HDFS-8962. Clean up checkstyle warnings in o.a.h.hdfs.DfsClientConf. Contributed by Mingliang Liu.

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/HdfsClientConfigKeys.java

@@ -117,7 +117,7 @@ public interface HdfsClientConfigKeys {
       "dfs.datanode.hdfs-blocks-metadata.enabled";
   boolean DFS_HDFS_BLOCKS_METADATA_ENABLED_DEFAULT = false;
 
-  static final String REPLICA_ACCESSOR_BUILDER_CLASSES_KEY =
+  String REPLICA_ACCESSOR_BUILDER_CLASSES_KEY =
       PREFIX + "replica.accessor.builder.classes";
 
   /** dfs.client.retry configuration properties */

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/impl/DfsClientConf.java

@@ -262,7 +262,7 @@ public class DfsClientConf {
       return Collections.emptyList();
     }
     ArrayList<Class<? extends ReplicaAccessorBuilder>> classes =
-        new ArrayList<Class<? extends ReplicaAccessorBuilder>>();
+        new ArrayList<>();
     ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
     for (String className: classNames) {
       try {
@@ -778,35 +778,33 @@ public class DfsClientConf {
     }
 
     public String confAsString() {
-      StringBuilder builder = new StringBuilder();
-      builder.append("shortCircuitStreamsCacheSize = ").
-        append(shortCircuitStreamsCacheSize).
-        append(", shortCircuitStreamsCacheExpiryMs = ").
-        append(shortCircuitStreamsCacheExpiryMs).
-        append(", shortCircuitMmapCacheSize = ").
-        append(shortCircuitMmapCacheSize).
-        append(", shortCircuitMmapCacheExpiryMs = ").
-        append(shortCircuitMmapCacheExpiryMs).
-        append(", shortCircuitMmapCacheRetryTimeout = ").
-        append(shortCircuitMmapCacheRetryTimeout).
-        append(", shortCircuitCacheStaleThresholdMs = ").
-        append(shortCircuitCacheStaleThresholdMs).
-        append(", socketCacheCapacity = ").
-        append(socketCacheCapacity).
-        append(", socketCacheExpiry = ").
-        append(socketCacheExpiry).
-        append(", shortCircuitLocalReads = ").
-        append(shortCircuitLocalReads).
-        append(", useLegacyBlockReaderLocal = ").
-        append(useLegacyBlockReaderLocal).
-        append(", domainSocketDataTraffic = ").
-        append(domainSocketDataTraffic).
-        append(", shortCircuitSharedMemoryWatcherInterruptCheckMs = ").
-        append(shortCircuitSharedMemoryWatcherInterruptCheckMs).
-        append(", keyProviderCacheExpiryMs = ").
-        append(keyProviderCacheExpiryMs);
-
-      return builder.toString();
+
+      return "shortCircuitStreamsCacheSize = "
+          + shortCircuitStreamsCacheSize
+          + ", shortCircuitStreamsCacheExpiryMs = "
+          + shortCircuitStreamsCacheExpiryMs
+          + ", shortCircuitMmapCacheSize = "
+          + shortCircuitMmapCacheSize
+          + ", shortCircuitMmapCacheExpiryMs = "
+          + shortCircuitMmapCacheExpiryMs
+          + ", shortCircuitMmapCacheRetryTimeout = "
+          + shortCircuitMmapCacheRetryTimeout
+          + ", shortCircuitCacheStaleThresholdMs = "
+          + shortCircuitCacheStaleThresholdMs
+          + ", socketCacheCapacity = "
+          + socketCacheCapacity
+          + ", socketCacheExpiry = "
+          + socketCacheExpiry
+          + ", shortCircuitLocalReads = "
+          + shortCircuitLocalReads
+          + ", useLegacyBlockReaderLocal = "
+          + useLegacyBlockReaderLocal
+          + ", domainSocketDataTraffic = "
+          + domainSocketDataTraffic
+          + ", shortCircuitSharedMemoryWatcherInterruptCheckMs = "
+          + shortCircuitSharedMemoryWatcherInterruptCheckMs
+          + ", keyProviderCacheExpiryMs = "
+          + keyProviderCacheExpiryMs;
     }
   }
 }

