JPA 2.1 Coverter 注解

@Converter(autoApply = true)
public class VehicleConverter implements AttributeConverter<Vehicle, String> {

    @Override
    public String convertToDatabaseColumn(Vehicle vehicle) {
        switch (vehicle) {
        case BUS:
            return "B";
        case CAR:
            return "C";
        case PLANE:
            return "P";
        case TRAIN:
            return "T";
        default:
            throw new IllegalArgumentException("Unknown value: " + vehicle);
        }
    }

    @Override
    public Vehicle convertToEntityAttribute(String dbData) {
        switch (dbData) {
        case "B":
            return Vehicle.BUS;
        case "C":
            return Vehicle.CAR;
        case "P":
            return Vehicle.PLANE;
        case "T":
            return Vehicle.TRAIN;
        default:
            throw new IllegalArgumentException("Unknown value: " + dbData);
        }
    }

}