HDFS-4651. Adding missed files in the previous commit.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1@1462876 13f79535-47bb-0310-9956-ffa450edef68

src/test/org/apache/hadoop/hdfs/protocol/TestLayoutVersion.java

@@ -0,0 +1,86 @@
+/**
+ * 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.protocol;
+
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+
+import java.util.EnumSet;
+
+import org.apache.hadoop.hdfs.protocol.LayoutVersion.Feature;
+import org.junit.Test;
+
+/**
+ * Test for {@link LayoutVersion}
+ */
+public class TestLayoutVersion {
+  
+  /**
+   * Tests to make sure a given layout version supports all the
+   * features from the ancestor
+   */
+  @Test
+  public void testFeaturesFromAncestorSupported() {
+    for (Feature f : Feature.values()) {
+      validateFeatureList(f);
+    }
+  }
+  
+  /**
+   * Test to make sure 0.20.203 supports delegation token
+   */
+  @Test
+  public void testRelease203() {
+    assertTrue(LayoutVersion.supports(Feature.DELEGATION_TOKEN, 
+        Feature.RESERVED_REL20_203.lv));
+  }
+  
+  /**
+   * Test to make sure 0.20.204 supports delegation token
+   */
+  @Test
+  public void testRelease204() {
+    assertTrue(LayoutVersion.supports(Feature.DELEGATION_TOKEN, 
+        Feature.RESERVED_REL20_204.lv));
+  }
+  
+  /**
+   * Test to make sure release 1.2.0 support CONCAT
+   */
+  @Test
+  public void testRelease1_2_0() {
+    assertTrue(LayoutVersion.supports(Feature.CONCAT, 
+        Feature.RESERVED_REL1_2_0.lv));
+  }
+  
+  /**
+   * Given feature {@code f}, ensures the layout version of that feature
+   * supports all the features supported by it's ancestor.
+   */
+  private void validateFeatureList(Feature f) {
+    int lv = f.lv;
+    int ancestorLV = f.ancestorLV;
+    EnumSet<Feature> ancestorSet = LayoutVersion.map.get(ancestorLV);
+    assertNotNull(ancestorSet);
+    for (Feature  feature : ancestorSet) {
+      assertTrue("LV " + lv + " does nto support " + feature
+          + " supported by the ancestor LV " + f.ancestorLV,
+          LayoutVersion.supports(feature, lv));
+    }
+  }
+}