List<URI> nodeURIs = null; private int lastIndex = -1; @Override public URI getNodeURI() { if (this.nodeURIs == null || this.nodeURIs.isEmpty()) return null; int index = lastIndex + 1; if (index >= this.nodeURIs.size()){ index = 0; } URI nodeUri = this.nodeURIs.get(index); this.lastIndex = index; logger.debug("using node URI '{}'", nodeUri); return nodeUri; } public void setNodeURIs(final Collection<URI> nodeURIs) { if (nodeURIs == null){ this.nodeURIs = new ArrayList<URI>(); } else { this.nodeURIs = new ArrayList<URI>(nodeURIs.size()); this.nodeURIs.addAll(nodeURIs); } } }