Mark member variables as final in server-base (#4833)

See #4830

server/base/src/main/java/org/apache/accumulo/server/compaction/ProvisionalCompactionPlanner.java

@@ -33,7 +33,7 @@
 public class ProvisionalCompactionPlanner implements CompactionPlanner {
 
   private final CompactionServiceId serviceId;
-  private AtomicLong lastWarnNanoTime = new AtomicLong(System.nanoTime());
+  private final AtomicLong lastWarnNanoTime = new AtomicLong(System.nanoTime());
 
   public ProvisionalCompactionPlanner(CompactionServiceId serviceId) {
     this.serviceId = serviceId;

server/base/src/main/java/org/apache/accumulo/server/data/ServerColumnUpdate.java

@@ -22,7 +22,7 @@
 
 public class ServerColumnUpdate extends ColumnUpdate {
 
-  ServerMutation parent;
+  final ServerMutation parent;
 
   public ServerColumnUpdate(byte[] cf, byte[] cq, byte[] cv, boolean hasts, long ts,
       boolean deleted, byte[] val, ServerMutation serverMutation) {

server/base/src/main/java/org/apache/accumulo/server/data/ServerConditionalMutation.java

@@ -25,8 +25,8 @@
 
 public class ServerConditionalMutation extends ServerMutation {
 
-  private long cmid;
-  private List<TCondition> conditions;
+  private final long cmid;
+  private final List<TCondition> conditions;
 
   public ServerConditionalMutation(TConditionalMutation input) {
     super(input.mutation);

server/base/src/main/java/org/apache/accumulo/server/fs/FileManager.java

@@ -68,9 +68,9 @@ public class FileManager {
   private int maxOpen;
 
   private static class OpenReader implements Comparable<OpenReader> {
-    long releaseTime;
-    FileSKVIterator reader;
-    StoredTabletFile file;
+    final long releaseTime;
+    final FileSKVIterator reader;
+    final StoredTabletFile file;
 
     public OpenReader(StoredTabletFile file, FileSKVIterator reader) {
       this.file = file;
@@ -383,7 +383,7 @@ private void releaseReaders(KeyExtent tablet, List<FileSKVIterator> readers,
   static class FileDataSource implements DataSource {
 
     private SortedKeyValueIterator<Key,Value> iter;
-    private ArrayList<FileDataSource> deepCopies;
+    private final ArrayList<FileDataSource> deepCopies;
     private boolean current = true;
     private IteratorEnvironment env;
     private StoredTabletFile file;
@@ -456,11 +456,11 @@ public void setInterruptFlag(AtomicBoolean flag) {
 
   public class ScanFileManager {
 
-    private ArrayList<FileDataSource> dataSources;
-    private ArrayList<FileSKVIterator> tabletReservedReaders;
-    private KeyExtent tablet;
+    private final ArrayList<FileDataSource> dataSources;
+    private final ArrayList<FileSKVIterator> tabletReservedReaders;
+    private final KeyExtent tablet;
     private boolean continueOnFailure;
-    private CacheProvider cacheProvider;
+    private final CacheProvider cacheProvider;
 
     ScanFileManager(KeyExtent tablet, CacheProvider cacheProvider) {
       tabletReservedReaders = new ArrayList<>();

server/base/src/main/java/org/apache/accumulo/server/fs/VolumeManager.java

@@ -53,7 +53,7 @@ public interface VolumeManager extends AutoCloseable {
   enum FileType {
     TABLE(Constants.TABLE_DIR), WAL(Constants.WAL_DIR), RECOVERY(Constants.RECOVERY_DIR);
 
-    private String dir;
+    private final String dir;
 
     FileType(String dir) {
       this.dir = dir;

server/base/src/main/java/org/apache/accumulo/server/fs/VolumeUtil.java

@@ -88,8 +88,8 @@ public static LogEntry switchVolume(LogEntry le, Map<Path,Path> replacements) {
 
   public static class TabletFiles {
     public String dirName;
-    public List<LogEntry> logEntries;
-    public SortedMap<StoredTabletFile,DataFileValue> datafiles;
+    public final List<LogEntry> logEntries;
+    public final SortedMap<StoredTabletFile,DataFileValue> datafiles;
 
     public TabletFiles() {
       logEntries = new ArrayList<>();

server/base/src/main/java/org/apache/accumulo/server/init/FileSystemInitializer.java

