I have two Entity classes, each for my Table. They both are OneToOne-Mapped. When I read the Data, am always getting the other table's value as null.
These are my SQLs
CREATE TABLE driver_master (
  unique_driver_id VARCHAR(60) PRIMARY KEY,
  driver_name TEXT,
  mobile_number VARCHAR (20),
  vehicle_number TEXT,
  vehicle_make TEXT,
  seating_capacity INTEGER (10),
  creation_time DATETIME
)
CREATE TABLE user_master (
  user_id MEDIUMINT AUTO_INCREMENT PRIMARY KEY,
  user_name TEXT,
  password VARCHAR (20),
  unique_driver_id VARCHAR(60),
  FOREIGN KEY (unique_driver_id) REFERENCES driver_master(unique_driver_id)
)
These are my Entity classes
DriverMaster.java
@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
@Entity
@Table(name = "driver_master")
public class DriverMaster {
    @Id
    @GeneratedValue(generator = "uuid2")
    @GenericGenerator(name = "uuid2", strategy = "org.hibernate.id.UUIDGenerator")
    @Column(name = "unique_driver_id")
    UUID id;
    @Column(name = "driver_name")
    String driverName;
    @Column(name = "mobile_number")
    String mobileNumber;
    @Column(name = "vehicle_number")
    String vehicleNumber;
    @Column(name = "vehicle_make")
    String vehicleMake;
    @Column(name = "seating_capacity")
    Integer seatingCapacity;
    @Column(name = "creation_time")
    OffsetDateTime creationTime;
    @OneToOne(cascade = CascadeType.ALL, mappedBy = "driverMaster")
    UserMaster userMaster;
}
UserMaster.java
@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
@Entity
@Table(name = "user_master")
public class UserMaster {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "user_id")
    Long id;
    @Column(name = "user_name")
    String userName;
    @Column(name = "password")
    String password;
    @OneToOne(fetch = FetchType.EAGER)
    @JoinColumn(name = "unique_driver_id", nullable = false)
    DriverMaster driverMaster;
}
This is my DriverMasterRepository
public interface DriverMasterRepository extends CrudRepository<DriverMaster, Long> {
    DriverMaster findById(UUID id);
}
This is my UserMasterRepository
public interface UserMasterRepository extends CrudRepository<UserMaster, Long> {
    UserMaster findById(Long id);
}
I am creating DriverMaster and UserMaster at the same time. Code Snippet below
public DriverMaster create() {
        UserMaster userMaster = UserMaster.builder()
                .userName("xxxxx")
                .password("xxxx").build();
        DriverMaster driverMaster = DriverMaster.builder().driverName("TestDriver")
                .creationTime(ZonedDateTime.now().toOffsetDateTime())
                .seatingCapacity(8)
                .mobileNumber("xxxxxxx")
                .vehicleNumber("xxxx")
                .vehicleMake("xxxx")
                 .userMaster(userMaster)
                .build();
        return driverUserService.create(driverMaster);
    }
When i access each repository and get the data, the data for that particular table is getting populated while the referenced Object is always coming as Null.
After creation of DriverMaster, I couldn't get UserMaster within DriverMaster, it is always coming as null .
The REST Response below shows that UserMaster within DriverMaster is coming as Null
   {
    "id": "0d97073b-6ae2-47a9-b751-0313fd9e8ba2",
    "driverName": "TestDriver",
    "mobileNumber": "11111",
    "vehicleNumber": "111",
    "vehicleMake": "figo",
    "seatingCapacity": 8,
    "creationTime": "2018-02-16T15:56:50.331Z",
    "userMaster": null
}
 
    