HDDS-1680. Create missing parent directories during the creation of HddsVolume dirs (#961)

Author: elek

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/common/volume/HddsVolume.java

@@ -204,7 +204,7 @@ private void initialize() throws IOException {
     switch (intialVolumeState) {
     case NON_EXISTENT:
       // Root directory does not exist. Create it.
-      if (!hddsRootDir.mkdir()) {
+      if (!hddsRootDir.mkdirs()) {
         throw new IOException("Cannot create directory " + hddsRootDir);
       }
       setState(VolumeState.NOT_FORMATTED);

hadoop-hdds/container-service/src/test/java/org/apache/hadoop/ozone/container/common/volume/TestVolumeSet.java

@@ -230,7 +230,7 @@ public void testFailVolumes() throws  Exception{
     ozoneConfig.set(HDDS_DATANODE_DIR_KEY, readOnlyVolumePath.getAbsolutePath()
         + "," + volumePath.getAbsolutePath());
     volSet = new VolumeSet(UUID.randomUUID().toString(), ozoneConfig);
-    assertTrue(volSet.getFailedVolumesList().size() == 1);
+    assertEquals(1, volSet.getFailedVolumesList().size());
     assertEquals(readOnlyVolumePath, volSet.getFailedVolumesList().get(0)
         .getHddsRootDir());