Add collect to RawCursor

Simplify code

community/kernel/src/main/java/org/neo4j/kernel/api/txstate/TransactionCountingStateVisitor.java

@@ -23,7 +23,7 @@
 import java.util.function.Consumer;
 
 import org.neo4j.collection.primitive.Primitive;
-import org.neo4j.collection.primitive.PrimitiveIntCollections;
+import org.neo4j.collection.primitive.PrimitiveIntCollection;
 import org.neo4j.collection.primitive.PrimitiveIntSet;
 import org.neo4j.cursor.Cursor;
 import org.neo4j.kernel.api.exceptions.EntityNotFoundException;
@@ -69,28 +69,22 @@ public void visitCreatedNode( long id )
     public void visitDeletedNode( long id )
     {
         counts.incrementNodeCount( ANY_LABEL, -1 );
-        statement.acquireSingleNodeCursor( id ).forAll( node ->
-        {
-            PrimitiveIntSet set =
-                    node.labels().mapReduce( Primitive.intSet(), LabelItem::getAsInt, ( labelId, current ) ->
-                    {
-                        current.add( labelId );
-                        counts.incrementNodeCount( labelId, -1 );
-                        return current;
-                    } );
-
-            int[] labelIds = PrimitiveIntCollections.asArray( set.iterator() );
-            node.degrees().forAll( degree ->
-            {
-                for ( int labelId : labelIds )
-                {
-                    updateRelationshipsCountsFromDegrees( degree.type(), labelId, -degree.outgoing(),
-                            -degree.incoming() );
-                }
-            } );
+        statement.acquireSingleNodeCursor( id ).forAll( this::decrementCountForLabelsAndRelationships );
+        super.visitDeletedNode( id );
+    }
 
+    private void decrementCountForLabelsAndRelationships( NodeItem node )
+    {
+        PrimitiveIntSet labelIds = node.labels().collect( Primitive.intSet(), ( label ) ->
+        {
+            int labelId = label.getAsInt();
+            counts.incrementNodeCount( labelId, -1 );
+            return labelId;
         } );
-        super.visitDeletedNode( id );
+
+        node.degrees().forAll(
+                degree -> updateRelationshipsCountsFromDegrees( labelIds, degree.type(), -degree.outgoing(),
+                        -degree.incoming() ) );
     }
 
     @Override
@@ -149,14 +143,20 @@ public void visitNodeLabelChanges( long id, final Set<Integer> added, final Set<
         super.visitNodeLabelChanges( id, added, removed );
     }
 
-    private void updateRelationshipsCountsFromDegrees( int type, int label, long outgoing, long incoming )
+    private void updateRelationshipsCountsFromDegrees( PrimitiveIntCollection labels, int type, long outgoing,
+            long incoming )
+    {
+        labels.visitKeys( (label) -> updateRelationshipsCountsFromDegrees( type, label, outgoing, incoming ) );
+    }
+    private boolean updateRelationshipsCountsFromDegrees( int type, int label, long outgoing, long incoming )
     {
         // untyped
         counts.incrementRelationshipCount( label, ANY_RELATIONSHIP_TYPE, ANY_LABEL, outgoing );
         counts.incrementRelationshipCount( ANY_LABEL, ANY_RELATIONSHIP_TYPE, label, incoming );
         // typed
         counts.incrementRelationshipCount( label, type, ANY_LABEL, outgoing );
         counts.incrementRelationshipCount( ANY_LABEL, type, label, incoming );
+        return true;
     }
 
     private void updateRelationshipCount( long startNode, int type, long endNode, int delta )

community/kernel/src/test/java/org/neo4j/kernel/impl/api/state/LabelTransactionStateTest.java

@@ -30,6 +30,9 @@
 import java.util.Map;
 import java.util.function.IntSupplier;
 
+import org.neo4j.collection.primitive.Primitive;
+import org.neo4j.collection.primitive.PrimitiveIntCollections;
+import org.neo4j.collection.primitive.PrimitiveIntSet;
 import org.neo4j.collection.primitive.PrimitiveLongCollections;
 import org.neo4j.kernel.api.exceptions.EntityNotFoundException;
 import org.neo4j.kernel.api.index.IndexDescriptor;
@@ -354,10 +357,13 @@ private void commitLabels( Integer... labels ) throws Exception
         commitLabels( labels( nodeId, labels ) );
     }
 
