Github user aljoscha commented on a diff in the pull request:
https://github.com/apache/flink/pull/5097#discussion_r156090203
--- Diff:
flink-core/src/main/java/org/apache/flink/api/java/typeutils/TypeExtractor.java
---
@@ -1822,13 +1828,15 @@ private static Type
materializeTypeVariable(ArrayList<Type> typeHierarchy, TypeV
* OR
* - there are getter and setter methods for the field.
*
+ * Returns a message why the given field is not valid. Otherwise an
empty option for valid fields.
+ *
* @param f field to check
* @param clazz class of field
* @param typeHierarchy type hierarchy for materializing generic types
*/
- private boolean isValidPojoField(Field f, Class<?> clazz,
ArrayList<Type> typeHierarchy) {
- if(Modifier.isPublic(f.getModifiers())) {
- return true;
+ private static Optional<String> analyzePojoField(Field f, Class<?>
clazz, ArrayList<Type> typeHierarchy) {
--- End diff --
Shouldn't this be an `Either` to be in line with other methods in this
class. An Optional that actually contains something in case of failure seems a
bit strange.
---