@@ -73,10 +73,12 @@ public FileSystemInitializer(InitialConfiguration initConfig) {
   }
 
   public static class InitialTablet {
-    TableId tableId;
-    String dirName;
-    Text prevEndRow, endRow, extent;
-    String[] files;
+    final TableId tableId;
+    final String dirName;
+    final Text prevEndRow;
+    final Text endRow;
+    final Text extent;
+    final String[] files;
 
     InitialTablet(TableId tableId, String dirName, Text prevEndRow, Text endRow, String... files) {
       this.tableId = tableId;

server/base/src/main/java/org/apache/accumulo/server/log/SortedLogState.java

@@ -28,7 +28,7 @@
 public enum SortedLogState {
   FINISHED("finished"), FAILED("failed");
 
-  private String marker;
+  private final String marker;
 
   private SortedLogState(String marker) {
     this.marker = marker;

server/base/src/main/java/org/apache/accumulo/server/manager/LiveTServerSet.java

@@ -184,9 +184,9 @@ public void flush(ServiceLock lock, TableId tableId, byte[] startRow, byte[] end
   }
 
   static class TServerInfo {
-    TServerConnection connection;
-    TServerInstance instance;
-    String resourceGroup;
+    final TServerConnection connection;
+    final TServerInstance instance;
+    final String resourceGroup;
 
     TServerInfo(TServerInstance instance, TServerConnection connection, String resourceGroup) {
       this.connection = connection;

server/base/src/main/java/org/apache/accumulo/server/manager/state/LoggingTabletStateStore.java

@@ -40,7 +40,7 @@
  */
 class LoggingTabletStateStore implements TabletStateStore {
 
-  private TabletStateStore wrapped;
+  private final TabletStateStore wrapped;
 
   LoggingTabletStateStore(TabletStateStore tss) {
     this.wrapped = tss;

server/base/src/main/java/org/apache/accumulo/server/manager/state/TabletServerState.java

@@ -43,8 +43,8 @@ public enum TabletServerState {
 
   private byte id;
 
-  private static HashMap<Byte,TabletServerState> mapping;
-  private static HashSet<TabletServerState> badStates;
+  private static final HashMap<Byte,TabletServerState> mapping;
+  private static final HashSet<TabletServerState> badStates;
 
   static {
     mapping = new HashMap<>(TabletServerState.values().length);

server/base/src/main/java/org/apache/accumulo/server/metadata/ConditionalTabletsMutatorImpl.java

@@ -59,13 +59,13 @@ public class ConditionalTabletsMutatorImpl implements Ample.ConditionalTabletsMu
   private final ServerContext context;
   private Ample.DataLevel dataLevel = null;
 
-  private List<ConditionalMutation> mutations = new ArrayList<>();
+  private final List<ConditionalMutation> mutations = new ArrayList<>();
 
-  private Map<Text,KeyExtent> extents = new HashMap<>();
+  private final Map<Text,KeyExtent> extents = new HashMap<>();
 
   private boolean active = true;
 
-  Map<KeyExtent,Ample.RejectionHandler> rejectedHandlers = new HashMap<>();
+  final Map<KeyExtent,Ample.RejectionHandler> rejectedHandlers = new HashMap<>();
   private final Function<DataLevel,String> tableMapper;
 
   public ConditionalTabletsMutatorImpl(ServerContext context) {

server/base/src/main/java/org/apache/accumulo/server/metadata/ScanServerRefStoreImpl.java

@@ -40,7 +40,7 @@
 
 public class ScanServerRefStoreImpl implements ScanServerRefStore {
 
-  private static Logger log = LoggerFactory.getLogger(ScanServerRefStoreImpl.class);
+  private static final Logger log = LoggerFactory.getLogger(ScanServerRefStoreImpl.class);
 
   private final ClientContext context;
   private final String tableName;

server/base/src/main/java/org/apache/accumulo/server/metadata/ServerAmpleImpl.java

@@ -62,7 +62,7 @@
 
 public class ServerAmpleImpl extends AmpleImpl implements Ample {
 
-  private static Logger log = LoggerFactory.getLogger(ServerAmpleImpl.class);
+  private static final Logger log = LoggerFactory.getLogger(ServerAmpleImpl.class);
 
   private final ServerContext context;
   private final ScanServerRefStore scanServerRefStore;

server/base/src/main/java/org/apache/accumulo/server/problems/ProblemReport.java

@@ -44,9 +44,9 @@
 import org.apache.zookeeper.KeeperException;
 
 public class ProblemReport {
-  private TableId tableId;
-  private ProblemType problemType;
-  private String resource;
+  private final TableId tableId;
+  private final ProblemType problemType;
+  private final String resource;
   private String exception;
   private String server;
   private long creationTime;

server/base/src/main/java/org/apache/accumulo/server/problems/ProblemReportingIterator.java

