Java tutorial
/* * 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 org.apache.accumulo.server.replication; import static java.util.Objects.requireNonNull; import java.util.Map.Entry; import org.apache.accumulo.core.replication.ReplicationTarget; import org.apache.accumulo.server.zookeeper.DistributedWorkQueue; import com.google.common.collect.Maps; /** * */ public class DistributedWorkQueueWorkAssignerHelper { public static final String KEY_SEPARATOR = "|"; /** * Serialize a filename and a {@link ReplicationTarget} into the expected key format for use with the {@link DistributedWorkQueue} * * @param filename * Filename for data to be replicated * @param replTarget * Information about replication peer * @return Key for identifying work in queue */ public static String getQueueKey(String filename, ReplicationTarget replTarget) { return filename + KEY_SEPARATOR + replTarget.getPeerName() + KEY_SEPARATOR + replTarget.getRemoteIdentifier() + KEY_SEPARATOR + replTarget.getSourceTableId(); } /** * @param queueKey * Key from the work queue * @return Components which created the queue key */ public static Entry<String, ReplicationTarget> fromQueueKey(String queueKey) { requireNonNull(queueKey); int index = queueKey.indexOf(KEY_SEPARATOR); if (-1 == index) { throw new IllegalArgumentException("Could not find expected separator in queue key '" + queueKey + "'"); } String filename = queueKey.substring(0, index); int secondIndex = queueKey.indexOf(KEY_SEPARATOR, index + 1); if (-1 == secondIndex) { throw new IllegalArgumentException("Could not find expected separator in queue key '" + queueKey + "'"); } int thirdIndex = queueKey.indexOf(KEY_SEPARATOR, secondIndex + 1); if (-1 == thirdIndex) { throw new IllegalArgumentException("Could not find expected seperator in queue key '" + queueKey + "'"); } return Maps.immutableEntry(filename, new ReplicationTarget(queueKey.substring(index + 1, secondIndex), queueKey.substring(secondIndex + 1, thirdIndex), queueKey.substring(thirdIndex + 1))); } }