HDFS-7778. Rename FsVolumeListTest to TestFsVolumeList and commit it to branch-2. Contributed by Lei (Eddy) Xu.

(cherry picked from commit 2efb2347a969ecff75934cd10f2432eade1d77dc)

Conflicts:
	hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/impl/TestFsVolumeList.java

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -651,6 +651,9 @@ Release 2.7.0 - UNRELEASED
     HDFS-7686. Re-add rapid rescan of possibly corrupt block feature to the
     block scanner (cmccabe)
 
+    HDFS-7778. Rename FsVolumeListTest to TestFsVolumeList and commit it to
+    branch-2. (Lei (Eddy) Xu via cnauroth)
+
     BREAKDOWN OF HDFS-7584 SUBTASKS AND RELATED JIRAS
 
       HDFS-7720. Quota by Storage Type API, tools and ClientNameNode

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/impl/TestFsVolumeList.java

@@ -0,0 +1,101 @@
+/**
+ * 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.fsdataset.impl;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.FileSystemTestHelper;
+import org.apache.hadoop.hdfs.DFSConfigKeys;
+import org.apache.hadoop.hdfs.StorageType;
+import org.apache.hadoop.hdfs.server.datanode.BlockScanner;
+import org.apache.hadoop.hdfs.server.datanode.fsdataset.FsVolumeReference;
+import org.apache.hadoop.hdfs.server.datanode.fsdataset.RoundRobinVolumeChoosingPolicy;
+import org.apache.hadoop.hdfs.server.datanode.fsdataset.VolumeChoosingPolicy;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+
+import static org.junit.Assert.assertNotEquals;
+import static org.mockito.Mockito.mock;
+
+public class TestFsVolumeList {
+
+  private final Configuration conf = new Configuration();
+  private VolumeChoosingPolicy<FsVolumeImpl> blockChooser =
+      new RoundRobinVolumeChoosingPolicy<>();
+  private FsDatasetImpl dataset = null;
+  private String baseDir;
+  private BlockScanner blockScanner;
+
+  @Before
+  public void setUp() {
+    dataset = mock(FsDatasetImpl.class);
+    baseDir = new FileSystemTestHelper().getTestRootDir();
+    Configuration blockScannerConf = new Configuration();
+    blockScannerConf.setInt(DFSConfigKeys.
+        DFS_DATANODE_SCAN_PERIOD_HOURS_KEY, -1);
+    blockScanner = new BlockScanner(null, blockScannerConf);
+  }
+
+  @Test
+  public void testGetNextVolumeWithClosedVolume() throws IOException {
+    FsVolumeList volumeList = new FsVolumeList(0, blockScanner, blockChooser);
+    List<FsVolumeImpl> volumes = new ArrayList<>();
+    for (int i = 0; i < 3; i++) {
+      File curDir = new File(baseDir, "nextvolume-" + i);
+      curDir.mkdirs();
+      FsVolumeImpl volume = new FsVolumeImpl(dataset, "storage-id", curDir,
+          conf, StorageType.DEFAULT);
+      volume.setCapacityForTesting(1024 * 1024 * 1024);
+      volumes.add(volume);
+      volumeList.addVolume(volume.obtainReference());
+    }
+
+    // Close the second volume.
+    volumes.get(1).closeAndWait();
+    for (int i = 0; i < 10; i++) {
+      try (FsVolumeReference ref =
+          volumeList.getNextVolume(StorageType.DEFAULT, 128)) {
+        // volume No.2 will not be chosen.
+        assertNotEquals(ref.getVolume(), volumes.get(1));
+      }
+    }
+  }
+
+  @Test
+  public void testCheckDirsWithClosedVolume() throws IOException {
+    FsVolumeList volumeList = new FsVolumeList(0, blockScanner, blockChooser);
+    List<FsVolumeImpl> volumes = new ArrayList<>();
+    for (int i = 0; i < 3; i++) {
+      File curDir = new File(baseDir, "volume-" + i);
+      curDir.mkdirs();
+      FsVolumeImpl volume = new FsVolumeImpl(dataset, "storage-id", curDir,
+          conf, StorageType.DEFAULT);
+      volumes.add(volume);
+      volumeList.addVolume(volume.obtainReference());
+    }
+
+    // Close the 2nd volume.
+    volumes.get(1).closeAndWait();
+    // checkDirs() should ignore the 2nd volume since it is closed.
+    volumeList.checkDirs();
+  }
+}