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.artemis.utils.actors;
  
  import java.util.concurrent.Executor;
  
  import org.apache.activemq.artemis.api.core.ActiveMQInterruptedException;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import java.lang.invoke.MethodHandles;
  
  /**
   * An executor that always runs all tasks in order, using a delegate executor to run the tasks.
   * <p>
   * More specifically, any call B to the {@link #execute(Runnable)} method that happens-after another call A to the
   * same method, will result in B's task running after A's.
   */
  public class OrderedExecutor extends ProcessorBase<Runnable> implements ArtemisExecutor {
  
     public OrderedExecutor(Executor delegate) {
        super(delegate);
     }
  
     private static final Logger logger = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
  
     private boolean fair;
  
     @Override
     public boolean isFair() {
        return fair;
     }
  
     /**
      * If this OrderedExecutor is fair, it will yield for another executors after each task ran
      */
     @Override
     public OrderedExecutor setFair(boolean fair) {
        this.fair = fair;
        return this;
     }
  
     @Override
     protected final void doTask(Runnable task) {
        try {
           task.run();
           if (fair) {
              this.yield();
           }
        } catch (ActiveMQInterruptedException e) {
           // This could happen during shutdowns. Nothing to be concerned about here
           logger.debug("Interrupted Thread", e);
        } catch (Throwable t) {
           logger.warn(t.getMessage(), t);
        }
  
     }
  
     @Override
     public final void execute(Runnable run) {
        task(run);
     }
  
     @Override
     public String toString() {
        return "OrderedExecutor(tasks=" + tasks + ")";
     }
  
  }
  