@@ -37,8 +37,8 @@ public class ProblemReportingIterator implements InterruptibleIterator {
   private final SortedKeyValueIterator<Key,Value> source;
   private boolean sawError = false;
   private final boolean continueOnError;
-  private String resource;
-  private TableId tableId;
+  private final String resource;
+  private final TableId tableId;
   private final ServerContext context;
 
   public ProblemReportingIterator(ServerContext context, TableId tableId, String resource,

server/base/src/main/java/org/apache/accumulo/server/problems/ProblemReports.java

@@ -192,7 +192,7 @@ private static boolean isMeta(TableId tableId) {
   public Iterator<ProblemReport> iterator(final TableId table) {
     return new Iterator<>() {
 
-      ZooReaderWriter zoo = context.getZooReaderWriter();
+      final ZooReaderWriter zoo = context.getZooReaderWriter();
       private int iter1Count = 0;
       private Iterator<String> iter1;
 

server/base/src/main/java/org/apache/accumulo/server/security/delegation/AuthenticationTokenKeyManager.java

@@ -36,8 +36,8 @@ public class AuthenticationTokenKeyManager implements Runnable {
   private final ZooAuthenticationKeyDistributor keyDistributor;
 
   private long lastKeyUpdate = 0;
-  private long keyUpdateInterval;
-  private long tokenMaxLifetime;
+  private final long keyUpdateInterval;
+  private final long tokenMaxLifetime;
   private int idSeq = 0;
   private volatile boolean keepRunning = true, initialized = false;
 

server/base/src/main/java/org/apache/accumulo/server/security/delegation/ZooAuthenticationKeyDistributor.java

@@ -49,7 +49,7 @@ public class ZooAuthenticationKeyDistributor {
 
   private final ZooReaderWriter zk;
   private final String baseNode;
-  private AtomicBoolean initialized = new AtomicBoolean(false);
+  private final AtomicBoolean initialized = new AtomicBoolean(false);
 
   public ZooAuthenticationKeyDistributor(ZooReaderWriter zk, String baseNode) {
     requireNonNull(zk);

server/base/src/main/java/org/apache/accumulo/server/tablets/ConditionCheckerContext.java

@@ -51,24 +51,24 @@
 import org.apache.hadoop.io.Text;
 
 public class ConditionCheckerContext {
-  private CompressedIterators compressedIters;
+  private final CompressedIterators compressedIters;
 
-  private List<IterInfo> tableIters;
-  private Map<String,Map<String,String>> tableIterOpts;
-  private TabletIteratorEnvironment tie;
-  private String context;
+  private final List<IterInfo> tableIters;
+  private final Map<String,Map<String,String>> tableIterOpts;
+  private final TabletIteratorEnvironment tie;
+  private final String context;
 
   private static class MergedIterConfig {
-    List<IterInfo> mergedIters;
-    Map<String,Map<String,String>> mergedItersOpts;
+    final List<IterInfo> mergedIters;
+    final Map<String,Map<String,String>> mergedItersOpts;
 
     MergedIterConfig(List<IterInfo> mergedIters, Map<String,Map<String,String>> mergedItersOpts) {
       this.mergedIters = mergedIters;
       this.mergedItersOpts = mergedItersOpts;
     }
   }
 
-  private Map<ByteSequence,MergedIterConfig> mergedIterCache = new HashMap<>();
+  private final Map<ByteSequence,MergedIterConfig> mergedIterCache = new HashMap<>();
 
   public ConditionCheckerContext(ServerContext context, CompressedIterators compressedIters,
       TableConfiguration tableConf) {
@@ -144,9 +144,9 @@ boolean checkConditions(SortedKeyValueIterator<Key,Value> systemIter,
 
   public class ConditionChecker {
 
-    private List<ServerConditionalMutation> conditionsToCheck;
-    private List<ServerConditionalMutation> okMutations;
-    private List<TCMResult> results;
+    private final List<ServerConditionalMutation> conditionsToCheck;
+    private final List<ServerConditionalMutation> okMutations;
+    private final List<TCMResult> results;
     private boolean checked = false;
 
