Code cleanup

modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/RootQuery.java

@@ -276,7 +276,7 @@ public void run(ExecutionContext<RowT> ctx, ExecutionPlan plan, FieldsMetadata m
                 }
 
                 if (wrpEx != null)
-                    log.warning("An exception occures during the query cancel", wrpEx);
+                    log.warning("An exception occurs during the query cancel", wrpEx);
             }
             finally {
                 super.tryClose(failure == null && root != null ? root.failure() : failure);

modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/prepare/PlannerHelper.java

@@ -254,7 +254,7 @@ private static class FixDependentModifyNodeShuttle extends IgniteRelShuttle {
         /**
          * Process a scan node and raise a {@link #spoolNeeded flag} if needed.
          *
-         * @param scan TableScan to analize.
+         * @param scan TableScan to analyze.
          * @return The input rel.
          */
         private IgniteRel processScan(TableScan scan) {

modules/control-utility/src/test/java/org/apache/ignite/internal/commandline/CommandHandlerParsingTest.java

@@ -419,7 +419,7 @@ public void testParseAndValidateWalActions() {
     }
 
     /**
-     * Tets checks a parser of shutdown policy command.
+     * Tests checks a parser of shutdown policy command.
      */
     @Test
     public void testParseShutdownPolicyParameters() {

modules/core/src/main/java/org/apache/ignite/internal/cluster/IgniteClusterImpl.java

@@ -49,7 +49,6 @@
 import org.apache.ignite.cluster.ClusterNode;
 import org.apache.ignite.cluster.ClusterStartNodeResult;
 import org.apache.ignite.cluster.ClusterState;
-import org.apache.ignite.configuration.IgniteConfiguration;
 import org.apache.ignite.internal.GridKernalContext;
 import org.apache.ignite.internal.IgniteComponentType;
 import org.apache.ignite.internal.IgniteInternalFuture;
@@ -90,13 +89,10 @@
 /**
  *
  */
-public class IgniteClusterImpl extends ClusterGroupAdapter implements IgniteClusterEx, Externalizable {
+public class IgniteClusterImpl extends ClusterGroupAdapter implements IgniteClusterEx {
     /** */
     private static final long serialVersionUID = 0L;
 
-    /** */
-    private IgniteConfiguration cfg;
-
     /** Node local store. */
     @GridToStringExclude
     private ConcurrentMap nodeLoc;
@@ -141,8 +137,6 @@ public IgniteClusterImpl() {
     public IgniteClusterImpl(GridKernalContext ctx) {
         super(ctx, (IgnitePredicate<ClusterNode>)null);
 
-        cfg = ctx.config();
-
         nodeLoc = new ClusterNodeLocalMapImpl(ctx);
 
         log = ctx.log(getClass());

modules/core/src/main/java/org/apache/ignite/internal/management/cache/VerifyBackupPartitionsTaskV2.java

@@ -63,6 +63,7 @@
 import org.apache.ignite.resources.LoggerResource;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
+
 import static java.util.Collections.emptyMap;
 import static org.apache.ignite.internal.pagemem.PageIdAllocator.FLAG_DATA;
 import static org.apache.ignite.internal.processors.cache.verify.IdleVerifyUtility.GRID_NOT_IDLE_MSG;

modules/core/src/main/java/org/apache/ignite/internal/managers/communication/GridIoManager.java

@@ -2775,7 +2775,7 @@ public int getOutboundMessagesQueueSize() {
      * @param rctx Receiver context to use.
      * @param ex Exception to close receiver with.
      */
-    private void interruptReceiver(ReceiverContext rctx, Exception ex) {
+    private void interruptReceiver(@Nullable ReceiverContext rctx, Exception ex) {
         if (rctx == null)
             return;
 

modules/core/src/main/java/org/apache/ignite/internal/processors/cache/persistence/snapshot/IgniteSnapshotManager.java

@@ -2591,7 +2591,8 @@ public StandaloneGridKernalContext createStandaloneKernalContext(
      * @return Iterator over partition.
      * @throws IgniteCheckedException If and error occurs.
      */
-    public GridCloseableIterator<CacheDataRow> partitionRowIterator(GridKernalContext ctx,
+    public GridCloseableIterator<CacheDataRow> partitionRowIterator(
+        GridKernalContext ctx,
         String grpName,
         int partId,
         FilePageStore pageStore

modules/core/src/main/java/org/apache/ignite/internal/processors/cache/persistence/snapshot/SnapshotFilesRequestMessage.java

