migrate GraphDatabaseFacade.getRelationshipById

community/kernel-api/src/main/java/org/neo4j/internal/kernel/api/Read.java

@@ -75,6 +75,7 @@ void nodeIndexSeek( IndexReference index, NodeValueIndexCursor cursor, IndexOrde
 
     /**
      * Checks if a node exists in the database
+     *
      * @param reference The reference of the node to check
      * @return <tt>true</tt> if the node exists, otherwise <tt>false</tt>
      */
@@ -88,6 +89,14 @@ void nodeIndexSeek( IndexReference index, NodeValueIndexCursor cursor, IndexOrde
      */
     void singleRelationship( long reference, RelationshipScanCursor cursor );
 
+    /**
+     * Checks if a relationship exists in the database
+     *
+     * @param reference The reference of the relationship to check
+     * @return <tt>true</tt> if the relationship exists, otherwise <tt>false</tt>
+     */
+    boolean relationshipExists( long reference );
+
     void allRelationshipsScan( RelationshipScanCursor cursor );
 
     Scan<RelationshipScanCursor> allRelationshipsScan();

community/kernel-api/src/test/java/org/neo4j/internal/kernel/api/helpers/StubRead.java

@@ -103,6 +103,12 @@ public void singleRelationship( long reference, RelationshipScanCursor cursor )
         throw new UnsupportedOperationException();
     }
 
+    @Override
+    public boolean relationshipExists( long reference )
+    {
+        throw new UnsupportedOperationException();
+    }
+
     @Override
     public void allRelationshipsScan( RelationshipScanCursor cursor )
     {

community/kernel/src/main/java/org/neo4j/kernel/impl/api/store/StorageLayer.java

@@ -545,6 +545,12 @@ public boolean nodeExists( long id )
         return nodeStore.isInUse( id );
     }
 
+    @Override
+    public boolean relationshipExists( long id )
+    {
+        return relationshipStore.isInUse( id );
+    }
+
     @Override
     public PrimitiveIntSet relationshipTypes( StorageStatement statement, NodeItem node )
     {

community/kernel/src/main/java/org/neo4j/kernel/impl/factory/GraphDatabaseFacade.java

@@ -321,18 +321,17 @@ public Relationship getRelationshipById( long id )
             throw new NotFoundException( format( "Relationship %d not found", id ),
                     new EntityNotFoundException( EntityType.RELATIONSHIP, id ) );
         }
-        try ( Statement statement = statementContext.get() )
+
+        KernelTransaction ktx = statementContext.getKernelTransactionBoundToThisThread( true );
+        assertTransactionOpen( ktx );
+        try ( Statement ignore = statementContext.get() )
         {
-            try
-            {
-                RelationshipProxy relationship = newRelationshipProxy( id );
-                statement.readOperations().relationshipVisit( id, relationship );
-                return relationship;
-            }
-            catch ( EntityNotFoundException e )
+            if ( !ktx.dataRead().relationshipExists( id ) )
             {
-                throw new NotFoundException( format( "Relationship %d not found", id ), e );
+                throw new NotFoundException( format( "Relationship %d not found", id ),
+                        new EntityNotFoundException( EntityType.RELATIONSHIP, id ) );
             }
+            return newRelationshipProxy( id );
         }
     }
 

community/kernel/src/main/java/org/neo4j/kernel/impl/newapi/AllStoreHolder.java

@@ -115,6 +115,26 @@ else if ( txState.nodeIsAddedInThisTx( reference ) )
         return storeReadLayer.nodeExists( reference );
     }
 
+    @Override
+    public boolean relationshipExists( long reference )
+    {
+        ktx.assertOpen();
+
+        if ( hasTxStateWithChanges() )
+        {
+            TransactionState txState = txState();
+            if ( txState.relationshipIsDeletedInThisTx( reference ) )
+            {
+                return false;
+            }
+            else if ( txState.relationshipIsAddedInThisTx( reference ) )
+            {
+                return true;
+            }
+        }
+        return storeReadLayer.relationshipExists( reference );
+    }
+
     @Override
     long graphPropertiesReference()
     {

community/kernel/src/main/java/org/neo4j/storageengine/api/StoreReadLayer.java

@@ -384,6 +384,8 @@ DoubleLongRegister indexSample( LabelSchemaDescriptor descriptor, DoubleLongRegi
 
     boolean nodeExists( long id );
 
+    boolean relationshipExists( long id );
+
     PrimitiveIntSet relationshipTypes( StorageStatement statement, NodeItem node );
 
     void degrees( StorageStatement statement, NodeItem nodeItem, DegreeVisitor visitor );

community/kernel/src/test/java/org/neo4j/kernel/impl/newapi/MockStore.java

@@ -195,6 +195,12 @@ public boolean nodeExists( long id )
         throw new UnsupportedOperationException( "not implemented" );
     }
 
+    @Override
+    public boolean relationshipExists( long reference )
+    {
+        throw new UnsupportedOperationException( "not implemented" );
+    }
+
     private abstract static class Record<R extends AbstractBaseRecord>
     {
         abstract void initialize( R record );