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

@@ -505,6 +505,9 @@ Release 2.8.0 - UNRELEASED
     HDFS-8248. Store INodeId instead of the INodeFile object in
     BlockInfoContiguous. (wheat9)
 
+    HDFS-8962. Clean up checkstyle warnings in o.a.h.hdfs.DfsClientConf.
+    (Mingliang Liu via wheat9)
+
   OPTIMIZATIONS
 
     HDFS-8026. Trace FSOutputSummer#writeChecksumChunks rather than

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderFactory.java

@@ -56,7 +56,6 @@ import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitReplica;
 import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitReplicaInfo;
 import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.Slot;
 import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.SlotId;
-import org.apache.hadoop.io.ByteWritable;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.ipc.RemoteException;
 import org.apache.hadoop.net.unix.DomainSocket;
@@ -328,10 +327,8 @@ public class BlockReaderFactory implements ShortCircuitReplicaCreator {
    *             If there was another problem.
    */
   public BlockReader build() throws IOException {
-    BlockReader reader = null;
-
     Preconditions.checkNotNull(configuration);
-    reader = tryToCreateExternalBlockReader();
+    BlockReader reader = tryToCreateExternalBlockReader();
     if (reader != null) {
       return reader;
     }
@@ -432,7 +429,7 @@ public class BlockReaderFactory implements ShortCircuitReplicaCreator {
             "disableLegacyBlockReaderLocal is set.", this);
       return null;
     }
-    IOException ioe = null;
+    IOException ioe;
     try {
       return BlockReaderLocalLegacy.newBlockReader(conf,
           userGroupInformation, configuration, fileName, block, token,

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataXceiver.java

@@ -703,10 +703,10 @@ class DataXceiver extends Receiver implements Runnable {
         mirrorTarget = NetUtils.createSocketAddr(mirrorNode);
         mirrorSock = datanode.newSocket();
         try {
-          int timeoutValue = dnConf.socketTimeout
-              + (HdfsConstants.READ_TIMEOUT_EXTENSION * targets.length);
-          int writeTimeout = dnConf.socketWriteTimeout + 
-                      (HdfsConstants.WRITE_TIMEOUT_EXTENSION * targets.length);
+          int timeoutValue = dnConf.socketTimeout +
+              (HdfsConstants.READ_TIMEOUT_EXTENSION * targets.length);
+          int writeTimeout = dnConf.socketWriteTimeout +
+              (HdfsConstants.WRITE_TIMEOUT_EXTENSION * targets.length);
           NetUtils.connect(mirrorSock, mirrorTarget, timeoutValue);
           mirrorSock.setSoTimeout(timeoutValue);
           mirrorSock.setSendBufferSize(HdfsConstants.DEFAULT_DATA_SOCKET_SIZE);

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDataTransferProtocol.java

@@ -110,7 +110,7 @@ public class TestDataTransferProtocol {
       sock = new Socket();
       sock.connect(dnAddr, HdfsConstants.READ_TIMEOUT);
       sock.setSoTimeout(HdfsConstants.READ_TIMEOUT);
-      
+
       OutputStream out = sock.getOutputStream();
       // Should we excuse 
       byte[] retBuf = new byte[recvBuf.size()];

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDistributedFileSystem.java

@@ -39,6 +39,7 @@ import java.net.URI;
 import java.security.PrivilegedExceptionAction;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.EnumSet;
 import java.util.HashSet;
 import java.util.List;
@@ -97,7 +98,7 @@ import com.google.common.collect.Lists;
 public class TestDistributedFileSystem {
   private static final Random RAN = new Random();
 
-  {
+  static {
     ((Log4JLogger)DFSClient.LOG).getLogger().setLevel(Level.ALL);
   }
 
