Объединение трех таблиц в Hibernate

Question

Я новичок в hibernate и пытался достичь ниже, я создал три таблицы

1) Пользователь 2) Проект 3) User_project_Mapping

Теперь мы должны быть в состоянии искать все пользователи сопоставлены с проектами. Чтобы достичь этого, я создал три классифицированных объекта

1) UserEntity -> он содержит отношение OnetoMany для UserProjectMapEntity 2) UserProjectMapEnitiy -> Он содержит отношение один ко многим в ProjectEntity 3) ProjectEntity

Теперь все работает хорошо, я могу создать нового пользователя и т. Д. c.

Теперь есть возможность, что человек хочет проверить, сколько пользователей работает над конкретным проектом? Нужно ли создавать нового пользователя, сущность ProjectMap пользователя и ProjectEntities?

@Entity(name = "UserDetails")
@Table(name= "main_userdetails")
public class UserDetails {
    @Id
    @Column(name = "USER_ID")
    int UseriD;
    @Column(name = "Name")
    String Name;
    @Column(name = "EMAIL")
    String Email;
    @Column(name = "MARATIAL_STATUS")
    String Maratial_Status;
    @Column(name = "SPOUCE_NAME")
    String Spouce_Name;
    @Column(name = "DATE_OF_BIRTH")
    Date Date_Of_Birth;
    @Column(name = "ADDRESS1")
    String Address1;
    @Column(name = "ADDRESS2")
    String Address2;
    @Column(name = "CITY")
    String City;
    @Column(name = "PROVINCE")
    String Province;
    @Column(name = "COUNTRY")
    String Country;
    @Column(name = "Last_Login")
    Date Last_Login;


     @OneToMany(targetEntity= UserProjectMapping.class)
     @JoinColumn(name = "USER_ID")
     List<UserProjectMapping> userProjectMapping = new ArrayList<UserProjectMapping>();


    public UserDetails(int useriD, String name, String email, String maratial_Status, String spouce_Name,
            Date date_Of_Birth, String address1, String address2, String city, String province, String country,
            Date last_Login, List<UserProjectMapping> userProjectMapping) {
        super();
        UseriD = useriD;
        Name = name;
        Email = email;
        Maratial_Status = maratial_Status;
        Spouce_Name = spouce_Name;
        Date_Of_Birth = date_Of_Birth;
        Address1 = address1;
        Address2 = address2;
        City = city;
        Province = province;
        Country = country;
        Last_Login = last_Login;
        this.userProjectMapping = userProjectMapping;
    }

    public List<UserProjectMapping> getUserProjectMapping() {
        return userProjectMapping;
    }

    public void setUserProjectMapping(List<UserProjectMapping> userProjectMapping) {
        this.userProjectMapping = userProjectMapping;
    }


    public UserDetails(int useriD, String name, String email, String maratial_Status, String spouce_Name,
            Date date_Of_Birth, String address1, String address2, String city, String province, String country,
            Date last_Login) {
        super();
        UseriD = useriD;
        Name = name;
        Email = email;
        Maratial_Status = maratial_Status;
        Spouce_Name = spouce_Name;
        Date_Of_Birth = date_Of_Birth;
        Address1 = address1;
        Address2 = address2;
        City = city;
        Province = province;
        Country = country;
        Last_Login = last_Login;
    }


    public UserDetails(int useriD) {
        super();
        UseriD = useriD;
    }

    public UserDetails() {}


    public int getUseriD() {
        return UseriD;
    }
    public void setUseriD(int useriD) {
        UseriD = useriD;
    }
    public String getName() {
        return Name;
    }
    public void setName(String name) {
        Name = name;
    }
    public String getEmail() {
        return Email;
    }
    public void setEmail(String email) {
        Email = email;
    }
    public String getMaratial_Status() {
        return Maratial_Status;
    }
    public void setMaratial_Status(String maratial_Status) {
        Maratial_Status = maratial_Status;
    }
    public String getSpouce_Name() {
        return Spouce_Name;
    }
    public void setSpouce_Name(String spouce_Name) {
        Spouce_Name = spouce_Name;
    }
    public Date getDate_Of_Birth() {
        return Date_Of_Birth;
    }
    public void setDate_Of_Birth(Date date_Of_Birth) {
        Date_Of_Birth = date_Of_Birth;
    }
    public String getAddress1() {
        return Address1;
    }
    public void setAddress1(String address1) {
        Address1 = address1;
    }
    public String getAddress2() {
        return Address2;
    }
    public void setAddress2(String address2) {
        Address2 = address2;
    }
    public String getCity() {
        return City;
    }
    public void setCity(String city) {
        City = city;
    }
    public String getProvince() {
        return Province;
    }
    public void setProvince(String province) {
        Province = province;
    }
    public String getCountry() {
        return Country;
    }
    public void setCountry(String country) {
        Country = country;
    }
    public Date getLast_Login() {
        return Last_Login;
    }
    public void setLast_Login(Date last_Login) {
        Last_Login = last_Login;
    }


