Set of small cleanups

Make some classes static, close file reader, use entry set iterators

community/command-line/src/main/java/org/neo4j/commandline/Util.java

@@ -21,6 +21,7 @@
 
 import java.io.File;
 import java.io.IOException;
+import java.io.InputStream;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.Properties;
@@ -109,7 +110,7 @@ public static String neo4jVersion()
         Properties props = new Properties();
         try
         {
-            props.load( Util.class.getResourceAsStream( "/org/neo4j/commandline/build.properties" ) );
+            loadProperties( props );
             return props.getProperty( "neo4jVersion" );
         }
         catch ( IOException e )
@@ -118,4 +119,12 @@ public static String neo4jVersion()
             throw new RuntimeException( e );
         }
     }
+
+    private static void loadProperties( Properties props ) throws IOException
+    {
+        try ( InputStream resource = Util.class.getResourceAsStream( "/org/neo4j/commandline/build.properties" ) )
+        {
+            props.load( resource );
+        }
+    }
 }

community/kernel/src/main/java/org/neo4j/diagnostics/DiagnosticsReporter.java

@@ -66,11 +66,11 @@ public void dump( Set<String> classifiers, Path destination, DiagnosticsReporter
         }
 
         // Add additional sources
-        for ( String classifier : additionalSources.keySet() )
+        for ( Map.Entry<String,List<DiagnosticsReportSource>> classifier : additionalSources.entrySet() )
         {
-            if ( classifiers.contains( "all" ) || classifiers.contains( classifier ) )
+            if ( classifiers.contains( "all" ) || classifiers.contains( classifier.getKey() ) )
             {
-                sources.addAll( additionalSources.get( classifier ) );
+                sources.addAll( classifier.getValue() );
             }
         }
 

community/kernel/src/main/java/org/neo4j/kernel/impl/coreapi/TxStateTransactionDataSnapshot.java

@@ -40,8 +40,8 @@
 import org.neo4j.kernel.api.KernelTransaction;
 import org.neo4j.kernel.api.exceptions.EntityNotFoundException;
 import org.neo4j.kernel.impl.api.KernelTransactionImplementation;
-import org.neo4j.kernel.impl.core.NodeProxy;
 import org.neo4j.kernel.impl.core.EmbeddedProxySPI;
+import org.neo4j.kernel.impl.core.NodeProxy;
 import org.neo4j.kernel.impl.core.RelationshipProxy;
 import org.neo4j.kernel.impl.locking.Lock;
 import org.neo4j.storageengine.api.NodeItem;
@@ -465,7 +465,7 @@ public String toString()
         }
     }
 
-    private class RelationshipPropertyEntryView implements PropertyEntry<Relationship>
+    private static class RelationshipPropertyEntryView implements PropertyEntry<Relationship>
     {
         private final Relationship relationship;
         private final String key;

community/kernel/src/main/java/org/neo4j/kernel/impl/index/labelscan/CompositeLabelScanValueIterator.java

@@ -102,7 +102,7 @@ public void close()
         toClose.clear();
     }
 
-    private class IdAndSource implements Comparable<IdAndSource>
+    private static class IdAndSource implements Comparable<IdAndSource>
     {
         private long latestReturned;
         private final PrimitiveLongIterator source;

community/kernel/src/main/java/org/neo4j/kernel/impl/index/schema/NativeNonUniqueSchemaIndexPopulator.java

@@ -40,15 +40,12 @@
 class NativeNonUniqueSchemaIndexPopulator<KEY extends NativeSchemaKey, VALUE extends NativeSchemaValue>
         extends NativeSchemaIndexPopulator<KEY,VALUE>
 {
-    private final IndexSamplingConfig samplingConfig;
-    private boolean updateSampling;
     private NonUniqueIndexSampler sampler;
 
     NativeNonUniqueSchemaIndexPopulator( PageCache pageCache, FileSystemAbstraction fs, File storeFile, Layout<KEY,VALUE> layout,
             IndexSamplingConfig samplingConfig, SchemaIndexProvider.Monitor monitor, IndexDescriptor descriptor, long indexId )
     {
         super( pageCache, fs, storeFile, layout, monitor, descriptor, indexId );
-        this.samplingConfig = samplingConfig;
         this.sampler = new DefaultNonUniqueIndexSampler( samplingConfig.sampleSizeLimit() );
     }
 

community/kernel/src/main/java/org/neo4j/kernel/impl/index/schema/fusion/FusionIndexReader.java

@@ -176,7 +176,7 @@ public boolean hasFullNumberPrecision( IndexQuery... predicates )
     /**
      * Combine multiple progressor to act like one single logical progressor seen from clients perspective.
      */
-    private class BridgingIndexProgressor implements IndexProgressor.NodeValueClient, IndexProgressor
+    private static class BridgingIndexProgressor implements IndexProgressor.NodeValueClient, IndexProgressor
     {
         private final NodeValueClient client;
         private final int[] keys;

community/kernel/src/main/java/org/neo4j/kernel/impl/store/id/ReadOnlyIdGeneratorFactory.java

@@ -74,7 +74,7 @@ public IdGenerator get( IdType idType )
         return idGenerators.get( idType );
     }
 