@@ -108,16 +109,17 @@ public class TestDistributedFileSystem {
   private HdfsConfiguration getTestConfiguration() {
     HdfsConfiguration conf;
     if (noXmlDefaults) {
-       conf = new HdfsConfiguration(false);
-       String namenodeDir = new File(MiniDFSCluster.getBaseDirectory(), "name").getAbsolutePath();
-       conf.set(DFSConfigKeys.DFS_NAMENODE_NAME_DIR_KEY, namenodeDir);
-       conf.set(DFSConfigKeys.DFS_NAMENODE_EDITS_DIR_KEY, namenodeDir);     
+      conf = new HdfsConfiguration(false);
+      String namenodeDir = new File(MiniDFSCluster.getBaseDirectory(), "name").
+          getAbsolutePath();
+      conf.set(DFSConfigKeys.DFS_NAMENODE_NAME_DIR_KEY, namenodeDir);
+      conf.set(DFSConfigKeys.DFS_NAMENODE_EDITS_DIR_KEY, namenodeDir);
     } else {
-       conf = new HdfsConfiguration();
+      conf = new HdfsConfiguration();
     }
     if (dualPortTesting) {
       conf.set(DFSConfigKeys.DFS_NAMENODE_SERVICE_RPC_ADDRESS_KEY,
-              "localhost:0");
+          "localhost:0");
     }
     conf.setLong(DFSConfigKeys.DFS_NAMENODE_MIN_BLOCK_SIZE_KEY, 0);
 
@@ -133,14 +135,17 @@ public class TestDistributedFileSystem {
       FileSystem fileSys = cluster.getFileSystem();
       fileSys.getDelegationToken("");
     } finally {
-      cluster.shutdown();
+      if (cluster != null) {
+        cluster.shutdown();
+      }
     }
   }
 
   @Test
   public void testFileSystemCloseAll() throws Exception {
     Configuration conf = getTestConfiguration();
-    MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).numDataNodes(0).build();
+    MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).numDataNodes(0).
+        build();
     URI address = FileSystem.getDefaultUri(conf);
 
     try {
@@ -503,7 +508,8 @@ public class TestDistributedFileSystem {
   }
   
   /** Checks statistics. -1 indicates do not check for the operations */
-  private void checkStatistics(FileSystem fs, int readOps, int writeOps, int largeReadOps) {
+  private void checkStatistics(FileSystem fs, int readOps, int writeOps,
+      int largeReadOps) {
     assertEquals(readOps, DFSTestUtil.getStatistics(fs).getReadOps());
     assertEquals(writeOps, DFSTestUtil.getStatistics(fs).getWriteOps());
     assertEquals(largeReadOps, DFSTestUtil.getStatistics(fs).getLargeReadOps());
@@ -520,7 +526,8 @@ public class TestDistributedFileSystem {
     final Configuration conf = getTestConfiguration();
     conf.setBoolean(HdfsClientConfigKeys.DFS_WEBHDFS_ENABLED_KEY, true);
 
-    final MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).numDataNodes(2).build();
+    final MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf)
+        .numDataNodes(2).build();
     final FileSystem hdfs = cluster.getFileSystem();
 
     final String nnAddr = conf.get(DFSConfigKeys.DFS_NAMENODE_HTTP_ADDRESS_KEY);
@@ -571,7 +578,8 @@ public class TestDistributedFileSystem {
 
     final Path dir = new Path("/filechecksum");
     final int block_size = 1024;
-    final int buffer_size = conf.getInt(CommonConfigurationKeys.IO_FILE_BUFFER_SIZE_KEY, 4096);
+    final int buffer_size = conf.getInt(
+        CommonConfigurationKeys.IO_FILE_BUFFER_SIZE_KEY, 4096);
     conf.setInt(HdfsClientConfigKeys.DFS_BYTES_PER_CHECKSUM_KEY, 512);
 
     //try different number of blocks
@@ -607,14 +615,15 @@ public class TestDistributedFileSystem {
       System.out.println("webhdfsfoocs=" + webhdfsfoocs);
 
       final Path webhdfsqualified = new Path(webhdfsuri + dir, "foo" + n);
-      final FileChecksum webhdfs_qfoocs = webhdfs.getFileChecksum(webhdfsqualified);
+      final FileChecksum webhdfs_qfoocs =
+          webhdfs.getFileChecksum(webhdfsqualified);
       System.out.println("webhdfs_qfoocs=" + webhdfs_qfoocs);
 
       //create a zero byte file
       final Path zeroByteFile = new Path(dir, "zeroByteFile" + n);
       {
-        final FSDataOutputStream out = hdfs.create(zeroByteFile, false, buffer_size,
-            (short)2, block_size);
+        final FSDataOutputStream out = hdfs.create(zeroByteFile, false,
+            buffer_size, (short)2, block_size);
         out.close();
       }
 
