Improved readability and typo fixes in CsvInput and thereabout

community/import-tool/src/test/java/org/neo4j/tooling/SimpleDataGenerator.java

@@ -58,15 +58,15 @@ public Function<Range,InputNode[]>  nodes()
     {
         return batch -> new SimpleDataGeneratorBatch<>( nodeHeader, batch.getStart(), randomSeed + batch.getStart(),
                 nodeCount, labels, relationshipTypes,
-                new InputNodeDeserialization( SimpleDataGenerator.this, nodeHeader, groups, idType.idsAreExternal() ),
+                new InputNodeDeserialization( nodeHeader, SimpleDataGenerator.this, groups, idType.idsAreExternal() ),
                 new InputNode[batch.getSize()] ).get();
     }
 
     public Function<Range,InputRelationship[]> relationships()
     {
         return batch -> new SimpleDataGeneratorBatch<>( relationshipHeader, batch.getStart(),
                 randomSeed + batch.getStart(), nodeCount, labels, relationshipTypes,
-                new InputRelationshipDeserialization( SimpleDataGenerator.this, relationshipHeader, groups ),
+                new InputRelationshipDeserialization( relationshipHeader, SimpleDataGenerator.this, groups ),
                 new InputRelationship[batch.getSize()] ).get();
     }
 

community/kernel/src/main/java/org/neo4j/unsafe/impl/batchimport/input/InputEntity.java

@@ -55,6 +55,10 @@ public InputEntity( String sourceDescription, long sourceLineNumber, long source
         this.firstPropertyId = firstPropertyId;
     }
 
+    /**
+     * @return properties on this entity. Properties sits in one array with alternating keys (even indexes)
+     * and values (odd indexes).
+     */
     public Object[] properties()
     {
         return properties;

community/kernel/src/main/java/org/neo4j/unsafe/impl/batchimport/input/csv/Configuration.java

@@ -69,11 +69,11 @@ public char arrayDelimiter()
         }
     };
 
-    class Overriden extends org.neo4j.csv.reader.Configuration.Overridden implements Configuration
+    class Overridden extends org.neo4j.csv.reader.Configuration.Overridden implements Configuration
     {
         private final Configuration defaults;
 
-        public Overriden( Configuration defaults )
+        public Overridden( Configuration defaults )
         {
             super( defaults );
             this.defaults = defaults;

community/kernel/src/main/java/org/neo4j/unsafe/impl/batchimport/input/csv/CsvInput.java

@@ -108,12 +108,15 @@ public InputIterable<InputNode> nodes()
             @Override
             public InputIterator<InputNode> iterator()
             {
-                DeserializerFactory<InputNode> factory = (dataStream, dataHeader, decorator, validator) ->
-                        new InputEntityDeserializer<>( dataHeader, dataStream, config.delimiter(),
-                                new InputNodeDeserialization( dataStream, dataHeader, groups, idType.idsAreExternal() ),
-                                decorator, validator, badCollector );
+                DeserializerFactory<InputNode> factory = (dataHeader, dataStream, decorator, validator) ->
+                {
+                        InputNodeDeserialization deserialization =
+                                new InputNodeDeserialization( dataHeader, dataStream, groups, idType.idsAreExternal() );
+                        return new InputEntityDeserializer<>( dataHeader, dataStream, config.delimiter(),
+                                deserialization, decorator, validator, badCollector );
+                };
                 return new InputGroupsDeserializer<>( nodeDataFactory.iterator(), nodeHeaderFactory, config,
-                        idType, maxProcessors, factory,Validators.<InputNode>emptyValidator(), InputNode.class );
+                        idType, maxProcessors, factory, Validators.<InputNode>emptyValidator(), InputNode.class );
             }
 
