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.activemq.store;
  
  import org.apache.activemq.broker.ConnectionContext;
  import org.apache.activemq.command.Message;
  
  /**
   * callback when the index is updated, allows ordered work to be seen by destinations
   */
  public interface IndexListener {
  
      final class MessageContext {
          public final Message message;
          public final ConnectionContext context;
          public final Runnable onCompletion;
          public boolean duplicate;
  
          public MessageContext(ConnectionContext context, Message message, Runnable onCompletion) {
              this.context = context;
              this.message = message;
              this.onCompletion = onCompletion;
          }
      }
  
      /**
       *  called with some global index lock held so that a listener can do order
       *  dependent work
       *  non null MessageContext.onCompletion called when work is done
       */
      public void onAdd(MessageContext messageContext);
  
  }
  