HDDS-12897. Enable EmptyLineSeparator checkstyle rule

hadoop-hdds/client/src/main/java/org/apache/hadoop/hdds/scm/ContainerClientMetrics.java

@@ -66,7 +66,6 @@ public final class ContainerClientMetrics {
   @Metric
   private MutableCounterLong flushesDuringWrite;
 
-
   private MutableQuantiles[] listBlockLatency;
   private MutableQuantiles[] getBlockLatency;
   private MutableQuantiles[] getCommittedBlockLengthLatency;

hadoop-hdds/client/src/main/java/org/apache/hadoop/hdds/scm/XceiverClientManager.java

@@ -275,7 +275,6 @@ public long getStaleThreshold(TimeUnit unit) {
       return unit.convert(staleThreshold, MILLISECONDS);
     }
 
-
     public int getMaxSize() {
       return maxSize;
     }

hadoop-hdds/client/src/main/java/org/apache/hadoop/hdds/scm/XceiverClientRatis.java

@@ -239,7 +239,6 @@ private RaftClient getClient() {
     return Objects.requireNonNull(client.get(), "client is null");
   }
 
-
   @VisibleForTesting
   public ConcurrentMap<UUID, Long> getCommitInfoMap() {
     return commitInfoMap;

hadoop-hdds/client/src/main/java/org/apache/hadoop/hdds/scm/client/HddsClientUtils.java

@@ -231,7 +231,6 @@ public static int getMaxOutstandingRequests(ConfigurationSource config) {
         .getMaxOutstandingRequests();
   }
 
-
   // This will return the underlying exception after unwrapping
   // the exception to see if it matches with expected exception
   // list otherwise will return the exception back.

hadoop-hdds/client/src/main/java/org/apache/hadoop/hdds/scm/storage/BlockDataStreamOutput.java

@@ -139,6 +139,7 @@ public class BlockDataStreamOutput implements ByteBufferStreamOutput {
   // buffers for which putBlock is yet to be executed
   private List<StreamBuffer> buffersForPutBlock;
   private boolean isDatastreamPipelineMode;
+
   /**
    * Creates a new BlockDataStreamOutput.
    *
@@ -604,7 +605,6 @@ private void validateResponse(
     }
   }
 
-
   private void setIoException(Throwable e) {
     IOException ioe = getIoException();
     if (ioe == null) {

hadoop-hdds/client/src/main/java/org/apache/hadoop/hdds/scm/storage/BlockOutputStream.java

@@ -819,7 +819,6 @@ void validateResponse(
     }
   }
 
-
   public IOException setIoException(Throwable e) {
     IOException ioe = getIoException();
     if (ioe == null) {
@@ -1245,6 +1244,7 @@ ContainerCommandResponseProto getResponse() {
    */
   private static class FlushRuntimeException extends RuntimeException {
     private final IOException cause;
+
     FlushRuntimeException(IOException cause) {
       this.cause = cause;
     }

hadoop-hdds/client/src/main/java/org/apache/hadoop/hdds/scm/storage/BufferPool.java

@@ -55,7 +55,6 @@ public class BufferPool {
   private final Lock lock = new ReentrantLock();
   private final Condition notFull = lock.newCondition();
 
-
   public static BufferPool empty() {
     return EMPTY;
   }

hadoop-hdds/client/src/main/java/org/apache/hadoop/hdds/scm/storage/ChunkInputStream.java

@@ -675,7 +675,6 @@ private boolean chunkStreamEOF() {
     }
   }
 
-
   /**
    * Release the buffers upto the given index.
    * @param releaseUptoBufferIndex bufferIndex (inclusive) upto which the

hadoop-hdds/client/src/main/java/org/apache/hadoop/hdds/scm/storage/ECBlockOutputStream.java

@@ -64,6 +64,7 @@ public class ECBlockOutputStream extends BlockOutputStream {
 
   private CompletableFuture<ContainerProtos.ContainerCommandResponseProto>
       putBlkRspFuture = null;
+
   /**
    * Creates a new ECBlockOutputStream.
    *

hadoop-hdds/client/src/main/java/org/apache/hadoop/hdds/scm/storage/StreamBuffer.java