}

@Entity(name= "UserProjectMapping")
@Table(name = "userproject_mapping")

public class UserProjectMapping {


    @Id
    @Column(name= "ProjectID")
    String ProjectId;


     @OneToMany(targetEntity= ProjectDetails.class)
     @JoinColumn(name = "ProjectID")
     List<ProjectDetails> projectdetails = new ArrayList<ProjectDetails>();

    public UserProjectMapping() {}



    public String getProjectId() {
        return ProjectId;
    }

    public void setProjectId(String projectId) {
        ProjectId = projectId;
    }

    public List<ProjectDetails> getProjectdetails() {
        return projectdetails;
    }

    public void setProjectdetails(List<ProjectDetails> projectdetails) {
        this.projectdetails = projectdetails;
    }


}

@Table(name ="project_details")
@Entity(name = "ProjectDetails")
public class ProjectDetails {

    @Id
    @Column(name = "ProjectID")
    String ProjectID;

    @Column(name = "Project_Description")
    String ProjectDescription;

    @Column(name = "Project_Start_Date")
    Date ProjectStartDate;

    @Column(name = "Project_End_Date")
    Date ProjectEndDate;

    @Column(name = "OffShore_Project_Manager")
    String OffShoreProjectManager;

    @Column(name = "Onsite_Project_Manager")
    String OnsiteProjectManager;


    public ProjectDetails() {}



    public ProjectDetails(String projectID, String projectDescription, Date projectStartDate, Date projectEndDate,
            String offShoreProjectManager, String onsiteProjectManager) {
        super();
        ProjectID = projectID;
        ProjectDescription = projectDescription;
        ProjectStartDate = projectStartDate;
        ProjectEndDate = projectEndDate;
        OffShoreProjectManager = offShoreProjectManager;
        OnsiteProjectManager = onsiteProjectManager;
    }

    public String getProjectID() {
        return ProjectID;
    }

    public void setProjectID(String projectID) {
        ProjectID = projectID;
    }

    public String getProjectDescription() {
        return ProjectDescription;
    }

    public void setProjectDescription(String projectDescription) {
        ProjectDescription = projectDescription;
    }

    public Date getProjectStartDate() {
        return ProjectStartDate;
    }

    public void setProjectStartDate(Date projectStartDate) {
        ProjectStartDate = projectStartDate;
    }

    public Date getProjectEndDate() {
        return ProjectEndDate;
    }

    public void setProjectEndDate(Date projectEndDate) {
        ProjectEndDate = projectEndDate;
    }

    public String getOffShoreProjectManager() {
        return OffShoreProjectManager;
    }

    public void setOffShoreProjectManager(String offShoreProjectManager) {
        OffShoreProjectManager = offShoreProjectManager;
    }

    public String getOnsiteProjectManager() {
        return OnsiteProjectManager;
    }

    public void setOnsiteProjectManager(String onsiteProjectManager) {
        OnsiteProjectManager = onsiteProjectManager;
    }





}

public class UserDetailsDAO {

    SessionFactory factory = new Configuration()
            .configure("hibernate.cfg.xml")
            .addAnnotatedClass(UserDetails.class)
            .addAnnotatedClass(UserProjectMapping.class)
            .addAnnotatedClass(ProjectDetails.class)
            .buildSessionFactory();




    public List<UserDetails> getUserDetails() {

        Session session = factory.getCurrentSession();
        session.beginTransaction();
        List<UserDetails> lst = session.createQuery("from UserDetails").getResultList();

        return lst;
    }




    public void SaveUser(UserDetails userdetails) {
        Session session = factory.getCurrentSession();
        session.beginTransaction();
        session.save(userdetails);
        session.getTransaction().commit();
        System.out.println("The deatils have been saved");
    }

}