What is the purpose of the change

Flink's protobuf format fails when processing messages compiled with protobuf-java's field naming conflict resolution. When proto schemas contain certain field patterns, protoc appends field number suffixes to accessor methods (e.g.,getStatus1(),getTags4List()), but Flink's codegen assumes canonical names (getStatus(),getTagsList()). Conflict scenarios:

• Repeated field vs*_list/*_count fields -> numbered suffixes
• Enum field +*_value field -> both get numbered suffixes (protobuf-java 4.30.0+)

This affects users with conflict-prone schemas on protobuf-java 3.x+ (repeated field conflicts) and 4.30.0+ (enum field conflicts).

Brief change log

• AddedPbFieldConflictResolver with caching for conflict-aware accessor resolution
• Refactored deserializer/serializer codegen to use conflict-aware accessors

Verifying this change

This change added tests and can be verified as follows:

• Addedtest_field_conflict.proto with field conflict scenarios
• Generated Java classes with protoc 4.32.1 to verify accessor name matching
• AddedFieldConflictProtoToRowTest (14 tests) andFieldConflictRowToProtoTest (4 tests)
• All tests pass with protobuf-java 4.32.1

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency):no
• The public API, i.e., is any changed class annotated with@Public(Evolving):no
• The serializers:no (the changes only affect which accessor methods are called during codegen, not the serialization format or behavior)
• The runtime per-record code paths (performance sensitive):no
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Kubernetes/Yarn, ZooKeeper:no
• The S3 file system connector:no

Documentation

• Does this pull request introduce a new feature?no
• If yes, how is the feature documented?not applicable