content: /*
   * 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.camel.component.zookeeper;
  
  import org.apache.zookeeper.CreateMode;
  
  /**
   * Nodes created with any of Sequential {@link CreateMode}s will have a 10 character sequence attached to their node
   * names. <code>SequenceComparator</code> is a Natural comparator used to compare lists of objects with these appended
   * sequences.
   */
  public class SequenceComparator extends NaturalSortComparator {
  
      public static final int ZOOKEEPER_SEQUENCE_LENGTH = 10;
  
      @Override
      public int compare(CharSequence sequencedNode, CharSequence otherSequencedNode) {
          if (sequencedNode == null && otherSequencedNode == null) {
              return 0;
          }
          if (sequencedNode != null && otherSequencedNode == null) {
              return 1;
          }
          if (sequencedNode == null && otherSequencedNode != null) {
              return -1;
          }
          return super.compare(getZooKeeperSequenceNumber(sequencedNode), getZooKeeperSequenceNumber(otherSequencedNode));
      }
  
      private CharSequence getZooKeeperSequenceNumber(CharSequence sequencedNodeName) {
          int len = sequencedNodeName.length();
          return sequencedNodeName.subSequence(len - ZOOKEEPER_SEQUENCE_LENGTH, len);
      }
  }
  