content: /*
   * Copyright 2017-2025 Hyland Software, Inc. and its affiliates.
   *
   * 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 org.activiti.cloud.services.messages.core.support;
  
  import java.util.Comparator;
  import org.springframework.lang.Nullable;
  import org.springframework.messaging.Message;
  import org.springframework.messaging.MessageHeaders;
  
  public class MessageTimestampComparator implements Comparator<Message<?>> {
  
      @Override
      public int compare(Message<?> o1, Message<?> o2) {
          Long sequenceNumber1 = getTimestamp(o1);
          Long sequenceNumber2 = getTimestamp(o2);
  
          return Long.compare(sequenceNumber1, sequenceNumber2);
      }
  
      @Nullable
      public Long getTimestamp(Message<?> m) {
          Object value = m.getHeaders().get(MessageHeaders.TIMESTAMP);
          if (value == null) {
              return null;
          }
          return (value instanceof Long ? (Long) value : Long.parseLong(value.toString()));
      }
  }
  