Java/JPA/One to One Mapping

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BiDirection One To One Mappoing

File: Address.java
import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.OneToOne;
@Entity
public class Address {
  @Id
  private int id;
  private String street;
  private String city;
  private String state;
  private String zip;
  @OneToOne(cascade=CascadeType.ALL)
  private Student student;
  
  public int getId() {
    return id;
  }
  public void setId(int id) {
    this.id = id;
  }
  public String getStreet() {
    return street;
  }
  public void setStreet(String address) {
    this.street = address;
  }
  public String getCity() {
    return city;
  }
  public void setCity(String city) {
    this.city = city;
  }
  public String getState() {
    return state;
  }
  public void setState(String state) {
    this.state = state;
  }
  public String getZip() {
    return zip;
  }
  public void setZip(String zip) {
    this.zip = zip;
  }
  public Student getStudent() {
    return student;
  }
  public void setStudent(Student student) {
    this.student = student;
  }
  public String toString() {
    return "Address id: " + getId() + ", street: " + getStreet() + ", city: " + getCity()
        + ", state: " + getState() + ", zip: " + getZip();
  }
}

File: Helper.java
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class Helper {
  public static void checkData() throws Exception {
    Class.forName("org.hsqldb.jdbcDriver");
    Connection conn = DriverManager.getConnection("jdbc:hsqldb:data/tutorial", "sa", "");
    Statement st = conn.createStatement();
    ResultSet mrs = conn.getMetaData().getTables(null, null, null, new String[] { "TABLE" });
    while (mrs.next()) {
      String tableName = mrs.getString(3);
      System.out.println("\n\n\n\nTable Name: "+ tableName);
      ResultSet rs = st.executeQuery("select * from " + tableName);
      ResultSetMetaData metadata = rs.getMetaData();
      while (rs.next()) {
        System.out.println(" Row:");
        for (int i = 0; i < metadata.getColumnCount(); i++) {
          System.out.println("    Column Name: "+ metadata.getColumnLabel(i + 1)+ ",  ");
          System.out.println("    Column Type: "+ metadata.getColumnTypeName(i + 1)+ ":  ");
          Object value = rs.getObject(i + 1);
          System.out.println("    Column Value: "+value+"\n");
        }
      }
    }
  }
}

File: Main.java
import java.util.List;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.Query;
public class Main {
  static EntityManagerFactory emf = Persistence.createEntityManagerFactory("JPAService");
  static EntityManager em = emf.createEntityManager();
  public static void main(String[] a) throws Exception {
    em.getTransaction().begin();
    
    
    Student student = new Student();
    student.setName("Joe");
    Address address = new Address();
    address.setCity("city");
    address.setStudent(student);
  //em.persist(address);
    
    student.setAddress(address);
      
    em.persist(student);
    em.flush();
    em.getTransaction().rumit();
    
    
    
    Query query = em.createQuery("SELECT e FROM Address e");
    List<Address> list = (List<Address>) query.getResultList();
    System.out.println(list.get(0).getStudent());
    
    
    em.close();
    emf.close();
    
    Helper.checkData();
  }
}

File: Student.java
import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.OneToOne;
@Entity
public class Student {
  @Id
  private int id;
  private String name;
  @OneToOne(cascade=CascadeType.ALL)
  private Address address;
  public int getId() {
    return id;
  }
  public void setId(int id) {
    this.id = id;
  }
  public String getName() {
    return name;
  }
  public void setName(String name) {
    this.name = name;
  }
  public Address getAddress() {
    return address;
  }
  public void setAddress(Address address) {
    this.address = address;
  }
  public String toString() {
    return "\n\nID:" + id + "\nName:" + name + "\n\n";
  }
}


File: persistence.xml
<persistence xmlns="http://java.sun.ru/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.ru/xml/ns/persistence http://java.sun.ru/xml/ns/persistence/persistence" version="1.0">
  <persistence-unit name="JPAService" transaction-type="RESOURCE_LOCAL">
    <properties>
      <property name="hibernate.dialect" value="org.hibernate.dialect.HSQLDialect"/>
      <property name="hibernate.hbm2ddl.auto" value="update"/>
      <property name="hibernate.connection.driver_class" value="org.hsqldb.jdbcDriver"/>
      <property name="hibernate.connection.username" value="sa"/>
      <property name="hibernate.connection.password" value=""/>
      <property name="hibernate.connection.url" value="jdbc:hsqldb:data/tutorial"/>
    </properties>
  </persistence-unit>
</persistence>