-    class ReadOnlyIdGenerator implements IdGenerator
+    static class ReadOnlyIdGenerator implements IdGenerator
     {
         private final long highId;
         private final long defragCount;

community/kernel/src/main/java/org/neo4j/kernel/impl/storemigration/participant/NativeLabelScanStoreMigrator.java

@@ -160,7 +160,7 @@ private static File getLuceneStoreDirectory( File storeRootDir )
         return new File( new File( new File( storeRootDir, "schema" ), "label" ), "lucene" );
     }
 
-    private class MonitoredFullLabelStream extends FullLabelStream
+    private static class MonitoredFullLabelStream extends FullLabelStream
     {
 
         private final ProgressReporter progressReporter;

community/kernel/src/main/java/org/neo4j/kernel/impl/storemigration/participant/StoreMigrator.java

@@ -740,7 +740,7 @@ private void copyWithPageCache( File sourceFile, File targetFile ) throws IOExce
         }
     }
 
-    private class BatchImporterProgressMonitor extends CoarseBoundedProgressExecutionMonitor
+    private static class BatchImporterProgressMonitor extends CoarseBoundedProgressExecutionMonitor
     {
         private final ProgressReporter progressReporter;
 

community/kernel/src/main/java/org/neo4j/kernel/impl/util/concurrent/LockWaitStrategies.java

@@ -49,8 +49,8 @@ public void apply( long iteration ) throws AcquireLockTimeoutException
     },
     INCREMENTAL_BACKOFF
     {
-        private final int spinIterations = 1000;
-        private final long multiplyUntilIteration = spinIterations + 2;
+        private static final int spinIterations = 1000;
+        private static final long multiplyUntilIteration = spinIterations + 2;
 
         @Override
         public void apply( long iteration ) throws AcquireLockTimeoutException

community/kernel/src/main/java/org/neo4j/kernel/impl/util/dbstructure/DbStructureCollector.java

@@ -331,7 +331,7 @@ public int hashCode()
         }
     }
 
-    private class IndexStatistics
+    private static class IndexStatistics
     {
         private final double uniqueValuesPercentage;
         private final long size;

community/kernel/src/main/java/org/neo4j/unsafe/batchinsert/internal/BatchInserterImpl.java

@@ -59,8 +59,6 @@
 import org.neo4j.io.pagecache.tracing.PageCacheTracer;
 import org.neo4j.io.pagecache.tracing.cursor.PageCursorTracerSupplier;
 import org.neo4j.kernel.api.exceptions.index.IndexEntryConflictException;
-import org.neo4j.kernel.api.exceptions.schema.AlreadyConstrainedException;
-import org.neo4j.kernel.api.exceptions.schema.CreateConstraintFailureException;
 import org.neo4j.kernel.api.index.IndexEntryUpdate;
 import org.neo4j.kernel.api.index.IndexPopulator;
 import org.neo4j.kernel.api.index.PropertyAccessor;
@@ -1303,7 +1301,7 @@ public void forceFlush()
 
     private static class IndexPopulatorWithSchema extends IndexPopulator.Adapter implements LabelSchemaSupplier
     {
-        private final int batchSize = 1_000;
+        private static final int batchSize = 1_000;
         private final IndexPopulator populator;
         private final IndexDescriptor index;
         private Collection<IndexEntryUpdate<?>> batchedUpdates = new ArrayList<>( batchSize );

community/kernel/src/main/java/org/neo4j/unsafe/impl/batchimport/cache/idmapping/string/StringEncoder.java

@@ -36,7 +36,7 @@ public class StringEncoder implements Encoder
 
     // fixed values
     private final int numCodes;
-    private final int encodingThreshold = 7;
+    private static final int encodingThreshold = 7;
 
     // data changing over time, potentially with each encoding
     private final byte[] reMap = new byte[256];

enterprise/fulltext-addon/src/main/java/org/neo4j/kernel/api/impl/fulltext/integrations/bloom/BloomProcedures.java

@@ -23,11 +23,11 @@
 import java.util.function.Function;
 import java.util.stream.Stream;
 
+import org.neo4j.internal.kernel.api.InternalIndexState;
 import org.neo4j.kernel.api.impl.fulltext.FulltextProvider;
 import org.neo4j.kernel.api.impl.fulltext.ReadOnlyFulltext;
 import org.neo4j.kernel.api.impl.fulltext.ScoreEntityIterator;
 import org.neo4j.kernel.api.impl.fulltext.ScoreEntityIterator.ScoreEntry;
-import org.neo4j.internal.kernel.api.InternalIndexState;
 import org.neo4j.procedure.Context;
 import org.neo4j.procedure.Description;
 import org.neo4j.procedure.Name;
@@ -156,7 +156,7 @@ public static class PropertyOutput
         }
     }
 
-    public class StatusOutput
+    public static class StatusOutput
     {
         public final String state;
 

enterprise/metrics/src/main/java/org/neo4j/metrics/source/db/BoltMetrics.java

@@ -87,7 +87,7 @@ public void stop()
         monitors.removeMonitorListener( boltMonitor );
     }
 
-    private class BoltMetricsMonitor implements MonitoredWorkerFactory.SessionMonitor
+    private static class BoltMetricsMonitor implements MonitoredWorkerFactory.SessionMonitor
     {
         final AtomicLong sessionsStarted = new AtomicLong();