@@ -46,7 +46,6 @@ public int position() {
     return buffer.position();
   }
 
-
   public void put(StreamBuffer sb) {
     buffer.put(sb.buffer);
   }

hadoop-hdds/client/src/main/java/org/apache/hadoop/ozone/client/io/ECBlockInputStream.java

@@ -75,6 +75,7 @@ public class ECBlockInputStream extends BlockExtendedInputStream {
   private boolean closed = false;
   private boolean seeked = false;
   private OzoneClientConfig config;
+
   protected ECReplicationConfig getRepConfig() {
     return repConfig;
   }

hadoop-hdds/client/src/test/java/org/apache/hadoop/ozone/client/io/ECStreamTestUtil.java

@@ -212,7 +212,6 @@ public static Map<DatanodeDetails, Integer> createIndexMap(int... idxs) {
     return map;
   }
 
-
   /**
    * A stream factory which can be used in tests to provide TestBlockStream
    * instances.
@@ -357,7 +356,7 @@ public int read(ByteBuffer buf) throws IOException {
         buf.put(data.get());
       }
       return toRead;
-    };
+    }
 
     private void throwError() throws IOException {
       if (errorToThrow != null) {

hadoop-hdds/client/src/test/java/org/apache/hadoop/ozone/client/io/TestECBlockInputStream.java

@@ -642,7 +642,7 @@ public int read(ByteBuffer buf) throws IOException {
       }
       position += toRead;
       return toRead;
-    };
+    }
 
     @Override
     protected int readWithStrategy(ByteReaderStrategy strategy) throws

hadoop-hdds/client/src/test/java/org/apache/hadoop/ozone/client/io/TestECBlockReconstructedInputStream.java

@@ -157,7 +157,6 @@ public void testReadDataByteBufferMultipleStripes() throws IOException {
     }
   }
 
-
   @Test
   public void testReadDataWithUnbuffer() throws IOException {
     // Read buffer is 16kb + 5 bytes so it does not align with stripes exactly
@@ -349,8 +348,6 @@ private void resetAndAdvanceDataGenerator(long position) {
     }
   }
 
-
-
   /**
    * Return a list of num ByteBuffers of the given size.
    * @param num Number of buffers to create

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/HddsUtils.java

@@ -99,7 +99,6 @@
 @InterfaceStability.Stable
 public final class HddsUtils {
 
-
   private static final Logger LOG = LoggerFactory.getLogger(HddsUtils.class);
 
   public static final ByteString REDACTED =

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/JavaUtils.java

@@ -47,7 +47,6 @@ public static boolean isJavaVersionAtMost(int version) {
     return JAVA_SPEC_VER <= version;
   }
 
-
   /**
    * Private constructor.
    */

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/client/DecommissionUtils.java

@@ -45,7 +45,6 @@
 @InterfaceStability.Stable
 public final class DecommissionUtils {
 
-
   private static final Logger LOG = LoggerFactory.getLogger(DecommissionUtils.class);
 
   private DecommissionUtils() {

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/protocol/DatanodeDetails.java

@@ -412,7 +412,6 @@ public Port getStandalonePort() {
     return getPort(Name.STANDALONE);
   }
 
-
   /**
    * Starts building a new DatanodeDetails from the protobuf input.
    *
@@ -679,7 +678,6 @@ public boolean equals(Object obj) {
         id.equals(((DatanodeDetails) obj).id);
   }
 
-
   /**
    * Checks hostname, ipAddress and port of the 2 nodes are the same.
    * @param datanodeDetails dnDetails object to compare with.