@@ -743,9 +752,7 @@ public class TestDistributedFileSystem {
         String[] ids = loc.getStorageIds();
         // Run it through a set to deduplicate, since there should be no dupes
         Set<String> storageIds = new HashSet<>();
-        for (String id: ids) {
-          storageIds.add(id);
-        }
+        Collections.addAll(storageIds, ids);
         assertEquals("Unexpected num storage ids", repl, storageIds.size());
         // Make sure these are all valid storage IDs
         assertTrue("Unknown storage IDs found!", dnStorageIds.containsAll
@@ -1043,9 +1050,7 @@ public class TestDistributedFileSystem {
       output.close();
       assertTrue("File status should be closed", fs.isFileClosed(file));
     } finally {
-      if (cluster != null) {
-        cluster.shutdown();
-      }
+      cluster.shutdown();
     }
   }
   
@@ -1060,8 +1065,9 @@ public class TestDistributedFileSystem {
       final Path relative = new Path("relative");
       fs.create(new Path(relative, "foo")).close();
   
-      final List<LocatedFileStatus> retVal = new ArrayList<LocatedFileStatus>();
-      final RemoteIterator<LocatedFileStatus> iter = fs.listFiles(relative, true);
+      final List<LocatedFileStatus> retVal = new ArrayList<>();
+      final RemoteIterator<LocatedFileStatus> iter =
+          fs.listFiles(relative, true);
       while (iter.hasNext()) {
         retVal.add(iter.next());
       }
@@ -1076,7 +1082,7 @@ public class TestDistributedFileSystem {
     final int timeout = 1000;
     final Configuration conf = new HdfsConfiguration();
     conf.setInt(HdfsClientConfigKeys.DFS_CLIENT_SOCKET_TIMEOUT_KEY, timeout);
-    
+
     // only need cluster to create a dfs client to get a peer
     final MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build();
     try {

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestCachingStrategy.java

@@ -51,7 +51,7 @@ public class TestCachingStrategy {
   private static final Log LOG = LogFactory.getLog(TestCachingStrategy.class);
   private static final int MAX_TEST_FILE_LEN = 1024 * 1024;
   private static final int WRITE_PACKET_SIZE = HdfsClientConfigKeys.DFS_CLIENT_WRITE_PACKET_SIZE_DEFAULT;
-  
+
   private final static TestRecordingCacheTracker tracker =
       new TestRecordingCacheTracker();
 
@@ -113,7 +113,7 @@ public class TestCachingStrategy {
   }
 
   private static class TestRecordingCacheTracker extends CacheManipulator {
-    private final Map<String, Stats> map = new TreeMap<String, Stats>();
+    private final Map<String, Stats> map = new TreeMap<>();
 
     @Override
     public void posixFadviseIfPossible(String name,
@@ -365,8 +365,6 @@ public class TestCachingStrategy {
       
       // read file
       readHdfsFile(fs, new Path(TEST_PATH), Long.MAX_VALUE, false);
-      // verify that we dropped everything from the cache.
-      Assert.assertNull(stats);
     } finally {
       if (cluster != null) {
         cluster.shutdown();
@@ -389,13 +387,10 @@ public class TestCachingStrategy {
       FileSystem fs = cluster.getFileSystem();
       createHdfsFile(fs, new Path(TEST_PATH), TEST_PATH_LEN, false);
       // verify that we can seek after setDropBehind
-      FSDataInputStream fis = fs.open(new Path(TEST_PATH));
-      try {
+      try (FSDataInputStream fis = fs.open(new Path(TEST_PATH))) {
         Assert.assertTrue(fis.read() != -1); // create BlockReader
         fis.setDropBehind(false); // clear BlockReader
         fis.seek(2); // seek
-      } finally {
-        fis.close();
       }
     } finally {
       if (cluster != null) {

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/shortcircuit/TestShortCircuitCache.java

@@ -71,7 +71,6 @@ import org.junit.Assert;
 import org.junit.Assume;
 import org.junit.Test;
 import org.mockito.Mockito;
-import org.mockito.internal.util.reflection.Whitebox;
 import org.mockito.invocation.InvocationOnMock;
 import org.mockito.stubbing.Answer;
 
