HDDS-12907. Enable FieldDeclarationsShouldBeAtStartOfClass PMD rule

dev-support/pmd/pmd-ruleset.xml

@@ -42,5 +42,12 @@
   <rule ref="category/java/performance.xml/StringInstantiation"/>
   <rule ref="category/java/performance.xml/UseStringBufferLength"/>
 
+  <rule ref="category/java/codestyle.xml/FieldDeclarationsShouldBeAtStartOfClass">
+    <properties>
+      <property name="ignoreAnonymousClassDeclarations" value="false" />
+      <property name="ignoreEnumDeclarations" value="false" />
+    </properties>
+  </rule>
+
   <exclude-pattern>.*/generated-sources/.*</exclude-pattern>
 </ruleset>

hadoop-hdds/rocks-native/src/main/java/org/apache/hadoop/hdds/utils/NativeConstants.java

@@ -22,10 +22,10 @@
  */
 public final class NativeConstants {
 
+  public static final String ROCKS_TOOLS_NATIVE_LIBRARY_NAME = "ozone_rocksdb_tools";
+  public static final String ROCKS_TOOLS_NATIVE_PROPERTY = "rocks_tools_native";
+
   private NativeConstants() {
 
   }
-
-  public static final String ROCKS_TOOLS_NATIVE_LIBRARY_NAME = "ozone_rocksdb_tools";
-  public static final String ROCKS_TOOLS_NATIVE_PROPERTY = "rocks_tools_native";
 }

hadoop-hdds/rocksdb-checkpoint-differ/src/main/java/org/apache/ozone/compaction/log/CompactionLogEntry.java

@@ -39,10 +39,6 @@ public final class CompactionLogEntry implements
       CompactionLogEntry::getProtobuf,
       CompactionLogEntry.class);
 
-  public static Codec<CompactionLogEntry> getCodec() {
-    return CODEC;
-  }
-
   private final long dbSequenceNumber;
   private final long compactionTime;
   private final List<CompactionFileInfo> inputFileInfoList;
@@ -62,6 +58,10 @@ public CompactionLogEntry(long dbSequenceNumber,
     this.compactionReason = compactionReason;
   }
 
+  public static Codec<CompactionLogEntry> getCodec() {
+    return CODEC;
+  }
+
   public List<CompactionFileInfo> getInputFileInfoList() {
     return inputFileInfoList;
   }

hadoop-hdds/rocksdb-checkpoint-differ/src/main/java/org/apache/ozone/graph/PrintableGraph.java

@@ -38,26 +38,6 @@
  */
 public class PrintableGraph {
 
-  /**
-   * Enum to print different type of node's name in the graph image.
-   */
-  public enum GraphType {
-    /**
-     * To use SST file name as node name.
-     */
-    FILE_NAME,
-
-    /**
-     * To use SST file name and total key in the file as node name.
-     */
-    KEY_SIZE,
-
-    /**
-     * To use SST file name and cumulative key as node name.
-     */
-    CUMULATIVE_SIZE
-  }
-
   private final Graph<String, Edge> graph;
 
   public PrintableGraph(MutableGraph<CompactionNode> guavaGraph,
@@ -119,4 +99,24 @@ private String getVertex(CompactionNode node, GraphType graphType) {
       return node.getFileName();
     }
   }
+
+  /**
+   * Enum to print different type of node's name in the graph image.
+   */
+  public enum GraphType {
+    /**
+     * To use SST file name as node name.
+     */
+    FILE_NAME,
+
+    /**
+     * To use SST file name and total key in the file as node name.
+     */
+    KEY_SIZE,
+
+    /**
+     * To use SST file name and cumulative key as node name.
+     */
+    CUMULATIVE_SIZE
+  }
 }

hadoop-hdds/rocksdb-checkpoint-differ/src/main/java/org/apache/ozone/rocksdiff/RocksDBCheckpointDiffer.java

@@ -179,6 +179,35 @@ public class RocksDBCheckpointDiffer implements AutoCloseable,
   public static final Set<String> COLUMN_FAMILIES_TO_TRACK_IN_DAG =
       ImmutableSet.of("keyTable", "directoryTable", "fileTable");
 