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/ratis/RatisHelper.java

@@ -413,7 +413,6 @@ public static void createRaftServerProperties(ConfigurationSource ozoneConf,
     });
   }
 
-
   private static Map<String, String> getDatanodeRatisPrefixProps(
       ConfigurationSource configuration) {
     return configuration.getPropsMatchPrefixAndTrimPrefix(
@@ -531,7 +530,6 @@ static RaftPeer newRaftPeer(RaftPeer peer, RaftPeerId target) {
     return RaftPeer.newBuilder(peer).setPriority(priority).build();
   }
 
-
   /**
    * Use raft client to send admin request, transfer the leadership.
    * 1. Set priority and send setConfiguration request
@@ -647,7 +645,6 @@ public static int calculateAttempts(Duration pollInterval, Duration maxDuration)
     return (int) (max / interval);
   }
 
-
   public static void setFirstElectionTimeoutDuration(
       ConfigurationSource conf, RaftProperties properties, String configKey) {
     long firstElectionTimeout = conf.getTimeDuration(configKey, -1, TimeUnit.MILLISECONDS);

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/ratis/retrypolicy/RequestTypeDependentRetryPolicyCreator.java

@@ -114,6 +114,7 @@ private static ExceptionDependentRetry createExceptionDependentPolicy(
         .setDefaultPolicy(multipleLinearRandomRetry)
         .build();
   }
+
   private static TimeDuration toTimeDuration(Duration duration) {
     return toTimeDuration(duration.toMillis());
   }

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/AddSCMRequest.java

@@ -45,6 +45,7 @@ public HddsProtos.AddScmRequestProto getProtobuf() {
     return HddsProtos.AddScmRequestProto.newBuilder().setClusterId(clusterId)
         .setScmId(scmId).setRatisAddr(ratisAddr).build();
   }
+
   /**
    * Builder for AddSCMRequest.
    */
@@ -53,7 +54,6 @@ public static class Builder {
     private String scmId;
     private String ratisAddr;
 
-
     /**
      * sets the cluster id.
      * @param cid clusterId to be set

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/ScmConfig.java

@@ -151,7 +151,6 @@ public void setKerberosPrincipal(String kerberosPrincipal) {
     this.principal = kerberosPrincipal;
   }
 
-
   public void setKerberosKeytab(String kerberosKeytab) {
     this.keytab = kerberosKeytab;
   }

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/ScmConfigKeys.java

@@ -445,7 +445,6 @@ public final class ScmConfigKeys {
   public static final String OZONE_SCM_PIPELINE_SCRUB_INTERVAL_DEFAULT =
       "150s";
 
-
   // Allow SCM to auto create factor ONE ratis pipeline.
   public static final String OZONE_SCM_PIPELINE_AUTO_CREATE_FACTOR_ONE =
       "ozone.scm.pipeline.creation.auto.factor.one";
@@ -497,7 +496,6 @@ public final class ScmConfigKeys {
       "ozone.scm.ca.list.retry.interval";
   public static final long OZONE_SCM_CA_LIST_RETRY_INTERVAL_DEFAULT = 10;
 
-
   public static final String OZONE_SCM_EVENT_PREFIX = "ozone.scm.event.";
 
   public static final String OZONE_SCM_EVENT_CONTAINER_REPORT_THREAD_POOL_SIZE =

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/XceiverClientSpi.java

@@ -149,6 +149,7 @@ public static IOException getIOExceptionForSendCommand(
     return new IOException("Failed to execute command "
         + HddsUtils.processForDebug(request), e);
   }
+
   /**
    * Sends a given command to server gets a waitable future back.
    *

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/container/common/helpers/ContainerWithPipeline.java

@@ -66,7 +66,6 @@ public HddsProtos.ContainerWithPipeline getProtobuf(int clientVersion)
     return builder.build();
   }
 
-
   @Override
   public String toString() {
     return containerInfo.toString() + " | " + pipeline.toString();

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/container/common/helpers/ExcludeList.java

@@ -44,7 +44,6 @@ public class ExcludeList {
   private long expiryTime = 0;
   private final Clock clock;
 
-
   public ExcludeList() {
     clock = Clock.system(ZoneOffset.UTC);
   }

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/net/InnerNodeImpl.java

@@ -677,6 +677,7 @@ private Map<String, Integer> getExcludedScopeNodeCount(
     }
     return nodeCounts;
   }
+
   protected static class Factory implements InnerNode.Factory<InnerNodeImpl> {
     protected Factory() { }
 