@@ -66,24 +66,24 @@ public SnapshotFilesRequestMessage() {
     }
 
     /**
-     * @param reqId Unique message id.
-     * @param requestId Snapshot operation request ID.
+     * @param msgId Unique message id.
+     * @param reqId Snapshot operation request ID.
      * @param snpName Snapshot name to request.
      * @param snpPath Snapshot directory path.
      * @param parts Map of cache group ids and corresponding set of its partition ids to be snapshot.
      */
     public SnapshotFilesRequestMessage(
-        String reqId,
-        UUID requestId,
+        String msgId,
+        UUID reqId,
         String snpName,
         @Nullable String snpPath,
         Map<Integer, Set<Integer>> parts
     ) {
-        super(reqId);
+        super(msgId);
 
         assert parts != null && !parts.isEmpty();
 
-        this.reqId = requestId;
+        this.reqId = reqId;
         this.snpName = snpName;
         this.snpPath = snpPath;
         this.parts = new HashMap<>();

modules/core/src/main/java/org/apache/ignite/internal/processors/cache/persistence/snapshot/dump/Dump.java

@@ -199,7 +199,7 @@ public List<String> nodesDirectories() {
     }
 
     /** @return List of snapshot metadata saved in {@link #dumpDir}. */
-    public List<SnapshotMetadata> metadata() throws IOException, IgniteCheckedException {
+    public List<SnapshotMetadata> metadata() {
         return Collections.unmodifiableList(metadata);
     }
 

modules/core/src/main/java/org/apache/ignite/internal/processors/datastructures/DataStructuresProcessor.java

@@ -349,9 +349,10 @@ private void startQuery(GridCacheContext cctx) throws IgniteCheckedException {
 
     /** {@inheritDoc} */
     @Override public void onActivate(GridKernalContext ctx) {
-        if (log.isDebugEnabled())
+        if (log.isDebugEnabled()) {
             log.debug("Activating data structure processor [nodeId=" + ctx.localNodeId() +
                 " topVer=" + ctx.discovery().topologyVersionEx() + " ]");
+        }
 
         initFailed = false;
 
@@ -466,9 +467,10 @@ public void restoreStructuresState(GridKernalContext ctx) {
 
     /** {@inheritDoc} */
     @Override public void onDeActivate(GridKernalContext ctx) {
-        if (log.isDebugEnabled())
+        if (log.isDebugEnabled()) {
             log.debug("DeActivate data structure processor [nodeId=" + ctx.localNodeId() +
                 ", topVer=" + ctx.discovery().topologyVersionEx() + "]");
+        }
 
         ctx.event().removeLocalEventListener(lsnr, EVT_NODE_LEFT, EVT_NODE_FAILED);
 

modules/core/src/main/java/org/apache/ignite/internal/processors/query/stat/IgniteStatisticsConfigurationManager.java

@@ -126,7 +126,7 @@ public class IgniteStatisticsConfigurationManager {
                 distrMetaStorage.listen(
                     (metaKey) -> metaKey.startsWith(STAT_OBJ_PREFIX),
                     (k, oldV, newV) -> {
-                        // Skip invoke on start node (see 'ReadableDistributedMetaStorage#listen' the second case)
+                        // Skip invocation at node start (see 'ReadableDistributedMetaStorage#listen' the second case)
                         // The update statistics on start node is handled by 'scanAndCheckLocalStatistic' method
                         // called on exchange done.
                         if (topVer == null)

modules/core/src/main/java/org/apache/ignite/internal/processors/query/stat/IgniteStatisticsHelper.java

@@ -220,13 +220,13 @@ public static ObjectStatisticsImpl aggregateLocalStatistics(
 
     /**
      * Calculate effective row count. If there are some overrides in statistics configuration - maximum value will be
-     * choosen. If not - will return actualRowCount.
+     * choosen. If not - will return {@code actualRowCnt}.
      *
      * @param cfg Statistics configuration to dig overrides row count from.
-     * @param actualRowCount Actual row count.
+     * @param actualRowCnt Actual row count.
      * @return Effective row count.
      */
-    public static long calculateRowCount(StatisticsObjectConfiguration cfg, long actualRowCount) {
+    public static long calculateRowCount(StatisticsObjectConfiguration cfg, long actualRowCnt) {
         long overridedRowCnt = -1;
 
         for (StatisticsColumnConfiguration ccfg : cfg.columns().values()) {
@@ -237,7 +237,7 @@ public static long calculateRowCount(StatisticsObjectConfiguration cfg, long act
             }
         }
 
-        return (overridedRowCnt == -1) ? actualRowCount : overridedRowCnt;
+        return (overridedRowCnt == -1) ? actualRowCnt : overridedRowCnt;
     }
 
