content: /*
   * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
   * (the "License"). You may not use this work except in compliance with the License, which is
   * available at www.apache.org/licenses/LICENSE-2.0
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
   * either express or implied, as more fully set forth in the License.
   *
   * See the NOTICE file distributed with this work for information regarding copyright ownership.
   */
  
  package alluxio.client.file.cache.evictor;
  
  import alluxio.client.file.cache.PageId;
  
  import java.util.function.Predicate;
  import javax.annotation.Nullable;
  import javax.annotation.concurrent.ThreadSafe;
  
  /**
   * A client-side cache eviction policy that evicts nothing for debugging purposes.
   */
  @ThreadSafe
  public class UnevictableCacheEvictor implements CacheEvictor {
    /**
     * Required constructor.
     *
     * @param options
     */
    public UnevictableCacheEvictor(CacheEvictorOptions options) {}
  
    @Override
    public void updateOnGet(PageId pageId) {}
  
    @Override
    public void updateOnPut(PageId pageId) {}
  
    @Override
    public void updateOnDelete(PageId pageId) {}
  
    @Override
    public PageId evict() {
      return null;
    }
  
    @Nullable
    @Override
    public PageId evictMatching(Predicate<PageId> criterion) {
      return null;
    }
  
    @Override
    public void reset() {}
  }
  