Mark Entity RelationShip As One To One

File: Address.java
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.TableGenerator;
@Entity
public class Address {
  @TableGenerator(name = "Address_Gen", table = "ID_GEN", pkColumnName = "GEN_NAME", valueColumnName = "GEN_VAL", pkColumnValue = "Addr_Gen", initialValue = 10000, allocationSize = 100)
  @Id
  @GeneratedValue(strategy = GenerationType.TABLE, generator = "Address_Gen")
  private int id;
  private String street;
  private String city;
  private String state;
  private String zip;
  public int getId() {
    return id;
  }
  public void setId(int id) {
    this.id = id;
  }
  public String getStreet() {
    return street;
  }
  public void setStreet(String address) {
    this.street = address;
  }
  public String getCity() {
    return city;
  }
  public void setCity(String city) {
    this.city = city;
  }
  public String getState() {
    return state;
  }
  public void setState(String state) {
    this.state = state;
  }
  public String getZip() {
    return zip;
  }
  public void setZip(String zip) {
    this.zip = zip;
  }
  public String toString() {
    return "Address id: " + getId() + ", street: " + getStreet() + ", city: " + getCity()
        + ", state: " + getState() + ", zip: " + getZip();
  }
}

File: Professor.java
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToOne;
import javax.persistence.TableGenerator;
@Entity
public class Professor {
  @TableGenerator(name = "Emp_Gen", table = "ID_GEN", pkColumnName = "GEN_NAME", valueColumnName = "GEN_VAL")
  @Id
  @GeneratedValue(strategy = GenerationType.TABLE, generator = "Emp_Gen")
  private int id;
  private String name;
  private long salary;
  @OneToOne
  private Address address;
  public int getId() {
    return id;
  }
  public void setId(int id) {
    this.id = id;
  }
  public String getName() {
    return name;
  }
  public void setName(String name) {
    this.name = name;
  }
  public long getSalary() {
    return salary;
  }
  public void setSalary(long salary) {
    this.salary = salary;
  }
  public Address getAddress() {
    return address;
  }
  public void setAddress(Address address) {
    this.address = address;
  }
  public String toString() {
    return "Professor id: " + getId() + " name: " + getName() + " salary: " + getSalary();
  }
}

File: ProfessorService.java
import java.util.Collection;
import javax.persistence.EntityManager;
import javax.persistence.Query;
public class ProfessorService {
  protected EntityManager em;
  public ProfessorService(EntityManager em) {
    this.em = em;
  }

  public Professor createProfessor(String name, long salary, 
          String street, String city, String state, String zip) {
      Professor emp = new Professor();
      emp.setName(name);
      emp.setSalary(salary);
      
      Address addr = new Address();
      addr.setStreet(street);
      addr.setCity(city);
      addr.setState(state);
      addr.setZip(zip);
      emp.setAddress(addr);
      em.persist(emp);
      em.persist(addr);
      
      return emp;
  }
  public void removeProfessor(int id) {
    Professor emp = findProfessor(id);
    if (emp != null) {
      em.remove(emp);
    }
  }
  public Professor raiseProfessorSalary(int id, long raise) {
    Professor emp = em.find(Professor.class, id);
    if (emp != null) {
      emp.setSalary(emp.getSalary() + raise);
    }
    return emp;
  }
  public Professor findProfessor(int id) {
    return em.find(Professor.class, id);
  }
  public Collection<Professor> findAllProfessors() {
    Query query = em.createQuery("SELECT e FROM Professor e");
    return (Collection<Professor>) query.getResultList();
  }
}