     /**
@@ -247,7 +247,7 @@ public static long calculateRowCount(StatisticsObjectConfiguration cfg, long act
      * @return StatisticsObjectConfiguration array.
      */
     public static StatisticsObjectConfiguration[] buildDefaultConfigurations(StatisticsTarget... targets) {
-        StatisticsObjectConfiguration[] res = Arrays.stream(targets)
+        return Arrays.stream(targets)
             .map(t -> {
                 List<StatisticsColumnConfiguration> colCfgs;
                 if (t.columns() == null)
@@ -259,8 +259,6 @@ public static StatisticsObjectConfiguration[] buildDefaultConfigurations(Statist
                 return new StatisticsObjectConfiguration(t.key(), colCfgs,
                     StatisticsObjectConfiguration.DEFAULT_OBSOLESCENCE_MAX_PERCENT);
             }).toArray(StatisticsObjectConfiguration[]::new);
-
-        return res;
     }
 
     /**

modules/core/src/main/java/org/apache/ignite/internal/processors/query/stat/IgniteStatisticsManagerImpl.java

@@ -373,7 +373,7 @@ public ObjectStatisticsImpl getLocalStatistics(StatisticsKey key, AffinityTopolo
     }
 
     /** {@inheritDoc} */
-    @Override public void refreshStatistics(StatisticsTarget... targets) throws IgniteCheckedException {
+    @Override public void refreshStatistics(StatisticsTarget... targets) {
         ensureActive("refresh statistics");
 
         if (usageState() == OFF)
@@ -383,7 +383,7 @@ public ObjectStatisticsImpl getLocalStatistics(StatisticsKey key, AffinityTopolo
     }
 
     /** {@inheritDoc} */
-    @Override public void dropAll() throws IgniteCheckedException {
+    @Override public void dropAll() {
         ensureActive("drop all statistics");
 
         statCfgMgr.dropAll();
@@ -421,7 +421,7 @@ public IgniteStatisticsConfigurationManager statisticConfiguration() {
     }
 
     /** {@inheritDoc} */
-    @Override public void usageState(StatisticsUsageState state) throws IgniteCheckedException {
+    @Override public void usageState(StatisticsUsageState state) {
         ensureActive("change usage state of statistics");
 
         try {
@@ -486,8 +486,8 @@ public synchronized void processObsolescence() {
             try {
                 cfg = statCfgMgr.config(key);
             }
-            catch (IgniteCheckedException e) {
-                // No-op/
+            catch (IgniteCheckedException ignored) {
+                // No-op.
             }
 
             Set<Integer> tasksParts = calculateObsolescencedPartitions(cfg, statsRepos.getObsolescence(key));

modules/core/src/main/java/org/apache/ignite/internal/processors/query/stat/StatisticsUsageState.java

@@ -31,7 +31,7 @@ public enum StatisticsUsageState {
     NO_UPDATE(1),
 
     /**
-     * Statistics used and updated after each changes.
+     * Statistics used and updated after each change.
      */
     ON(2);
 
@@ -42,7 +42,7 @@ public enum StatisticsUsageState {
     private static final StatisticsUsageState[] VALS;
 
     static {
-        StatisticsUsageState[] statisticsUsageStates = StatisticsUsageState.values();
+        StatisticsUsageState[] statisticsUsageStates = values();
 
         int maxIdx = 0;
         for (StatisticsUsageState recordType : statisticsUsageStates)

modules/core/src/main/java/org/apache/ignite/internal/processors/query/stat/task/GatherPartitionStatistics.java

@@ -154,8 +154,7 @@ public LocalStatisticsGatheringContext context() {
     private ObjectPartitionStatisticsImpl processPartition(
         GridCacheContext<?, ?> cctx
     ) {
-        ObjectPartitionStatisticsImpl partStat = statRepo.getLocalPartitionStatistics(
-            gathCtx.configuration().key(), partId);
+        ObjectPartitionStatisticsImpl partStat = statRepo.getLocalPartitionStatistics(gathCtx.configuration().key(), partId);
 
         Map<String, StatisticsColumnConfiguration> colsToCollect = getColumnsToCollect(partStat);
         Set<String> colsToRemove = getColumnsToRemove(partStat);

modules/core/src/main/java/org/apache/ignite/internal/processors/task/GridTaskProcessor.java

@@ -211,8 +211,7 @@ public GridTaskProcessor(GridKernalContext ctx) {
         if (!active)
             return;
 
-        tasksMetaCache = ctx.security().enabled() ?
-            ctx.cache().<GridTaskNameHashKey, String>utilityCache() : null;
+        tasksMetaCache = ctx.security().enabled() ? ctx.cache().utilityCache() : null;
 
         startLatch.countDown();
     }

modules/core/src/main/java/org/apache/ignite/internal/util/distributed/InitMessage.java