+  // Hash table to track CompactionNode for a given SST File.
+  private final ConcurrentHashMap<String, CompactionNode> compactionNodeMap =
+      new ConcurrentHashMap<>();
+
+  // We are maintaining a two way DAG. This allows easy traversal from
+  // source snapshot to destination snapshot as well as the other direction.
+
+  private final MutableGraph<CompactionNode> forwardCompactionDAG =
+      GraphBuilder.directed().build();
+
+  private final MutableGraph<CompactionNode> backwardCompactionDAG =
+      GraphBuilder.directed().build();
+
+  public static final Integer DEBUG_DAG_BUILD_UP = 2;
+  public static final Integer DEBUG_DAG_TRAVERSAL = 3;
+  public static final Integer DEBUG_DAG_LIVE_NODES = 4;
+  public static final Integer DEBUG_READ_ALL_DB_KEYS = 5;
+  private static final HashSet<Integer> DEBUG_LEVEL = new HashSet<>();
+
+  static {
+    addDebugLevel(DEBUG_DAG_BUILD_UP);
+    addDebugLevel(DEBUG_DAG_TRAVERSAL);
+    addDebugLevel(DEBUG_DAG_LIVE_NODES);
+  }
+
+  static {
+    RocksDB.loadLibrary();
+  }
+
   /**
    * This is a package private constructor and should not be used other than
    * testing. Caller should use RocksDBCheckpointDifferHolder#getInstance() to
@@ -309,35 +338,6 @@ public void close() {
     }
   }
 
-  // Hash table to track CompactionNode for a given SST File.
-  private final ConcurrentHashMap<String, CompactionNode> compactionNodeMap =
-      new ConcurrentHashMap<>();
-
-  // We are maintaining a two way DAG. This allows easy traversal from
-  // source snapshot to destination snapshot as well as the other direction.
-
-  private final MutableGraph<CompactionNode> forwardCompactionDAG =
-      GraphBuilder.directed().build();
-
-  private final MutableGraph<CompactionNode> backwardCompactionDAG =
-      GraphBuilder.directed().build();
-
-  public static final Integer DEBUG_DAG_BUILD_UP = 2;
-  public static final Integer DEBUG_DAG_TRAVERSAL = 3;
-  public static final Integer DEBUG_DAG_LIVE_NODES = 4;
-  public static final Integer DEBUG_READ_ALL_DB_KEYS = 5;
-  private static final HashSet<Integer> DEBUG_LEVEL = new HashSet<>();
-
-  static {
-    addDebugLevel(DEBUG_DAG_BUILD_UP);
-    addDebugLevel(DEBUG_DAG_TRAVERSAL);
-    addDebugLevel(DEBUG_DAG_LIVE_NODES);
-  }
-
-  static {
-    RocksDB.loadLibrary();
-  }
-
   public static void addDebugLevel(Integer level) {
     DEBUG_LEVEL.add(level);
   }

hadoop-ozone/cli-shell/src/main/java/org/apache/hadoop/ozone/shell/ListOptions.java

@@ -26,19 +26,6 @@ public class ListOptions {
 
   @CommandLine.ArgGroup(exclusive = true)
   private ExclusiveLimit exclusiveLimit = new ExclusiveLimit();
-
-  static class ExclusiveLimit {
-    @CommandLine.Option(names = {"--length", "-l"},
-        description = "Maximum number of items to list",
-        defaultValue = "100",
-        showDefaultValue = CommandLine.Help.Visibility.ALWAYS)
-    private int limit;
-
-    @CommandLine.Option(names = {"--all", "-a"},
-        description = "List all results",
-        defaultValue = "false")
-    private boolean all;
-  }
 
   @CommandLine.Option(names = {"--start", "-s"},
       description = "The item to start the listing from.\n" +
@@ -72,4 +59,17 @@ public String getStartItem() {
   public String getPrefix() {
     return prefix;
   }
+
+  static class ExclusiveLimit {
+    @CommandLine.Option(names = {"--length", "-l"},
+        description = "Maximum number of items to list",
+        defaultValue = "100",
+        showDefaultValue = CommandLine.Help.Visibility.ALWAYS)
+    private int limit;
+
+    @CommandLine.Option(names = {"--all", "-a"},
+        description = "List all results",
+        defaultValue = "false")
+    private boolean all;
+  }
 }

hadoop-ozone/cli-shell/src/main/java/org/apache/hadoop/ozone/shell/bucket/CreateBucketHandler.java

@@ -57,28 +57,6 @@ public class CreateBucketHandler extends BucketHandler {
               " user if not specified")
   private String ownerName;
 