File: JPAUtil.java
import java.io.Reader;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class JPAUtil {
  Statement st;
  
  public JPAUtil() throws Exception{
    Class.forName("org.hsqldb.jdbcDriver");
    System.out.println("Driver Loaded.");
    String url = "jdbc:hsqldb:data/tutorial";
    Connection conn = DriverManager.getConnection(url, "sa", "");
    System.out.println("Got Connection.");
    st = conn.createStatement();
  }
  public void executeSQLCommand(String sql) throws Exception {
    st.executeUpdate(sql);
  }
  public void checkData(String sql) throws Exception {
    ResultSet rs = st.executeQuery(sql);
    ResultSetMetaData metadata = rs.getMetaData();
    for (int i = 0; i < metadata.getColumnCount(); i++) {
      System.out.print("\t"+ metadata.getColumnLabel(i + 1)); 
    }
    System.out.println("\n----------------------------------");
    while (rs.next()) {
      for (int i = 0; i < metadata.getColumnCount(); i++) {
        Object value = rs.getObject(i + 1);
        if (value == null) {
          System.out.print("\t       ");
        } else {
          System.out.print("\t"+value.toString().trim());
        }
      }
      System.out.println("");
    }
  }
}

File: Main.java
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
public class Main {
  public static void main(String[] a) throws Exception {
    JPAUtil util = new JPAUtil();
    EntityManagerFactory emf = Persistence.createEntityManagerFactory("ProfessorService");
    EntityManager em = emf.createEntityManager();
    ProfessorService service = new ProfessorService(em);
    em.getTransaction().begin();
    Professor emp = service.createProfessor("name", 100, 
        "street", "city", "state", "zip");
    em.getTransaction().rumit();
    System.out.println("Persisted " + emp);
    util.checkData("select * from Professor");
    util.checkData("select * from ADDRESS");
    util.checkData("select * from ID_GEN");
    
    
    em.close();
    emf.close();
  }
}



File: persistence.xml
<persistence xmlns="http://java.sun.ru/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.ru/xml/ns/persistence http://java.sun.ru/xml/ns/persistence/persistence" version="1.0">
  <persistence-unit name="JPAService" transaction-type="RESOURCE_LOCAL">
    <properties>
      <property name="hibernate.dialect" value="org.hibernate.dialect.HSQLDialect"/>
      <property name="hibernate.hbm2ddl.auto" value="update"/>
      <property name="hibernate.connection.driver_class" value="org.hsqldb.jdbcDriver"/>
      <property name="hibernate.connection.username" value="sa"/>
      <property name="hibernate.connection.password" value=""/>
      <property name="hibernate.connection.url" value="jdbc:hsqldb:data/tutorial"/>
    </properties>
  </persistence-unit>
</persistence>





One To One Bidirectional

File: ParkingSpace.java

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToOne;
@Entity
public class ParkingSpace {
    @Id @GeneratedValue(strategy=GenerationType.IDENTITY)
    private int id;
    private int lot;
    private String location;
    @OneToOne(mappedBy="parkingSpace")
    private Professor employee;
    public int getId() {
        return id;
    }
    
    public void setId(int id) {
        this.id = id;
    }
    public int getLot() {
        return lot;
    }
    public void setLot(int lot) {
        this.lot = lot;
    }
    
    public String getLocation() {
        return location;
    }
    
    public void setLocation(String deptName) {
        this.location = deptName;
    }
    public String toString() {
        return "ParkingSpace id: " + getId() + " lot: " + getLot() +
               ", location: " + getLocation();
    }
}

File: Professor.java

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToOne;
@Entity
public class Professor {
    @Id @GeneratedValue(strategy=GenerationType.IDENTITY)
    private int id;
    private String name;
    private long salary;
    
    @OneToOne 
    @JoinColumn(name="PSPACE_ID") 
    private ParkingSpace parkingSpace;
    public int getId() {
        return id;
    }
    
    public void setId(int id) {
        this.id = id;
    }
    
    public String getName() {
        return name;
    }
    
    public void setName(String name) {
        this.name = name;
    }
    public long getSalary() {
        return salary;
    }
    public void setSalary(long salary) {
        this.salary = salary;
    }
    
    public ParkingSpace getParkingSpace() {
        return parkingSpace;
    }
    
    public void setParkingSpace(ParkingSpace parkingSpace) {
        this.parkingSpace = parkingSpace;
    }
    public String toString() {
        return "Professor id: " + getId() + " name: " + getName() + 
               " with " + getParkingSpace();
    }
}