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/net/NetUtils.java

@@ -36,6 +36,7 @@ public final class NetUtils {
   private NetUtils() {
     // Prevent instantiation
   }
+
   /**
    * Normalize a path by stripping off any trailing.
    * {@link NetConstants#PATH_SEPARATOR}
@@ -74,7 +75,6 @@ public static int locationToDepth(String location) {
         newLocation.split(NetConstants.PATH_SEPARATOR_STR).length;
   }
 
-
   /**
    *  Remove node from mutableExcludedNodes if it's covered by excludedScope.
    *  Please noted that mutableExcludedNodes content might be changed after the

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/net/NetworkTopology.java

@@ -27,10 +27,12 @@ public interface NetworkTopology {
   /** Exception for invalid network topology detection. */
   class InvalidTopologyException extends RuntimeException {
     private static final long serialVersionUID = 1L;
+
     public InvalidTopologyException(String msg) {
       super(msg);
     }
   }
+
   /**
    * Add a leaf node. This will be called when a new datanode is added.
    * @param node node to be added; can be null

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/net/NodeImpl.java

@@ -248,6 +248,7 @@ public boolean isAncestor(String nodePath) {
         NetUtils.addSuffix(nodePath).startsWith(
             NetUtils.addSuffix(this.getNetworkFullPath()));
   }
+
   @Override
   public boolean isDescendant(Node node) {
     if (node == null) {

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/net/NodeSchema.java

@@ -133,6 +133,7 @@ public void setDefaultName(String name) {
   public int getCost() {
     return this.cost;
   }
+
   public void setCost(int cost) {
     this.cost = cost;
   }
@@ -170,6 +171,7 @@ public String toString() {
     public int getCost() {
       return cost;
     }
+
     public static LayerType getType(String typeStr) {
       for (LayerType type: LayerType.values()) {
         if (typeStr.equalsIgnoreCase(type.toString())) {

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/net/NodeSchemaLoader.java

@@ -66,6 +66,7 @@ public final class NodeSchemaLoader {
 
   private static final int LAYOUT_VERSION = 1;
   private static volatile NodeSchemaLoader instance = null;
+
   private NodeSchemaLoader() { }
 
   public static NodeSchemaLoader getInstance() {

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/pipeline/Pipeline.java

@@ -223,7 +223,6 @@ public boolean sameDatanodes(Pipeline pipeline) {
     return getNodeSet().equals(pipeline.getNodeSet());
   }
 
-
   /**
    * Return the replica index of the specific datanode in the datanode set.
    * <p>
@@ -604,6 +603,7 @@ public Builder setLeaderId(UUID leaderId1) {
       this.leaderId = leaderId1;
       return this;
     }
+
     public Builder setNodes(List<DatanodeDetails> nodes) {
       this.nodeStatus = new LinkedHashMap<>();
       nodes.forEach(node -> nodeStatus.put(node, -1L));
@@ -642,7 +642,6 @@ public Builder setSuggestedLeaderId(UUID uuid) {
       return this;
     }
 
-
     public Builder setReplicaIndexes(Map<DatanodeDetails, Integer> indexes) {
       this.replicaIndexes = indexes == null ? ImmutableMap.of() : ImmutableMap.copyOf(indexes);
       return this;

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/protocolPB/ContainerCommandResponseBuilders.java

@@ -168,6 +168,7 @@ public static ContainerCommandResponseProto getListBlockResponse(
         .setListBlock(builder)
         .build();
   }
+
   /**
    * Returns successful getCommittedBlockLength Response.
    * @param msg - Request.
@@ -281,6 +282,7 @@ public static ContainerCommandResponseProto getGetSmallFileResponseSuccess(
         .setGetSmallFile(getSmallFile)
         .build();
   }
+
   /**
    * Returns a ReadContainer Response.
    *

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/storage/ContainerProtocolCalls.java

@@ -563,6 +563,7 @@ public static void createContainer(XceiverClientSpi client, long containerID,
       String encodedToken) throws IOException {
     createContainer(client, containerID, encodedToken, null, 0);
   }
+
   /**
    * createContainer call that creates a container on the datanode.
    * @param client  - client