Cleanup: Remove unused private fields flagged by new UnusedPrivateFie…

hbase-backup/src/main/java/org/apache/hadoop/hbase/backup/impl/BackupSystemTable.java

@@ -167,7 +167,6 @@ public String toString() {
   private final Connection connection;
 
   private final static String BACKUP_INFO_PREFIX = "session:";
-  private final static String START_CODE_ROW = "startcode:";
   private final static byte[] ACTIVE_SESSION_ROW = Bytes.toBytes("activesession:");
   private final static byte[] ACTIVE_SESSION_COL = Bytes.toBytes("c");
 

hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapreduce/TestTableInputFormat.java

@@ -79,8 +79,6 @@ public class TestTableInputFormat {
   private static MiniMRCluster mrCluster;
   static final byte[] FAMILY = Bytes.toBytes("family");
 
-  private static final byte[][] columns = new byte[][] { FAMILY };
-
   @BeforeAll
   public static void beforeClass() throws Exception {
     UTIL.startMiniCluster();

hbase-server/src/main/java/org/apache/hadoop/hbase/quotas/MasterQuotasObserver.java

@@ -45,7 +45,6 @@ public class MasterQuotasObserver implements MasterCoprocessor, MasterObserver {
   public static final String REMOVE_QUOTA_ON_TABLE_DELETE = "hbase.quota.remove.on.table.delete";
   public static final boolean REMOVE_QUOTA_ON_TABLE_DELETE_DEFAULT = true;
 
-  private CoprocessorEnvironment cpEnv;
   private Configuration conf;
   private boolean quotasEnabled = false;
   private MasterServices masterServices;

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HMobStore.java

@@ -102,7 +102,6 @@ public class HMobStore extends HStore {
   // table, we need to find the original mob files by this table name. For details please see
   // cloning snapshot for mob files.
   private final byte[] refCellTags;
-  private StoreFileTracker mobStoreSFT = null;
 
   public HMobStore(final HRegion region, final ColumnFamilyDescriptor family,
     final Configuration confParam, boolean warmup) throws IOException {

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/metrics/MetricsThrottleExceptions.java

@@ -29,15 +29,6 @@ public class MetricsThrottleExceptions {
    */
   private static final String METRICS_NAME = "ThrottleExceptions";
 
-  /**
-   * The name of the metrics context that metrics will be under.
-   */
-  private static final String METRICS_CONTEXT = "regionserver";
-
-  /**
-   * Description
-   */
-  private static final String METRICS_DESCRIPTION = "Metrics about RPC throttling exceptions";
 
   /**
    * The name of the metrics context that metrics will be under in jmx

hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestCompactionArchiveConcurrentClose.java

@@ -64,7 +64,6 @@ public class TestCompactionArchiveConcurrentClose {
   private HBaseTestingUtil testUtil;
 
   private Path testDir;
-  private AtomicBoolean archived = new AtomicBoolean();
 
   // Static field to track archived state for the static inner class
   private static final AtomicBoolean STATIC_ARCHIVED = new AtomicBoolean();

hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestMetricsUserAggregate.java

@@ -47,7 +47,6 @@ public class TestMetricsUserAggregate {
   private MetricsRegionServerWrapperStub wrapper;
   private MetricsRegionServer rsm;
   private MetricsUserAggregate userAgg;
-  private TableName tableName = TableName.valueOf("testUserAggregateMetrics");
 
   @BeforeAll
   public static void classSetUp() {

hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStoreScanner.java

@@ -98,7 +98,6 @@ public void setTestName(TestInfo testInfo) {
   private static final String CF_STR = "cf";
   private static final byte[] CF = Bytes.toBytes(CF_STR);
   static Configuration CONF = HBaseConfiguration.create();
-  private static final HBaseTestingUtil TEST_UTIL = new HBaseTestingUtil();
   private ScanInfo scanInfo = new ScanInfo(CONF, CF, 0, Integer.MAX_VALUE, Long.MAX_VALUE,
     KeepDeletedCells.FALSE, HConstants.DEFAULT_BLOCKSIZE, 0, CellComparator.getInstance(), false);