File: ProfessorService.java
import java.util.Collection;
import javax.persistence.EntityManager;
import javax.persistence.Query;
public class ProfessorService {
  protected EntityManager em;
  public ProfessorService(EntityManager em) {
    this.em = em;
  }
  public Professor createProfessor(String name, long salary) {
    Professor emp = new Professor();
    emp.setName(name);
    emp.setSalary(salary);
    em.persist(emp);
    return emp;
  }
  public Professor setProfessorParkingSpace(int empId, int spaceId) {
    Professor emp = em.find(Professor.class, empId);
    ParkingSpace pSpace = em.find(ParkingSpace.class, spaceId);
    emp.setParkingSpace(pSpace);
    return emp;
  }
  public Collection<Professor> findAllProfessors() {
    Query query = em.createQuery("SELECT e FROM Professor e");
    return (Collection<Professor>) query.getResultList();
  }
  public ParkingSpace createParkingSpace(int lot, String location) {
    ParkingSpace space = new ParkingSpace();
    space.setLot(lot);
    space.setLocation(location);
    em.persist(space);
    return space;
  }
  public Collection<ParkingSpace> findAllParkingSpaces() {
    Query query = em.createQuery("SELECT p FROM ParkingSpace p");
    return (Collection<ParkingSpace>) query.getResultList();
  }
}

File: JPAUtil.java
import java.io.Reader;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class JPAUtil {
  Statement st;
  
  public JPAUtil() throws Exception{
    Class.forName("org.hsqldb.jdbcDriver");
    System.out.println("Driver Loaded.");
    String url = "jdbc:hsqldb:data/tutorial";
    Connection conn = DriverManager.getConnection(url, "sa", "");
    System.out.println("Got Connection.");
    st = conn.createStatement();
  }
  public void executeSQLCommand(String sql) throws Exception {
    st.executeUpdate(sql);
  }
  public void checkData(String sql) throws Exception {
    ResultSet rs = st.executeQuery(sql);
    ResultSetMetaData metadata = rs.getMetaData();
    for (int i = 0; i < metadata.getColumnCount(); i++) {
      System.out.print("\t"+ metadata.getColumnLabel(i + 1)); 
    }
    System.out.println("\n----------------------------------");
    while (rs.next()) {
      for (int i = 0; i < metadata.getColumnCount(); i++) {
        Object value = rs.getObject(i + 1);
        if (value == null) {
          System.out.print("\t       ");
        } else {
          System.out.print("\t"+value.toString().trim());
        }
      }
      System.out.println("");
    }
  }
}

File: Main.java
import java.util.Collection;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
public class Main {
  public static void main(String[] a) throws Exception {
    JPAUtil util = new JPAUtil();
    EntityManagerFactory emf = Persistence.createEntityManagerFactory("ProfessorService");
    EntityManager em = emf.createEntityManager();
    ProfessorService service = new ProfessorService(em);
    em.getTransaction().begin();
    Professor emp = service.createProfessor("empName", 100);
    ParkingSpace pSpace = service.createParkingSpace(1, "location");
    Professor emp1 = service.setProfessorParkingSpace(emp.getId(), pSpace.getId());
    Collection<Professor> emps = service.findAllProfessors();
    if (emps.isEmpty()) {
      System.out.println("No Professors found ");
    } else {
      System.out.println("Found Professors: ");
      for (Professor emp2 : emps) {
        System.out.println(emp2);
      }
    }
    Collection<ParkingSpace> pSpaces = service.findAllParkingSpaces();
    if (pSpaces.isEmpty()) {
      System.out.println("No ParkingSpaces found ");
    } else {
      System.out.println("Found ParkingSpaces:");
      for (ParkingSpace pSpace1 : pSpaces) {
        System.out.println(pSpace1);
      }
    }
    util.checkData("select * from Professor");
    util.checkData("select * from ParkingSpace");
    em.getTransaction().rumit();
    em.close();
    emf.close();
  }
}


File: persistence.xml
<persistence xmlns="http://java.sun.ru/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.ru/xml/ns/persistence http://java.sun.ru/xml/ns/persistence/persistence" version="1.0">
  <persistence-unit name="JPAService" transaction-type="RESOURCE_LOCAL">
    <properties>
      <property name="hibernate.dialect" value="org.hibernate.dialect.HSQLDialect"/>
      <property name="hibernate.hbm2ddl.auto" value="update"/>
      <property name="hibernate.connection.driver_class" value="org.hsqldb.jdbcDriver"/>
      <property name="hibernate.connection.username" value="sa"/>
      <property name="hibernate.connection.password" value=""/>
      <property name="hibernate.connection.url" value="jdbc:hsqldb:data/tutorial"/>
    </properties>
  </persistence-unit>
</persistence>