-    private void assertLabels( Integer... labels ) throws EntityNotFoundException
+    private void assertLabels( int... labels ) throws EntityNotFoundException
     {
-        txContext.nodeCursorById( state, nodeId ).forAll( node -> assertEquals( asSet( labels ),
-                node.labels().mapReduce( new HashSet<>(), IntSupplier::getAsInt, this::addToCollection ) ) );
+        txContext.nodeCursorById( state, nodeId ).forAll( node ->
+        {
+            PrimitiveIntSet collect = node.labels().collect( Primitive.intSet(), IntSupplier::getAsInt );
+            assertEquals( PrimitiveIntCollections.asSet( labels ), collect );
+        } );
 
         txContext.nodeCursorById( state, nodeId ).forAll( node ->
         {
@@ -367,10 +373,4 @@ private void assertLabels( Integer... labels ) throws EntityNotFoundException
             }
         } );
     }
-
-    private <T, C extends Collection<T>> C addToCollection( T value, C collection)
-    {
-        collection.add( value );
-        return collection;
-    }
 }

community/kernel/src/test/java/org/neo4j/kernel/impl/api/store/DiskLayerLabelTest.java

@@ -26,6 +26,9 @@
 import java.util.Set;
 import java.util.function.IntSupplier;
 
+import org.neo4j.collection.primitive.Primitive;
+import org.neo4j.collection.primitive.PrimitiveIntCollections;
+import org.neo4j.collection.primitive.PrimitiveIntSet;
 import org.neo4j.collection.primitive.PrimitiveLongCollections;
 import org.neo4j.collection.primitive.PrimitiveLongIterator;
 import org.neo4j.cursor.Cursor;
@@ -66,18 +69,11 @@ public void should_be_able_to_list_labels_for_node() throws Exception
         // THEN
         disk.newStatement().acquireSingleNodeCursor( nodeId ).forAll( node ->
         {
-            Set<Integer> actual = node.labels().mapReduce( new HashSet<>(), IntSupplier::getAsInt,
-                    this::addToCollection );
-            assertEquals( new HashSet<>( asList( labelId1, labelId2 ) ), actual );
+            PrimitiveIntSet actual = node.labels().collect( Primitive.intSet(), IntSupplier::getAsInt );
+            assertEquals( PrimitiveIntCollections.asSet( new int[]{labelId1, labelId2} ), actual );
         } );
     }
 
-    private <T, C extends Collection<T>> C addToCollection( T value, C collection)
-    {
-        collection.add( value );
-        return collection;
-    }
-
     @Test
     public void should_be_able_to_get_label_name_for_label() throws Exception
     {

community/primitive-collections/src/main/java/org/neo4j/collection/primitive/PrimitiveIntVisitor.java

@@ -19,6 +19,7 @@
  */
 package org.neo4j.collection.primitive;
 
+@FunctionalInterface
 public interface PrimitiveIntVisitor<E extends Exception>
 {
     /**

community/primitive-collections/src/main/java/org/neo4j/cursor/RawCursor.java

@@ -22,7 +22,12 @@
 import java.util.function.BiFunction;
 import java.util.function.Consumer;
 import java.util.function.Function;
+import java.util.function.IntFunction;
 import java.util.function.Supplier;
+import java.util.function.ToIntFunction;
+
+import org.neo4j.collection.primitive.PrimitiveIntCollection;
+import org.neo4j.collection.primitive.PrimitiveIntSet;
 
 /**
  * A cursor is an object that moves to point to different locations in a data structure.
@@ -55,6 +60,22 @@ default void forAll( Consumer<T> consumer ) throws EXCEPTION
         mapForAll( Function.identity(), consumer );
     }
 
+    default <R extends PrimitiveIntSet> R collect( R set, ToIntFunction<T> map ) throws EXCEPTION
+    {
+        try
+        {
+            while ( next() )
+            {
+                set.add( map.applyAsInt( get() ) );
+            }
+            return set;
+        }
+        finally
+        {
+            close();
+        }
+    }
+
     default <R, E> E mapReduce( E initialValue, Function<T,R> map, BiFunction<R,E,E> reduce ) throws EXCEPTION
     {
         try