Github user tillrohrmann commented on a diff in the pull request:
https://github.com/apache/flink/pull/6333#discussion_r202552483
--- Diff:
flink-runtime/src/main/java/org/apache/flink/runtime/state/KeyExtractorFunction.java
---
@@ -28,9 +28,22 @@
@FunctionalInterface
public interface KeyExtractorFunction<T> {
+ KeyExtractorFunction<? extends Keyed<?>> FOR_KEYED_OBJECTS = new
KeyExtractorFunction<Keyed<?>>() {
+ @Nonnull
+ @Override
+ public Object extractKeyFromElement(@Nonnull Keyed<?> element) {
+ return element.getKey();
+ }
+ };
--- End diff --
Could we move this extractor into its own `KeyedKeyExtractorFunction`
singleton?
---