One To One MappedBy

File: ParkingSpace.java

import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.OneToOne;
import javax.persistence.PrimaryKeyJoinColumn;
import javax.persistence.Table;
@Entity
public class ParkingSpace {
    @Id
    private int id;
    private int lot;
    private String location;
    @OneToOne
    @PrimaryKeyJoinColumn
    private Professor employee;
    public int getId() {
        return id;
    }
    
    public void setId(int id) {
        this.id = id;
    }
    public int getLot() {
        return lot;
    }
    public void setLot(int lot) {
        this.lot = lot;
    }
    
    public String getLocation() {
        return location;
    }
    
    public void setLocation(String deptName) {
        this.location = deptName;
    }
    public Professor getProfessor() {
        return employee;
    }
    public void setProfessor(Professor employee) {
        this.employee = employee;
    }
    
    public String toString() {
        return "ParkingSpace id: " + getId() + " lot: " + getLot() +
               ", location: " + getLocation();
    }
}

File: Professor.java

import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.OneToOne;
@Entity
public class Professor {
    @Id
    private int id;
    private String name;
    private long salary;
    
    @OneToOne(mappedBy="employee") 
    private ParkingSpace parkingSpace;
    public int getId() {
        return id;
    }
    
    public void setId(int id) {
        this.id = id;
    }
    
    public String getName() {
        return name;
    }
    
    public void setName(String name) {
        this.name = name;
    }
    public long getSalary() {
        return salary;
    }
    public void setSalary(long salary) {
        this.salary = salary;
    }
    
    public ParkingSpace getParkingSpace() {
        return parkingSpace;
    }
    
    public void setParkingSpace(ParkingSpace parkingSpace) {
        this.parkingSpace = parkingSpace;
    }
    public String toString() {
        return "Professor id: " + getId() + " name: " + getName() + 
               " with " + getParkingSpace();
    }
}

File: ProfessorService.java
import java.util.Collection;
import javax.persistence.EntityManager;
import javax.persistence.Query;
public class ProfessorService {
  protected EntityManager em;
  public ProfessorService(EntityManager em) {
    this.em = em;
  }
  public Professor createProfessor(int id, String name, long salary) {
    Professor emp = new Professor();
    emp.setId(id);
    emp.setName(name);
    emp.setSalary(salary);
    em.persist(emp);
    return emp;
  }
  public Collection<Professor> findAllProfessors() {
    Query query = em.createQuery("SELECT e FROM Professor e");
    return (Collection<Professor>) query.getResultList();
  }
  public ParkingSpace createParkingSpace(Professor emp, int lot, String location) {
    ParkingSpace space = new ParkingSpace();
    space.setId(emp.getId());
    space.setLot(lot);
    space.setLocation(location);
    emp.setParkingSpace(space);
    space.setProfessor(emp);
    em.persist(space);
    return space;
  }
  public Collection<ParkingSpace> findAllParkingSpaces() {
    Query query = em.createQuery("SELECT p FROM ParkingSpace p");
    return (Collection<ParkingSpace>) query.getResultList();
  }
}

File: JPAUtil.java
import java.io.Reader;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class JPAUtil {
  Statement st;
  
  public JPAUtil() throws Exception{
    Class.forName("org.hsqldb.jdbcDriver");
    System.out.println("Driver Loaded.");
    String url = "jdbc:hsqldb:data/tutorial";
    Connection conn = DriverManager.getConnection(url, "sa", "");
    System.out.println("Got Connection.");
    st = conn.createStatement();
  }
  public void executeSQLCommand(String sql) throws Exception {
    st.executeUpdate(sql);
  }
  public void checkData(String sql) throws Exception {
    ResultSet rs = st.executeQuery(sql);
    ResultSetMetaData metadata = rs.getMetaData();
    for (int i = 0; i < metadata.getColumnCount(); i++) {
      System.out.print("\t"+ metadata.getColumnLabel(i + 1)); 
    }
    System.out.println("\n----------------------------------");
    while (rs.next()) {
      for (int i = 0; i < metadata.getColumnCount(); i++) {
        Object value = rs.getObject(i + 1);
        if (value == null) {
          System.out.print("\t       ");
        } else {
          System.out.print("\t"+value.toString().trim());
        }
      }
      System.out.println("");
    }
  }
}