-  private static class LayoutConverter implements CommandLine.ITypeConverter<BucketLayout> {
-    @Override
-    public BucketLayout convert(String value) {
-      if (value == null) {
-        return null;
-      }
-      switch (value) {
-      case "fso":
-        return BucketLayout.FILE_SYSTEM_OPTIMIZED;
-      case "obs":
-        return BucketLayout.OBJECT_STORE;
-      default:
-        for (BucketLayout candidate : BucketLayout.values()) {
-          if (candidate.name().equalsIgnoreCase(value)) {
-            return candidate;
-          }
-        }
-        throw new IllegalArgumentException("Unknown bucket layout: " + value);
-      }
-    }
-  }
-
   @Option(names = { "--layout", "-l" }, converter = LayoutConverter.class,
           description = "Allowed Bucket Layouts: fso (for file system optimized buckets FILE_SYSTEM_OPTIMIZED), " +
                   "obs (for object store optimized OBJECT_STORE) and legacy (LEGACY is Deprecated)")
@@ -149,4 +127,26 @@ public void execute(OzoneClient client, OzoneAddress address)
       printObjectAsJson(bucket);
     }
   }
+
+  private static class LayoutConverter implements CommandLine.ITypeConverter<BucketLayout> {
+    @Override
+    public BucketLayout convert(String value) {
+      if (value == null) {
+        return null;
+      }
+      switch (value) {
+      case "fso":
+        return BucketLayout.FILE_SYSTEM_OPTIMIZED;
+      case "obs":
+        return BucketLayout.OBJECT_STORE;
+      default:
+        for (BucketLayout candidate : BucketLayout.values()) {
+          if (candidate.name().equalsIgnoreCase(value)) {
+            return candidate;
+          }
+        }
+        throw new IllegalArgumentException("Unknown bucket layout: " + value);
+      }
+    }
+  }
 }

hadoop-ozone/client/src/main/java/org/apache/hadoop/ozone/client/OzoneClientFactory.java

@@ -50,14 +50,13 @@ public final class OzoneClientFactory {
   private static final Logger LOG = LoggerFactory.getLogger(
       OzoneClientFactory.class);
 
+  private static final LeakDetector OZONE_CLIENT_LEAK_DETECTOR = new LeakDetector("OzoneClientObject");
+
   /**
    * Private constructor, class is not meant to be initialized.
    */
   private OzoneClientFactory() { }
 
-  private static final LeakDetector OZONE_CLIENT_LEAK_DETECTOR =
-      new LeakDetector("OzoneClientObject");
-
   public static UncheckedAutoCloseable track(AutoCloseable object) {
     final Class<?> clazz = object.getClass();
     final StackTraceElement[] stackTrace = HddsUtils.getStackTrace(LOG);

hadoop-ozone/client/src/main/java/org/apache/hadoop/ozone/client/checksum/ReplicatedBlockChecksumComputer.java

@@ -39,14 +39,14 @@ public class ReplicatedBlockChecksumComputer extends
   private static final Logger LOG =
       LoggerFactory.getLogger(ReplicatedBlockChecksumComputer.class);
 
+  private final List<ContainerProtos.ChunkInfo> chunkInfoList;
+
   static MD5Hash digest(ByteBuffer data) {
     final MessageDigest digester = MD5Hash.getDigester();
     digester.update(data);
     return new MD5Hash(digester.digest());
   }
 
-  private final List<ContainerProtos.ChunkInfo> chunkInfoList;
-
   public ReplicatedBlockChecksumComputer(
       List<ContainerProtos.ChunkInfo> chunkInfoList) {
     this.chunkInfoList = chunkInfoList;

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

@@ -55,6 +55,9 @@
  */
 public final class ECKeyOutputStream extends KeyOutputStream
     implements KeyMetadataAware {
+
+  private static final Logger LOG = LoggerFactory.getLogger(KeyOutputStream.class);
+
   private OzoneClientConfig config;
   private ECChunkBuffers ecChunkBufferCache;
   private final BlockingQueue<ECChunkBuffers> ecStripeQueue;
@@ -75,14 +78,6 @@ public final class ECKeyOutputStream extends KeyOutputStream
    */
   private boolean atomicKeyCreation;
 
-  private enum StripeWriteStatus {
-    SUCCESS,
-    FAILED
-  }
-
-  private static final Logger LOG =
-      LoggerFactory.getLogger(KeyOutputStream.class);
-
   private volatile boolean closed;
   private volatile boolean closing;
   // how much of data is actually written yet to underlying stream
@@ -730,4 +725,9 @@ private void releaseBuffers(ByteBuffer[] buffers) {
       }
     }
   }
+
+  private enum StripeWriteStatus {
+    SUCCESS,
+    FAILED
+  }
 }

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

@@ -58,18 +58,10 @@
 public class KeyDataStreamOutput extends AbstractDataStreamOutput
     implements KeyMetadataAware {
 
-  private OzoneClientConfig config;
-
-  /**
-   * Defines stream action while calling handleFlushOrClose.
-   */
-  enum StreamAction {
-    FLUSH, HSYNC, CLOSE, FULL
-  }
-
   private static final Logger LOG =
       LoggerFactory.getLogger(KeyDataStreamOutput.class);
 
+  private OzoneClientConfig config;
   private boolean closed;
 
   // how much of data is actually written yet to underlying stream
@@ -560,4 +552,11 @@ private void checkNotClosed() throws IOException {
               + blockDataStreamOutputEntryPool.getKeyName());
     }
   }
+
+  /**
+   * Defines stream action while calling handleFlushOrClose.
+   */
+  enum StreamAction {
+    FLUSH, HSYNC, CLOSE, FULL
+  }
 }