Github user rvesse commented on a diff in the pull request:
https://github.com/apache/jena/pull/407#discussion_r183809337
--- Diff:
jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/store/DatasetGraphSwitchable.java
---
@@ -111,7 +112,8 @@ public Graph getDefaultGraph() {
@Override
public Graph getGraph(Node gn) {
- return ngCache.getOrFill(gn,
()->GraphViewSwitchable.createNamedGraph(this, gn));
+ Node key = ( gn != null ) ? gn : Quad.defaultGraphNodeGenerated;
+ return ngCache.getOrFill(gn,
()->GraphViewSwitchable.createNamedGraph(this, key));
--- End diff --
Shouldn't the first `gn` reference on this line also be changed to `key`
otherwise you are adding a potentially `null` key to the cache
---
