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 com.cloud.agent.manager.allocator.impl;
  
  import java.util.ArrayList;
  import java.util.List;
  
  import com.cloud.deploy.DeploymentPlan;
  import com.cloud.deploy.DeploymentPlanner.ExcludeList;
  import com.cloud.host.Host;
  import com.cloud.host.Host.Type;
  import com.cloud.vm.VirtualMachineProfile;
  import org.apache.logging.log4j.ThreadContext;
  
  public class FirstFitRoutingAllocator extends FirstFitAllocator {
      @Override
      public List<Host> allocateTo(VirtualMachineProfile vmProfile, DeploymentPlan plan, Type type, ExcludeList avoid, int returnUpTo) {
          try {
              ThreadContext.push("FirstFitRoutingAllocator");
              if (type != Host.Type.Routing) {
                  // FirstFitRoutingAllocator is to find space on routing capable hosts only
                  return new ArrayList<Host>();
              }
              //all hosts should be of type routing anyway.
              return super.allocateTo(vmProfile, plan, type, avoid, returnUpTo);
          } finally {
              ThreadContext.pop();
          }
      }
  }
  