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.Optional;
  import java.util.concurrent.atomic.AtomicReference;
  
  import com.google.common.util.concurrent.Atomics;
  
  import org.apache.aurora.scheduler.storage.SchedulerStore;
  
  /**
   * An in-memory scheduler store.
   */
  class MemSchedulerStore implements SchedulerStore.Mutable {
    private final AtomicReference<String> frameworkId = Atomics.newReference();
  
    @Override
    public void saveFrameworkId(String newFrameworkId) {
      frameworkId.set(newFrameworkId);
    }
  
    @Override
    public Optional<String> fetchFrameworkId() {
      return Optional.ofNullable(frameworkId.get());
    }
  }
  