HDFS-6938. Cleanup javac warnings in FSNamesystem. Contributed by Charles Lamb.

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

@@ -647,6 +647,8 @@ Release 2.6.0 - UNRELEASED
 
     HDFS-6892. Add XDR packaging method for each NFS request (brandonli)
 
+    HDFS-6938. Cleanup javac warnings in FSNamesystem (Charles Lamb via wheat9)
+
 Release 2.5.1 - UNRELEASED
 
   INCOMPATIBLE CHANGES

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java

@@ -106,7 +106,6 @@ import java.lang.management.ManagementFactory;
 import java.net.InetAddress;
 import java.net.URI;
 import java.security.GeneralSecurityException;
-import java.security.NoSuchAlgorithmException;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
@@ -120,7 +119,6 @@ import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
-import java.util.UUID;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.locks.Condition;
 import java.util.concurrent.locks.ReentrantLock;
@@ -137,8 +135,6 @@ import org.apache.hadoop.HadoopIllegalArgumentException;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.crypto.CipherSuite;
-import org.apache.hadoop.crypto.CryptoCodec;
-import org.apache.hadoop.crypto.key.KeyProvider;
 import org.apache.hadoop.crypto.key.KeyProviderCryptoExtension;
 import org.apache.hadoop.fs.BatchedRemoteIterator.BatchedListEntries;
 import org.apache.hadoop.fs.CacheFlag;
@@ -182,7 +178,6 @@ import org.apache.hadoop.hdfs.protocol.ClientProtocol;
 import org.apache.hadoop.hdfs.protocol.DatanodeID;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.DirectoryListing;
-import org.apache.hadoop.hdfs.protocol.EncryptionZone;
 import org.apache.hadoop.hdfs.protocol.EncryptionZoneWithId;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants;
@@ -543,9 +538,6 @@ public class FSNamesystem implements Namesystem, FSClusterStats,
   private final NNConf nnConf;
 
   private KeyProviderCryptoExtension provider = null;
-  private KeyProvider.Options providerOptions = null;
-
-  private final CryptoCodec codec;
 
   private volatile boolean imageLoaded = false;
   private final Condition cond;
@@ -772,8 +764,6 @@ public class FSNamesystem implements Namesystem, FSClusterStats,
     } else {
       LOG.info("Found KeyProvider: " + provider.toString());
     }
-    providerOptions = KeyProvider.options(conf);
-    this.codec = CryptoCodec.getInstance(conf);
     if (conf.getBoolean(DFS_NAMENODE_AUDIT_LOG_ASYNC_KEY,
                         DFS_NAMENODE_AUDIT_LOG_ASYNC_DEFAULT)) {
       LOG.info("Enabling async auditlog");