@@ -44,7 +44,7 @@ public class InitMessage<I extends Serializable> implements DiscoveryCustomMessa
     private final IgniteUuid id = IgniteUuid.randomUuid();
 
     /** Process id. */
-    private final UUID processId;
+    private final UUID procId;
 
     /** Process type. */
     private final int type;
@@ -56,12 +56,12 @@ public class InitMessage<I extends Serializable> implements DiscoveryCustomMessa
     private final boolean waitClnRes;
 
     /**
-     * @param processId Process id.
+     * @param procId Process id.
      * @param type Process type.
      * @param req Request.
      */
-    public InitMessage(UUID processId, DistributedProcessType type, I req, boolean waitClnRes) {
-        this.processId = processId;
+    public InitMessage(UUID procId, DistributedProcessType type, I req, boolean waitClnRes) {
+        this.procId = procId;
         this.type = type.ordinal();
         this.req = req;
         this.waitClnRes = waitClnRes;
@@ -90,7 +90,7 @@ public InitMessage(UUID processId, DistributedProcessType type, I req, boolean w
 
     /** @return Process id. */
     public UUID processId() {
-        return processId;
+        return procId;
     }
 
     /** @return Process type. */

modules/core/src/main/java/org/apache/ignite/spi/IgniteSpiOperationTimeoutHelper.java

@@ -111,7 +111,7 @@ public long nextTimeoutChunk(long dfltTimeout) throws IgniteSpiOperationTimeoutE
      * @param e Exception to check.
      * @return {@code True} if given exception is a timeout. {@code False} otherwise.
      */
-    public boolean checkFailureTimeoutReached(Exception e) {
+    public static boolean checkFailureTimeoutReached(Exception e) {
         return X.hasCause(e, IgniteSpiOperationTimeoutException.class, SocketTimeoutException.class, SocketException.class);
     }
 }

modules/core/src/main/java/org/apache/ignite/spi/discovery/tcp/ClientImpl.java

@@ -200,7 +200,7 @@ class ClientImpl extends TcpDiscoveryImpl {
     private final CountDownLatch leaveLatch = new CountDownLatch(1);
 
     /** */
-    private final ScheduledExecutorService executorService;
+    private final ScheduledExecutorService executorSrvc;
 
     /** */
     private MessageWorker msgWorker;
@@ -221,7 +221,7 @@ class ClientImpl extends TcpDiscoveryImpl {
         String instanceName = adapter.ignite() == null || adapter.ignite().name() == null
             ? "client-node" : adapter.ignite().name();
 
-        executorService = Executors.newSingleThreadScheduledExecutor(
+        executorSrvc = Executors.newSingleThreadScheduledExecutor(
             new IgniteThreadFactory(instanceName, "tcp-discovery-exec"));
     }
 
@@ -318,7 +318,7 @@ class ClientImpl extends TcpDiscoveryImpl {
             }
         }.start();
 
-        executorService.scheduleAtFixedRate(new MetricsSender(), spi.metricsUpdateFreq, spi.metricsUpdateFreq, MILLISECONDS);
+        executorSrvc.scheduleAtFixedRate(new MetricsSender(), spi.metricsUpdateFreq, spi.metricsUpdateFreq, MILLISECONDS);
 
         try {
             joinLatch.await();
@@ -369,7 +369,7 @@ class ClientImpl extends TcpDiscoveryImpl {
         while (!U.join(sockReader, log, 200))
             U.interrupt(sockReader);
 
-        executorService.shutdownNow();
+        executorSrvc.shutdownNow();
 
         spi.printStopInfo();
     }
@@ -435,7 +435,7 @@ else if (state == DISCONNECTED) {
                 else {
                     final GridFutureAdapter<Boolean> finalFut = fut;
 
-                    executorService.schedule(() -> {
+                    executorSrvc.schedule(() -> {
                         if (pingFuts.remove(nodeId, finalFut)) {
                             if (ClientImpl.this.state == DISCONNECTED)
                                 finalFut.onDone(new IgniteClientDisconnectedCheckedException(null,
@@ -2144,7 +2144,7 @@ private void tryJoin() throws InterruptedException {
             if (spi.joinTimeout > 0) {
                 final int joinCnt0 = joinCnt;
 
-                executorService.schedule(() -> {
+                executorSrvc.schedule(() -> {
                     queue.add(new JoinTimeout(joinCnt0));
                 }, spi.joinTimeout, MILLISECONDS);
             }
@@ -2746,7 +2746,7 @@ int queueSize() {
      */
     private static class JoinTimeout {
         /** */
-        private int joinCnt;
+        private final int joinCnt;
 
         /**
          * @param joinCnt Join count to compare.