             @Override
@@ -132,10 +135,13 @@ public InputIterable<InputRelationship> relationships()
             @Override
             public InputIterator<InputRelationship> iterator()
             {
-                DeserializerFactory<InputRelationship> factory = (dataStream, dataHeader, decorator, validator) ->
-                        new InputEntityDeserializer<>( dataHeader, dataStream, config.delimiter(),
-                                new InputRelationshipDeserialization( dataStream, dataHeader, groups ),
-                                decorator, validator, badCollector );
+                DeserializerFactory<InputRelationship> factory = (dataHeader, dataStream, decorator, validator) ->
+                {
+                        InputRelationshipDeserialization deserialization =
+                                new InputRelationshipDeserialization( dataHeader, dataStream, groups );
+                        return new InputEntityDeserializer<>( dataHeader, dataStream, config.delimiter(),
+                                deserialization, decorator, validator, badCollector );
+                };
                 return new InputGroupsDeserializer<>( relationshipDataFactory.iterator(), relationshipHeaderFactory,
                         config, idType, maxProcessors, factory, new InputRelationshipValidator(),
                         InputRelationship.class );

community/kernel/src/main/java/org/neo4j/unsafe/impl/batchimport/input/csv/ExternalPropertiesDecorator.java

@@ -27,6 +27,7 @@
 import org.neo4j.unsafe.impl.batchimport.input.UpdateBehaviour;
 
 import static org.neo4j.csv.reader.CharSeekers.charSeeker;
+import static org.neo4j.unsafe.impl.batchimport.input.InputEntityDecorators.NO_NODE_DECORATOR;
 
 /**
  * Pulls in properties from an external CSV source and amends them to the "main" input nodes.
@@ -47,12 +48,15 @@
  * <Pre>
  * Then properties {@code abc@somewhere} and {@code def@somewhere} will be amended to input node {@code 1}
  * and {@code ghi@someplace} to input node {@code 3}.
+ *
+ * NOTE that order the input data (where we key on ID) is assumed to be the same, there are no checks
+ * for trying to verify this constraint though.
  */
 public class ExternalPropertiesDecorator implements Decorator<InputNode>
 {
     private final InputEntityDeserializer<InputNode> deserializer;
     private final UpdateBehaviour updateBehaviour;
-    private volatile InputNode currentExternal;
+    private InputNode currentExternal;
 
     /**
      * @param headerFactory creates a {@link Header} that will specify which field is the {@link Type#ID id field}
@@ -65,8 +69,8 @@ public ExternalPropertiesDecorator( DataFactory<InputNode> data, Header.Factory
         CharSeeker dataStream = charSeeker( data.create( config ).stream(), config, true );
         Header header = headerFactory.create( dataStream, config, idType );
         this.deserializer = new InputEntityDeserializer<>( header, dataStream, config.delimiter(),
-                new InputNodeDeserialization( dataStream, header, new Groups(), idType.idsAreExternal() ),
-                value -> value, Validators.<InputNode>emptyValidator(), badCollector );
+                new InputNodeDeserialization( header, dataStream, new Groups(), idType.idsAreExternal() ),
+                NO_NODE_DECORATOR, Validators.<InputNode>emptyValidator(), badCollector );
     }
 
     @Override

community/kernel/src/main/java/org/neo4j/unsafe/impl/batchimport/input/csv/InputGroupsDeserializer.java

@@ -55,7 +55,7 @@ class InputGroupsDeserializer<ENTITY extends InputEntity>
     @FunctionalInterface
     public interface DeserializerFactory<ENTITY extends InputEntity>
     {
-        InputEntityDeserializer<ENTITY> create( CharSeeker dataStream, Header dataHeader,
+        InputEntityDeserializer<ENTITY> create( Header dataHeader, CharSeeker dataStream,
                 Function<ENTITY,ENTITY> decorator, Validator<ENTITY> validator );
     }
 
@@ -94,7 +94,7 @@ protected InputIterator<ENTITY> createNestedIterator( DataFactory<ENTITY> dataFa
             Header dataHeader = headerFactory.create( dataStream, config, idType );
 
             InputEntityDeserializer<ENTITY> input =
-                    factory.create( dataStream, dataHeader, data.decorator(), validator );
+                    factory.create( dataHeader, dataStream, data.decorator(), validator );
             // It's important that we assign currentInput before calling initialize(), so that if something
             // goes wrong in initialize() and our close() is called we close it properly.
             currentInput = input;

community/kernel/src/main/java/org/neo4j/unsafe/impl/batchimport/input/csv/InputNodeDeserialization.java

@@ -44,7 +44,7 @@ public class InputNodeDeserialization extends InputEntityDeserialization<InputNo
     private String[] labels = new String[10];
     private int labelsCursor;
 
