JPA PostgreSQL point attribute converter

Question

I have an entity class City with a property coordinates I'd like to persist using JPA :

@Entity
public class City {
  public static class Point {
    protected double x;
    protected double y;
    // getters and setters
  }

  protected Point coordinates;
  // getter and setter
}

To do that I created an attribute converter to transform Point to PGpoint and vice verca :

@Converter(autoApply = true)
public class PointToPGpointConverter implements AttributeConverter<Point, PGpoint> {
  @Override
  public PGpoint convertToDatabaseColumn(Point point) {
    return new PGpoint(point.getX(), point.getX());
  }

  @Override
  public Point convertToEntityAttribute(PGpoint point) {
    return new Point(point.x, point.y);
  }
}

But when fetching data, a java.io.StreamCorruptedException is thrown :

invalid stream header: 2834382E

The value corresponds to the hexadecimal representation of "(48.", which is the start of one of the persisted coordinates.

Edit

I believe the serializer is waiting for an Object bytes array but it received a String one. The method throwing the exception is ObjectInputStream.readStreamHeader(). Its OpenJDK implementation (openjdk-jdk11/ObjectInputStream.java#L870) is :

protected void readStreamHeader()
  throws IOException, StreamCorruptedException
{
  short s0 = bin.readShort();
  short s1 = bin.readShort();
  if (s0 != STREAM_MAGIC || s1 != STREAM_VERSION) {
    throw new StreamCorruptedException(
      String.format("invalid stream header: %04X%04X", s0, s1));
  }
}

It waits for a STREAM_MAGIC. According to https://stackoverflow.com/a/57631495/6286793

STREAM_MAGIC denotes start of serialzed content.

The problem is when receiving tuples, the PGStream.receiveTupleV3() method gets the bytes array of the string value of the POINT field, not a serialized object.

Is that a bug?

JPA PostgreSQL point attribute converter

Edit

0 Answers0