@@ -269,7 +268,7 @@ public class TestShortCircuitCache {
     }
     // The last two replicas should still be cached.
     for (int i = 1; i < pairs.length; i++) {
-      final Integer iVal = new Integer(i);
+      final Integer iVal = i;
       replicaInfos[i] = cache.fetchOrCreate(
           new ExtendedBlockId(i, "test_bp1"),
             new ShortCircuitReplicaCreator() {
@@ -322,7 +321,7 @@ public class TestShortCircuitCache {
     };
     final long HOUR_IN_MS = 60 * 60 * 1000;
     for (int i = 0; i < pairs.length; i++) {
-      final Integer iVal = new Integer(i);
+      final Integer iVal = i;
       final ExtendedBlockId key = new ExtendedBlockId(i, "test_bp1");
       replicaInfos[i] = cache.fetchOrCreate(key,
           new ShortCircuitReplicaCreator() {

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/shortcircuit/TestShortCircuitLocalRead.java

@@ -94,17 +94,17 @@ public class TestShortCircuitLocalRead {
   public void before() {
     Assume.assumeThat(DomainSocket.getLoadingFailureReason(), equalTo(null));
   }
-  
+
   static final long seed = 0xDEADBEEFL;
   static final int blockSize = 5120;
   final boolean simulatedStorage = false;
-  
+
   // creates a file but does not close it
   static FSDataOutputStream createFile(FileSystem fileSys, Path name, int repl)
       throws IOException {
     FSDataOutputStream stm = fileSys.create(name, true,
-                                            fileSys.getConf().getInt("io.file.buffer.size", 4096),
-                                            (short)repl, blockSize);
+        fileSys.getConf().getInt("io.file.buffer.size", 4096),
+        (short)repl, blockSize);
     return stm;
   }
 
@@ -112,19 +112,20 @@ public class TestShortCircuitLocalRead {
       String message) {
     checkData(actual, from, expected, actual.length, message);
   }
-  
-  static private void checkData(byte[] actual, int from, byte[] expected, int len,
-      String message) {
+
+  static private void checkData(byte[] actual, int from, byte[] expected,
+      int len, String message) {
     for (int idx = 0; idx < len; idx++) {
       if (expected[from + idx] != actual[idx]) {
-        Assert.fail(message + " byte " + (from + idx) + " differs. expected "
-            + expected[from + idx] + " actual " + actual[idx] +
-            "\nexpected: " + StringUtils.byteToHexString(expected, from, from + len) +
+        Assert.fail(message + " byte " + (from + idx) + " differs. expected " +
+            expected[from + idx] + " actual " + actual[idx] +
+            "\nexpected: " +
+            StringUtils.byteToHexString(expected, from, from + len) +
             "\nactual:   " + StringUtils.byteToHexString(actual, 0, len));
       }
     }
   }
-  
+
   private static String getCurrentUser() throws IOException {
     return UserGroupInformation.getCurrentUser().getShortUserName();
   }
@@ -140,7 +141,7 @@ public class TestShortCircuitLocalRead {
     if (legacyShortCircuitFails) {
       assertFalse(getClientContext.getDisableLegacyBlockReaderLocal());
     }
-    
+
     FSDataInputStream stm = fs.open(name);
     byte[] actual = new byte[expected.length-readOffset];
     stm.readFully(readOffset, actual);
@@ -165,7 +166,7 @@ public class TestShortCircuitLocalRead {
       nread += nbytes;
     }
     checkData(actual, readOffset, expected, "Read 3");
-    
+
     if (legacyShortCircuitFails) {
       assertTrue(getClientContext.getDisableLegacyBlockReaderLocal());
     }
@@ -179,7 +180,7 @@ public class TestShortCircuitLocalRead {
     alt.get(arr);
     return arr;
   }
-  
+
   /** Check the file content, reading as user {@code readingUser} */
   static void checkFileContentDirect(URI uri, Path name, byte[] expected,
       int readOffset, String readingUser, Configuration conf,
@@ -191,7 +192,7 @@ public class TestShortCircuitLocalRead {
     if (legacyShortCircuitFails) {
       assertTrue(clientContext.getDisableLegacyBlockReaderLocal());
     }
-    
+
     HdfsDataInputStream stm = (HdfsDataInputStream)fs.open(name);
 
