[Java, FlatBuffers 23.5.26, Mac OS 14.3] getByKey returns null while accessing using vector index works

[PratikBarhate]

Programming language : Java17 Operating systems : Mac OS 14.3 CPU: M1 Pro FlatBuffer (flatc) version : 23.5.26 JDK : openjdk 17.0.10 2024-01-16 LTS

FlatBuffer Schema

namespace com.example.testing;

table Scores {
  key_col: string (key);
  score : double;
}

table Data {
  id: string (required);
  test_vector: [double] (required);
  scores : [Scores] (required);
}

root_type Data;

De-serialization code :-

  public static double [] flatBufferToData(byte[] data) {
      ByteBuffer byteBuffer = ByteBuffer.wrap(data);
      Data testFeature = Data.getRootAsTestFeature(byteBuffer);
      String testId = testFeature.id();
      DoubleVector vector = testFeature.embeddingVectorVector();
      Scores.Vector scoreVec = testFeature.scoresVector();
      System.out.println("Index access " + scoreVec.get(50).score());
      System.out.println("Index access key " + scoreVec.get(50).keyCol());
      double[] testAccess = new double[4];
      testAccess[0] = vector.get(10);
      System.out.println("key_" + 10);
      testAccess[1] = scoreVec.getByKey("key_" + 10).score();
      testAccess[2] = vector.get(10);
      testAccess[3] = scoreVec.getByKey("key_" + 10).score();
      return testAccess;
  }

Standard output :-

Index access 0.20687898819703532
Index access key key_14
key_10
<failure>

java.lang.NullPointerException: ...

We are able to read the data when accessed using the vector index, although while accessing the data using getByKey returns null.