Representing Parent Child Relationship in Spring JPA - spring

Question

I have the following scenario. I have a parent class User.java which represents user table. I have two child classes - Doctor.java and Patient.java. The data for these classes are in 'user' table. The mapping between patient and doctor is provided in doctorpatient table. And this mapping can be ManyToMany. This 'doctorpatient' table is represented by DoctorPatient.java class
I need to map my doctor and patient class in such a way that my doctor class should return all patient for a particular doctor and patient class should return all doctors for a particular patient.
I am new to hibernate and would appreciate any help.
User.java
#Entity
#Table(name = "User")
#Inheritance(strategy = InheritanceType.SINGLE_TABLE)
public class User {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long userId;
#Column(name="UserName", nullable = false, length = 16)
private String userName;
#Column(name="FirstName", nullable = false, length = 45)
private String firstName;
#Column(name="LastName", nullable = false, length = 45)
private String lastName;
#Column(name="Email", nullable = false, length = 45)
private String email;
// Getters and Setters
}
Doctor.java
public class Doctor extends User {
#OneToMany(mappedBy="doctor")
List<DoctorPatient> patientList;
//Getters and Setters
}
Patient.java
public class Patient extends User {
#OneToMany(mappedBy="patient")
List<DoctorPatient> doctorsList;
//Getters and Setters
}
DoctorPatient.java
#Entity
#Table(DoctorPatient)
public class DoctorPatient {
#EmbeddedId
private DoctorPatientId doctorPatientId;
#ManyToOne(targetEntity = Doctor.class)
#JoinColumn(name="doctorId")
private Doctor doctor;
#ManyToOne(targetEntity = Patient.class)
#JoinColumn(name="patientId")
private Patient patient;
//Getter Setters
}
Create command for DoctorPatient table
CREATE TABLE 'DoctorPatient' (
'DoctorId''INT(11) NOT NULL,
'PatientId' INT(11) NOT NULL,
PRIMARY KEY ('DoctorId', 'PatientId'),
INDEX 'FK_Doctor_idx' ('DoctorId'),
INDEX 'FK_Patient_idx' ('PatientId'),
CONSTRAINT 'FK_Patient' FOREIGN KEY ('PatientId') REFERENCES 'User' ('UserId'),
CONSTRAINT 'FK_Doctor' FOREIGN KEY ('DoctorId') REFERENCES 'User' ('UserId')
)
Currently for each doctor, I am getting the patientid (userId) from the DoctorPatient table using which I need to query the user table to get the patient details.
Similarly for patients, I am able to retrieve only doctorid (UserId) from DoctorPatient table. Then I need to iterate through the list and hit the User table to get complete details.
Solution
Updated classes
Patient.java
public class Patient extends User {
#ManyToMany
#JoinTable(name="DoctorPatient", joinColumns= {#JoinColumn(name="PatientId") }, inverseJoinColumns={ #JoinColumn(name="DoctorId") } )
private Set<Doctor> DoctorList = new HashSet<>();
//Getters and Setters
}
Doctor.java
public class Doctor extends User {
#ManyToMany(mappedBy="DoctorList")
private Set<Patient> patients = new HashSet<>();
//Getters and Setters
}