-    public InputNodeDeserialization( SourceTraceability source, Header header, Groups groups, boolean idsAreExternal )
+    public InputNodeDeserialization( Header header, SourceTraceability source, Groups groups, boolean idsAreExternal )
     {
         super( source );
         this.header = header;

community/kernel/src/main/java/org/neo4j/unsafe/impl/batchimport/input/csv/InputRelationshipDeserialization.java

@@ -39,7 +39,7 @@ public class InputRelationshipDeserialization extends InputEntityDeserialization
     private Object startNode;
     private Object endNode;
 
-    public InputRelationshipDeserialization( SourceTraceability source, Header header, Groups groups )
+    public InputRelationshipDeserialization( Header header, SourceTraceability source, Groups groups )
     {
         super( source );
         this.header = header;

community/kernel/src/main/java/org/neo4j/unsafe/impl/batchimport/input/csv/ParallelInputEntityDeserializer.java

@@ -99,7 +99,7 @@ public ParallelInputEntityDeserializer( Data<ENTITY> data, Header.Factory header
                 // to cater for decorators which may be mutable and sensitive to ordering, while still putting
                 // the work of decorating and validating on the processing threads as to not affect performance.
                 InputEntityDeserializer<ENTITY> chunkDeserializer =
-                        factory.create( seeker, header, batchDecorator, batchValidator );
+                        factory.create( header, seeker, batchDecorator, batchValidator );
                 chunkDeserializer.initialize();
                 List<ENTITY> entities = new ArrayList<>();
                 while ( chunkDeserializer.hasNext() )

community/kernel/src/test/java/org/neo4j/unsafe/impl/batchimport/input/csv/CsvInputBatchImportIT.java

@@ -116,7 +116,7 @@ IdType.STRING, lowBufferSize( COMMAS ), silentBadCollector( 0 ),
     private org.neo4j.unsafe.impl.batchimport.input.csv.Configuration lowBufferSize(
             org.neo4j.unsafe.impl.batchimport.input.csv.Configuration actual )
     {
-        return new org.neo4j.unsafe.impl.batchimport.input.csv.Configuration.Overriden( actual )
+        return new org.neo4j.unsafe.impl.batchimport.input.csv.Configuration.Overridden( actual )
         {
             @Override
             public int bufferSize()

community/kernel/src/test/java/org/neo4j/unsafe/impl/batchimport/input/csv/CsvInputTest.java

@@ -795,7 +795,7 @@ public void shouldTreatEmptyQuotedStringsAsNullIfConfiguredTo() throws Exception
         Iterable<DataFactory<InputNode>> data = DataFactories.nodeData( CsvInputTest.<InputNode>data(
                 ":ID,one,two,three\n" +
                 "1,\"\",,value" ) );
-        Configuration config = config( new Configuration.Overriden( COMMAS )
+        Configuration config = config( new Configuration.Overridden( COMMAS )
         {
             @Override
             public boolean emptyQuotedStringsAsNull()
@@ -994,7 +994,7 @@ public InputNode apply( InputNode from ) throws RuntimeException
 
     private Configuration config( Configuration config )
     {
-        return new Configuration.Overriden( config )
+        return new Configuration.Overridden( config )
         {
             @Override
             public boolean multilineFields()

community/kernel/src/test/java/org/neo4j/unsafe/impl/batchimport/input/csv/DataFactoriesTest.java

@@ -283,7 +283,7 @@ private CharSeeker seeker( String data )
 
     private static Configuration withBufferSize( Configuration config, final int bufferSize )
     {
-        return new Configuration.Overriden( config )
+        return new Configuration.Overridden( config )
         {
             @Override
             public int bufferSize()

community/kernel/src/test/java/org/neo4j/unsafe/impl/batchimport/input/csv/ExternalPropertiesDecoratorIT.java