File: Main.java
import java.util.Collection;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
public class Main {
  public static void main(String[] a) throws Exception {
    JPAUtil util = new JPAUtil();
    EntityManagerFactory emf = Persistence.createEntityManagerFactory("ProfessorService");
    EntityManager em = emf.createEntityManager();
    ProfessorService service = new ProfessorService(em);
    em.getTransaction().begin();
    Professor emp = service.createProfessor(1, "empName", 100L);
    service.createParkingSpace(emp, 1, "location");
    System.out.println("Created " + emp);
    Collection<Professor> emps = service.findAllProfessors();
    if (emps.isEmpty()) {
      System.out.println("No Professors found ");
    } else {
      System.out.println("Found Professors:");
      for (Professor emp1 : emps) {
        System.out.println(emp1);
      }
    }
    Collection<ParkingSpace> pSpaces = service.findAllParkingSpaces();
    if (pSpaces.isEmpty()) {
      System.out.println("No ParkingSpaces found ");
    } else {
      System.out.println("Found ParkingSpaces:");
      for (ParkingSpace pSpace : pSpaces) {
        System.out.println(pSpace);
      }
    }
    util.checkData("select * from Professor");
    util.checkData("select * from ParkingSpace");
    em.getTransaction().rumit();
    em.close();
    emf.close();
  }
}


File: persistence.xml
<persistence xmlns="http://java.sun.ru/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.ru/xml/ns/persistence http://java.sun.ru/xml/ns/persistence/persistence" version="1.0">
  <persistence-unit name="JPAService" transaction-type="RESOURCE_LOCAL">
    <properties>
      <property name="hibernate.dialect" value="org.hibernate.dialect.HSQLDialect"/>
      <property name="hibernate.hbm2ddl.auto" value="update"/>
      <property name="hibernate.connection.driver_class" value="org.hsqldb.jdbcDriver"/>
      <property name="hibernate.connection.username" value="sa"/>
      <property name="hibernate.connection.password" value=""/>
      <property name="hibernate.connection.url" value="jdbc:hsqldb:data/tutorial"/>
    </properties>
  </persistence-unit>
</persistence>





One To One Mapping Based On Table Based ID

File: Address.java
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.TableGenerator;
@Entity
public class Address {
  @TableGenerator(name = "Address_Gen", table = "ID_GEN", pkColumnName = "GEN_NAME", valueColumnName = "GEN_VAL", pkColumnValue = "Addr_Gen", initialValue = 10000, allocationSize = 100)
  @Id
  @GeneratedValue(strategy = GenerationType.TABLE, generator = "Address_Gen")
  private int id;
  private String street;
  private String city;
  private String state;
  private String zip;
  public int getId() {
    return id;
  }
  public void setId(int id) {
    this.id = id;
  }
  public String getStreet() {
    return street;
  }
  public void setStreet(String address) {
    this.street = address;
  }
  public String getCity() {
    return city;
  }
  public void setCity(String city) {
    this.city = city;
  }
  public String getState() {
    return state;
  }
  public void setState(String state) {
    this.state = state;
  }
  public String getZip() {
    return zip;
  }
  public void setZip(String zip) {
    this.zip = zip;
  }
  public String toString() {
    return "Address id: " + getId() + ", street: " + getStreet() + ", city: " + getCity()
        + ", state: " + getState() + ", zip: " + getZip();
  }
}

File: Student.java
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToOne;
import javax.persistence.TableGenerator;
@Entity
public class Student {
  @TableGenerator(name = "Emp_Gen", table = "ID_GEN", pkColumnName = "GEN_NAME", valueColumnName = "GEN_VAL")
  @Id
  @GeneratedValue(strategy = GenerationType.TABLE, generator = "Emp_Gen")
  private int id;
  private String name;
  @OneToOne
  private Address address;
  public int getId() {
    return id;
  }
  public void setId(int id) {
    this.id = id;
  }
  public String getName() {
    return name;
  }
  public void setName(String name) {
    this.name = name;
  }
  public Address getAddress() {
    return address;
  }
  public void setAddress(Address address) {
    this.address = address;
  }
  public String toString() {
    return "\n\nID:" + id + "\nName:" + name + "\n\n";
  }
}