     public ConditionChecker(List<ServerConditionalMutation> conditionsToCheck,

server/base/src/main/java/org/apache/accumulo/server/tablets/TabletTime.java

@@ -148,7 +148,7 @@ public long getAndUpdateTime() {
   }
 
   static class LogicalTime extends TabletTime {
-    AtomicLong nextTime;
+    final AtomicLong nextTime;
 
     private LogicalTime(Long time) {
       this.nextTime = new AtomicLong(time + 1);

server/base/src/main/java/org/apache/accumulo/server/util/RandomWriter.java

@@ -42,12 +42,12 @@
 
 public class RandomWriter {
 
-  private static int num_columns_per_row = 1;
-  private static int num_payload_bytes = 1024;
+  private static final int num_columns_per_row = 1;
+  private static final int num_payload_bytes = 1024;
   private static final Logger log = LoggerFactory.getLogger(RandomWriter.class);
 
   public static class RandomMutationGenerator implements Iterable<Mutation>, Iterator<Mutation> {
-    private long max_mutations;
+    private final long max_mutations;
     private int mutations_so_far = 0;
     private static final Logger log = LoggerFactory.getLogger(RandomMutationGenerator.class);
 
@@ -93,7 +93,7 @@ static class Opts extends ClientOpts {
     @Parameter(names = "--count", description = "number of mutations to write", required = true)
     long count;
     @Parameter(names = "--table", description = "table to use")
-    String tableName = "test_write_table";
+    final String tableName = "test_write_table";
   }
 
   public static void main(String[] args) throws Exception {

server/base/src/main/java/org/apache/accumulo/server/util/TableDiskUsage.java

@@ -79,10 +79,10 @@ public class TableDiskUsage {
 
   private static final Logger log = LoggerFactory.getLogger(TableDiskUsage.class);
   private int nextInternalId = 0;
-  private Map<TableId,Integer> internalIds = new HashMap<>();
-  private Map<Integer,TableId> externalIds = new HashMap<>();
-  private Map<String,Integer[]> tableFiles = new HashMap<>();
-  private Map<String,Long> fileSizes = new HashMap<>();
+  private final Map<TableId,Integer> internalIds = new HashMap<>();
+  private final Map<Integer,TableId> externalIds = new HashMap<>();
+  private final Map<String,Integer[]> tableFiles = new HashMap<>();
+  private final Map<String,Long> fileSizes = new HashMap<>();
 
   void addTable(TableId tableId) {
     if (internalIds.containsKey(tableId)) {
@@ -329,7 +329,7 @@ public static void printDiskUsage(Collection<String> tableNames, AccumuloClient
 
   static class Opts extends ServerUtilOpts {
     @Parameter(description = " <table> { <table> ... } ")
-    List<String> tables = new ArrayList<>();
+    final List<String> tables = new ArrayList<>();
   }
 
   public static void main(String[] args) throws Exception {

server/base/src/main/java/org/apache/accumulo/server/util/time/BaseRelativeTime.java

@@ -28,7 +28,7 @@ public class BaseRelativeTime implements ProvidesTime {
 
   private long diff = 0;
   private long lastReportedTime = 0;
-  ProvidesTime local;
+  final ProvidesTime local;
 
   BaseRelativeTime(ProvidesTime real, long lastReportedTime) {
     this.local = real;

server/base/src/main/java/org/apache/accumulo/server/util/time/RelativeTime.java

@@ -29,7 +29,7 @@ private RelativeTime() {
     super(new SystemTime());
   }
 
-  private static BaseRelativeTime instance = new RelativeTime();
+  private static final BaseRelativeTime instance = new RelativeTime();
 
   public static BaseRelativeTime getInstance() {
     return instance;

server/base/src/main/java/org/apache/accumulo/server/zookeeper/DistributedWorkQueue.java

@@ -58,12 +58,13 @@ public class DistributedWorkQueue {
 
   private static final Logger log = LoggerFactory.getLogger(DistributedWorkQueue.class);
 
-  private ZooReaderWriter zoo;
-  private String path;
-  private ServerContext context;
-  private long timerInitialDelay, timerPeriod;
+  private final ZooReaderWriter zoo;
+  private final String path;
+  private final ServerContext context;
+  private final long timerInitialDelay;
+  private final long timerPeriod;
 
-  private AtomicInteger numTask = new AtomicInteger(0);
+  private final AtomicInteger numTask = new AtomicInteger(0);
 
   /**
    * Finds a child in {@code children} that is not currently being processed and adds a Runnable to