@@ -53,7 +53,7 @@ public void shouldDecorateExternalPropertiesInParallelProcessingCsvInput() throw
         int processors = 5;
         Collector collector = mock( Collector.class );
         int count = 1000;
-        Configuration config = new Configuration.Overriden( Configuration.COMMAS )
+        Configuration config = new Configuration.Overridden( Configuration.COMMAS )
         {
             @Override
             public int bufferSize()
@@ -86,6 +86,7 @@ public int bufferSize()
                 assertHasProperty( node, "extra", node.id() + "-decorated" );
                 if ( i == 0 )
                 {
+                    // This code is equal to nodes.setProcessors( processors ) (a method which doesn't exist)
                     nodes.processors( processors - nodes.processors( 0 ) );
                 }
             }

community/kernel/src/test/java/org/neo4j/unsafe/impl/batchimport/input/csv/ExternalPropertiesDecoratorTest.java

@@ -31,7 +31,7 @@
 import org.neo4j.unsafe.impl.batchimport.input.InputEntity;
 import org.neo4j.unsafe.impl.batchimport.input.InputNode;
 import org.neo4j.unsafe.impl.batchimport.input.UpdateBehaviour;
-import org.neo4j.unsafe.impl.batchimport.input.csv.Configuration.Overriden;
+import org.neo4j.unsafe.impl.batchimport.input.csv.Configuration.Overridden;
 
 import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertEquals;
@@ -131,9 +131,9 @@ private Supplier<CharReadable> readable( final String data )
         return () -> Readables.wrap( new StringReader( data ) );
     }
 
-    private Overriden config()
+    private Overridden config()
     {
-        return new Configuration.Overriden( Configuration.COMMAS )
+        return new Configuration.Overridden( Configuration.COMMAS )
         {
             @Override
             public int bufferSize()

community/kernel/src/test/java/org/neo4j/unsafe/impl/batchimport/input/csv/InputGroupsDeserializerTest.java

@@ -52,7 +52,7 @@ public void shouldBeAbleToAskForSourceInformationEvenBetweenTwoSources() throws
         final AtomicReference<InputGroupsDeserializer<InputNode>> deserializerTestHack = new AtomicReference<>( null );
         InputGroupsDeserializer<InputNode> deserializer = new InputGroupsDeserializer<>(
                 data.iterator(), defaultFormatNodeFileHeader(), lowBufferSize( COMMAS ), INTEGER,
-                Runtime.getRuntime().availableProcessors(), (stream,header,decorator,validator) ->
+                Runtime.getRuntime().availableProcessors(), (header,stream,decorator,validator) ->
                 {
                     // This is the point where the currentInput field in InputGroupsDeserializer was null
                     // so ensure that's no longer the case, just by poking those source methods right here and now.
@@ -82,7 +82,7 @@ public void shouldBeAbleToAskForSourceInformationEvenBetweenTwoSources() throws
 
     private Configuration lowBufferSize( Configuration conf )
     {
-        return new Configuration.Overriden( conf )
+        return new Configuration.Overridden( conf )
         {
             @Override
             public int bufferSize()

community/kernel/src/test/java/org/neo4j/unsafe/impl/batchimport/input/csv/ParallelInputEntityDeserializerTest.java

@@ -55,7 +55,7 @@ public void shouldParseDataInParallel() throws Exception
         // GIVEN
         int entities = 500;
         Data<InputNode> data = testData( entities );
-        Configuration config = new Configuration.Overriden( COMMAS )
+        Configuration config = new Configuration.Overridden( COMMAS )
         {
             @Override
             public int bufferSize()
@@ -68,13 +68,13 @@ public int bufferSize()
         Groups groups = new Groups();
         Set<Thread> observedProcessingThreads = new CopyOnWriteArraySet<>();
         int threads = 4;
-        DeserializerFactory<InputNode> deserializerFactory = (chunk,header,decorator,validator) ->
+        DeserializerFactory<InputNode> deserializerFactory = (header,chunk,decorator,validator) ->
         {
             observedProcessingThreads.add( Thread.currentThread() );
             // Make sure there will be 4 different processing threads doing this
             while ( observedProcessingThreads.size() < threads );
             return new InputEntityDeserializer<>( header, chunk, config.delimiter(),
-                    new InputNodeDeserialization( chunk, header, groups, idType.idsAreExternal() ), decorator,
+                    new InputNodeDeserialization( header, chunk, groups, idType.idsAreExternal() ), decorator,
                     validator, badCollector );
         };
         try ( ParallelInputEntityDeserializer<InputNode> deserializer = new ParallelInputEntityDeserializer<>( data,