File: Main.java
import java.sql.Timestamp;
import java.util.List;
import java.util.UUID;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.Query;
public class Main {
  static EntityManagerFactory emf = Persistence.createEntityManagerFactory("JPAService");
  static EntityManager em = emf.createEntityManager();
  public static void main(String[] a) throws Exception {
    em.getTransaction().begin();
    
    
    Student student = new Student();
    student.setName("Joe");
    Address address = new Address();
    em.persist(address);
    
    student.setAddress(address);
      
    em.persist(student);
    em.flush();
    em.getTransaction().rumit();
    
    Query query = em.createQuery("SELECT e FROM Student e");
    List<Student> list = (List<Student>) query.getResultList();
    System.out.println(list);
    
    
    em.close();
    emf.close();
    
    Helper.checkData();
  }
}

File: Helper.java
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class Helper {
  public static void checkData() throws Exception {
    Class.forName("org.hsqldb.jdbcDriver");
    Connection conn = DriverManager.getConnection("jdbc:hsqldb:data/tutorial", "sa", "");
    Statement st = conn.createStatement();
    ResultSet mrs = conn.getMetaData().getTables(null, null, null, new String[] { "TABLE" });
    while (mrs.next()) {
      String tableName = mrs.getString(3);
      System.out.println("\n\n\n\nTable Name: "+ tableName);
      ResultSet rs = st.executeQuery("select * from " + tableName);
      ResultSetMetaData metadata = rs.getMetaData();
      while (rs.next()) {
        System.out.println(" Row:");
        for (int i = 0; i < metadata.getColumnCount(); i++) {
          System.out.println("    Column Name: "+ metadata.getColumnLabel(i + 1)+ ",  ");
          System.out.println("    Column Type: "+ metadata.getColumnTypeName(i + 1)+ ":  ");
          Object value = rs.getObject(i + 1);
          System.out.println("    Column Value: "+value+"\n");
        }
      }
    }
  }
}


File: persistence.xml
<persistence xmlns="http://java.sun.ru/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.ru/xml/ns/persistence http://java.sun.ru/xml/ns/persistence/persistence" version="1.0">
  <persistence-unit name="JPAService" transaction-type="RESOURCE_LOCAL">
    <properties>
      <property name="hibernate.dialect" value="org.hibernate.dialect.HSQLDialect"/>
      <property name="hibernate.hbm2ddl.auto" value="update"/>
      <property name="hibernate.connection.driver_class" value="org.hsqldb.jdbcDriver"/>
      <property name="hibernate.connection.username" value="sa"/>
      <property name="hibernate.connection.password" value=""/>
      <property name="hibernate.connection.url" value="jdbc:hsqldb:data/tutorial"/>
    </properties>
  </persistence-unit>
</persistence>





One To One Mapping: Lazy load

File: ParkingSpace.java

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
@Entity
public class ParkingSpace {
    @Id @GeneratedValue(strategy=GenerationType.IDENTITY)
    private int id;
    private int lot;
    private String location;
    public int getId() {
        return id;
    }
    
    public void setId(int id) {
        this.id = id;
    }
    public int getLot() {
        return lot;
    }
    public void setLot(int lot) {
        this.lot = lot;
    }
    
    public String getLocation() {
        return location;
    }
    
    public void setLocation(String deptName) {
        this.location = deptName;
    }
    public String toString() {
        return "ParkingSpace id: " + getId() + " lot: " + getLot() +
               ", location: " + getLocation();
    }
}

File: Professor.java

import static javax.persistence.FetchType.LAZY;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToOne;
@Entity
public class Professor {
    @Id @GeneratedValue(strategy=GenerationType.IDENTITY)
    private int id;
    private String name;
    private long salary;
    
    @OneToOne(fetch=LAZY)
    private ParkingSpace parkingSpace;
    public int getId() {
        return id;
    }
    
    public void setId(int id) {
        this.id = id;
    }
    
    public String getName() {
        return name;
    }
    
    public void setName(String name) {
        this.name = name;
    }
    public long getSalary() {
        return salary;
    }
    public void setSalary(long salary) {
        this.salary = salary;
    }
    
    public ParkingSpace getParkingSpace() {
        return parkingSpace;
    }
    
    public void setParkingSpace(ParkingSpace parkingSpace) {
        this.parkingSpace = parkingSpace;
    }
    public String toString() {
        return "Professor id: " + getId() + " name: " + getName() + 
               " with " + getParkingSpace();
    }
}

