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.underfs;
  
  import alluxio.file.options.DescendantType;
  
  import java.util.concurrent.CountDownLatch;
  import java.util.concurrent.atomic.AtomicReference;
  
  /**
   * Test utils for UFS.
   */
  public class UnderFileSystemTestUtil {
    /**
     * A test helper convert the async performListingAsync call to a sync one.
     * @param ufs the ufs object
     * @param path the path
     * @param descendantType the descendant type
     * @return the ufs load result
     */
    public static UfsLoadResult performListingAsyncAndGetResult(
        UnderFileSystem ufs, String path, DescendantType descendantType) throws Throwable {
      CountDownLatch latch = new CountDownLatch(1);
      AtomicReference<Throwable> throwable = new AtomicReference<>();
      AtomicReference<UfsLoadResult> result = new AtomicReference<>();
      ufs.performListingAsync(path, null, null, descendantType, descendantType == DescendantType.NONE,
          (r) -> {
            result.set(r);
            latch.countDown();
          }, (t) -> {
            throwable.set(t);
            latch.countDown();
          });
      latch.await();
      if (throwable.get() != null) {
        throw throwable.get();
      }
      return result.get();
    }
  }
  