     ByteBuffer actual = ByteBuffer.allocateDirect(expected.length - readOffset);
@@ -239,7 +240,7 @@ public class TestShortCircuitLocalRead {
     doTestShortCircuitReadImpl(ignoreChecksum, size, readOffset,
         null, getCurrentUser(), false);
   }
-  
+
   /**
    * Test that file data can be read by reading the block file
    * directly from the local store.
@@ -272,15 +273,15 @@ public class TestShortCircuitLocalRead {
     try {
       // check that / exists
       Path path = new Path("/");
-      assertTrue("/ should be a directory", fs.getFileStatus(path)
-          .isDirectory() == true);
-      
+      assertTrue("/ should be a directory",
+          fs.getFileStatus(path).isDirectory());
+
       byte[] fileData = AppendTestUtil.randomBytes(seed, size);
       Path file1 = fs.makeQualified(new Path("filelocal.dat"));
       FSDataOutputStream stm = createFile(fs, file1, 1);
       stm.write(fileData);
       stm.close();
-      
+
       URI uri = cluster.getURI();
       checkFileContent(uri, file1, fileData, readOffset, readingUser, conf,
           legacyShortCircuitFails);
@@ -301,7 +302,7 @@ public class TestShortCircuitLocalRead {
   public void testFileLocalReadChecksum() throws Exception {
     doTestShortCircuitRead(false, 3*blockSize+100, 0);
   }
-  
+
   @Test(timeout=60000)
   public void testSmallFileLocalRead() throws Exception {
     doTestShortCircuitRead(false, 13, 0);
@@ -309,7 +310,7 @@ public class TestShortCircuitLocalRead {
     doTestShortCircuitRead(true, 13, 0);
     doTestShortCircuitRead(true, 13, 5);
   }
-  
+
   @Test(timeout=60000)
   public void testLocalReadLegacy() throws Exception {
     doTestShortCircuitReadLegacy(true, 13, 0, getCurrentUser(),
@@ -325,13 +326,13 @@ public class TestShortCircuitLocalRead {
   public void testLocalReadFallback() throws Exception {
     doTestShortCircuitReadLegacy(true, 13, 0, getCurrentUser(), "notallowed", true);
   }
-  
+
   @Test(timeout=60000)
   public void testReadFromAnOffset() throws Exception {
     doTestShortCircuitRead(false, 3*blockSize+100, 777);
     doTestShortCircuitRead(true, 3*blockSize+100, 777);
   }
-  
+
   @Test(timeout=60000)
   public void testLongFile() throws Exception {
     doTestShortCircuitRead(false, 10*blockSize+100, 777);
@@ -348,7 +349,7 @@ public class TestShortCircuitLocalRead {
       }
     });
   }
-  
+
   @Test(timeout=10000)
   public void testDeprecatedGetBlockLocalPathInfoRpc() throws IOException {
     final Configuration conf = new Configuration();
@@ -399,18 +400,18 @@ public class TestShortCircuitLocalRead {
     try {
       // check that / exists
       Path path = new Path("/");
-      assertTrue("/ should be a directory", fs.getFileStatus(path)
-          .isDirectory() == true);
-      
+      assertTrue("/ should be a directory",
+          fs.getFileStatus(path).isDirectory());
+
       byte[] fileData = AppendTestUtil.randomBytes(seed, size*3);
       // create a new file in home directory. Do not close it.
       Path file1 = new Path("filelocal.dat");
       FSDataOutputStream stm = createFile(fs, file1, 1);
-  
+
       // write to file
       stm.write(fileData);
       stm.close();
-      
+
       // now test the skip function
       FSDataInputStream instm = fs.open(file1);
       byte[] actual = new byte[fileData.length];
@@ -421,7 +422,6 @@ public class TestShortCircuitLocalRead {
       instm.seek(skipped);
       nread = instm.read(actual, (int)(skipped + nread), 3);
       instm.close();
-        
     } finally {
       fs.close();
       cluster.shutdown();
@@ -443,7 +443,7 @@ public class TestShortCircuitLocalRead {
     final long RANDOM_SEED2 = 4568L;
     FSDataInputStream fsIn = null;
     final int TEST_LENGTH = 3456;
-    
+
     try {
       cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1).build();
       cluster.waitActive();
@@ -470,14 +470,11 @@ public class TestShortCircuitLocalRead {
       File dataFile = cluster.getBlockFile(0, block);
       cluster.shutdown();
       cluster = null;
-      RandomAccessFile raf = null;
-      try {
-        raf = new RandomAccessFile(dataFile, "rw");
+      try (RandomAccessFile raf = new RandomAccessFile(dataFile, "rw")) {
         raf.setLength(0);
-      } finally {
-        if (raf != null) raf.close();
       }
-      cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1).format(false).build();
+      cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1).format(false)
+          .build();
       cluster.waitActive();
       fs = cluster.getFileSystem();
       fsIn = fs.open(TEST_PATH);
@@ -509,7 +506,7 @@ public class TestShortCircuitLocalRead {
       if (cluster != null) cluster.shutdown();
     }
   }
-     
+
   /**
    * Test to run benchmarks between short circuit read vs regular read with
    * specified number of threads simultaneously reading.
@@ -535,16 +532,16 @@ public class TestShortCircuitLocalRead {
         "/tmp/TestShortCircuitLocalRead._PORT");
     conf.setBoolean(HdfsClientConfigKeys.Read.ShortCircuit.SKIP_CHECKSUM_KEY,
         checksum);
-    
-    //Override fileSize and DATA_TO_WRITE to much larger values for benchmark test
+
+    // Override fileSize and DATA_TO_WRITE to much larger values for benchmark test
     int fileSize = 1000 * blockSize + 100; // File with 1000 blocks
     final byte [] dataToWrite = AppendTestUtil.randomBytes(seed, fileSize);
-    
+
     // create a new file in home directory. Do not close it.
     final Path file1 = new Path("filelocal.dat");
     final FileSystem fs = FileSystem.get(conf);
     FSDataOutputStream stm = createFile(fs, file1, 1);
-    
+
     stm.write(dataToWrite);
     stm.close();
 
