/**
 * 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 org.apache.hadoop.hdfs.server.datanode;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hdfs.DFSConfigKeys;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.apache.hadoop.hdfs.protocol.datatransfer.PipelineAck;
import org.junit.Assert;
import org.junit.Test;

import java.io.IOException;

public class TestDataNodeECN {
  @Test
  public void testECNFlag() throws IOException {
    Configuration conf = new Configuration();
    conf.setBoolean(DFSConfigKeys.DFS_PIPELINE_ECN_ENABLED, true);
    MiniDFSCluster cluster = null;
    try {
      cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1).build();
      PipelineAck.ECN ecn = cluster.getDataNodes().get(0).getECN();
      Assert.assertNotEquals(PipelineAck.ECN.DISABLED, ecn);
    } finally {
      if (cluster != null) {
        cluster.shutdown();
      }
    }
  }
}

Add the missing files for HDFS-8009.