content: /**
   * 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.apache.aurora.scheduler.storage.mem;
  
  import java.util.Map;
  import java.util.Optional;
  import java.util.Set;
  
  import javax.inject.Inject;
  
  import com.google.common.annotations.VisibleForTesting;
  import com.google.common.collect.ImmutableSet;
  import com.google.common.collect.Maps;
  
  import org.apache.aurora.common.stats.StatsProvider;
  import org.apache.aurora.scheduler.storage.HostMaintenanceStore;
  import org.apache.aurora.scheduler.storage.entities.IHostMaintenanceRequest;
  
  public class MemHostMaintenanceStore implements HostMaintenanceStore.Mutable {
    @VisibleForTesting
    static final String MAINTENANCE_STORE_SIZE = "mem_storage_maintenance_size";
  
    private final Map<String, IHostMaintenanceRequest> hostMaintenanceRequests =
        Maps.newConcurrentMap();
  
    @Inject
    MemHostMaintenanceStore(StatsProvider statsProvider) {
      statsProvider.makeGauge(MAINTENANCE_STORE_SIZE, hostMaintenanceRequests::size);
    }
  
    @Override
    public Optional<IHostMaintenanceRequest> getHostMaintenanceRequest(String host) {
      return Optional.ofNullable(hostMaintenanceRequests.get(host));
    }
  
    @Override
    public Set<IHostMaintenanceRequest> getHostMaintenanceRequests() {
      return ImmutableSet.copyOf(hostMaintenanceRequests.values());
    }
  
    @Override
    public void deleteHostMaintenanceRequests() {
      hostMaintenanceRequests.clear();
    }
  
    @Override
    public void saveHostMaintenanceRequest(IHostMaintenanceRequest hostMaintenanceRequest) {
      hostMaintenanceRequests.put(hostMaintenanceRequest.getHost(), hostMaintenanceRequest);
    }
  
    @Override
    public void removeHostMaintenanceRequest(String host) {
      hostMaintenanceRequests.remove(host);
    }
  }
  