@@ -580,8 +577,10 @@ public class TestShortCircuitLocalRead {
   }
 
   @Test(timeout=60000)
-  public void testReadWithRemoteBlockReader() throws IOException, InterruptedException {
-    doTestShortCircuitReadWithRemoteBlockReader(true, 3*blockSize+100, getCurrentUser(), 0, false);
+  public void testReadWithRemoteBlockReader()
+      throws IOException, InterruptedException {
+    doTestShortCircuitReadWithRemoteBlockReader(true, 3 * blockSize + 100,
+        getCurrentUser(), 0, false);
   }
 
   /**
@@ -589,8 +588,9 @@ public class TestShortCircuitLocalRead {
    * through RemoteBlockReader
    * @throws IOException
   */
-  public void doTestShortCircuitReadWithRemoteBlockReader(boolean ignoreChecksum, int size, String shortCircuitUser,
-                                                          int readOffset, boolean shortCircuitFails) throws IOException, InterruptedException {
+  public void doTestShortCircuitReadWithRemoteBlockReader(boolean ignoreChecksum,
+      int size, String shortCircuitUser, int readOffset,
+      boolean shortCircuitFails) throws IOException, InterruptedException {
     Configuration conf = new Configuration();
     conf.setBoolean(HdfsClientConfigKeys.DFS_CLIENT_USE_LEGACY_BLOCKREADER, true);
     conf.setBoolean(HdfsClientConfigKeys.Read.ShortCircuit.KEY, true);
@@ -601,8 +601,7 @@ public class TestShortCircuitLocalRead {
     // check that / exists
     Path path = new Path("/");
     URI uri = cluster.getURI();
-    assertTrue("/ should be a directory", fs.getFileStatus(path)
-                .isDirectory() == true);
+    assertTrue("/ should be a directory", fs.getFileStatus(path).isDirectory());
 
     byte[] fileData = AppendTestUtil.randomBytes(seed, size);
     Path file1 = new Path("filelocal.dat");
@@ -627,7 +626,7 @@ public class TestShortCircuitLocalRead {
   }
 
   private boolean checkUnsupportedMethod(FileSystem fs, Path file,
-                                           byte[] expected, int readOffset) throws IOException {
+      byte[] expected, int readOffset) throws IOException {
     HdfsDataInputStream stm = (HdfsDataInputStream)fs.open(file);
     ByteBuffer actual = ByteBuffer.allocateDirect(expected.length - readOffset);
     IOUtils.skipFully(stm, readOffset);
@@ -639,5 +638,4 @@ public class TestShortCircuitLocalRead {
     return false;
   }
 
-
 }