File: ProfessorService.java
import java.util.Collection;
import javax.persistence.EntityManager;
import javax.persistence.Query;
public class ProfessorService {
  protected EntityManager em;
  public ProfessorService(EntityManager em) {
    this.em = em;
  }
  public Professor createProfessor(String name, long salary) {
    Professor emp = new Professor();
    emp.setName(name);
    emp.setSalary(salary);
    em.persist(emp);
    return emp;
  }
  public Professor setProfessorParkingSpace(int empId, int spaceId) {
    Professor emp = em.find(Professor.class, empId);
    ParkingSpace pSpace = em.find(ParkingSpace.class, spaceId);
    emp.setParkingSpace(pSpace);
    return emp;
  }
  public Collection<Professor> findAllProfessors() {
    Query query = em.createQuery("SELECT e FROM Professor e");
    return (Collection<Professor>) query.getResultList();
  }
  public ParkingSpace createParkingSpace(int lot, String location) {
    ParkingSpace space = new ParkingSpace();
    space.setLot(lot);
    space.setLocation(location);
    em.persist(space);
    return space;
  }
  public Collection<ParkingSpace> findAllParkingSpaces() {
    Query query = em.createQuery("SELECT p FROM ParkingSpace p");
    return (Collection<ParkingSpace>) query.getResultList();
  }
}

File: JPAUtil.java
import java.io.Reader;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class JPAUtil {
  Statement st;
  
  public JPAUtil() throws Exception{
    Class.forName("org.hsqldb.jdbcDriver");
    System.out.println("Driver Loaded.");
    String url = "jdbc:hsqldb:data/tutorial";
    Connection conn = DriverManager.getConnection(url, "sa", "");
    System.out.println("Got Connection.");
    st = conn.createStatement();
  }
  public void executeSQLCommand(String sql) throws Exception {
    st.executeUpdate(sql);
  }
  public void checkData(String sql) throws Exception {
    ResultSet rs = st.executeQuery(sql);
    ResultSetMetaData metadata = rs.getMetaData();
    for (int i = 0; i < metadata.getColumnCount(); i++) {
      System.out.print("\t"+ metadata.getColumnLabel(i + 1)); 
    }
    System.out.println("\n----------------------------------");
    while (rs.next()) {
      for (int i = 0; i < metadata.getColumnCount(); i++) {
        Object value = rs.getObject(i + 1);
        if (value == null) {
          System.out.print("\t       ");
        } else {
          System.out.print("\t"+value.toString().trim());
        }
      }
      System.out.println("");
    }
  }
}

File: Main.java
import java.util.Collection;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
public class Main {
  public static void main(String[] a) throws Exception {
    JPAUtil util = new JPAUtil();
    EntityManagerFactory emf = Persistence.createEntityManagerFactory("ProfessorService");
    EntityManager em = emf.createEntityManager();
    ProfessorService service = new ProfessorService(em);
    em.getTransaction().begin();
    Professor emp = service.createProfessor("empName", 100L);
    ParkingSpace pSpace = service.createParkingSpace(1, "location");
    emp = service.setProfessorParkingSpace(emp.getId(), pSpace.getId());
    Collection<Professor> emps = service.findAllProfessors();
    if (emps.isEmpty()) {
      System.out.println("No Professors found ");
    } else {
      System.out.println("Found Professors:");
      for (Professor emp1 : emps) {
        System.out.println(emp1);
      }
    }
    Collection<ParkingSpace> pSpaces = service.findAllParkingSpaces();
    if (pSpaces.isEmpty()) {
      System.out.println("No ParkingSpaces found ");
    } else {
      System.out.println("Found ParkingSpaces:");
      for (ParkingSpace pSpace1 : pSpaces) {
        System.out.println(pSpace1);
      }
    }
    util.checkData("select * from Professor");
    util.checkData("select * from ParkingSpace");
    em.getTransaction().rumit();
    em.close();
    emf.close();
  }
}


File: persistence.xml
<persistence xmlns="http://java.sun.ru/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.ru/xml/ns/persistence http://java.sun.ru/xml/ns/persistence/persistence" version="1.0">
  <persistence-unit name="JPAService" transaction-type="RESOURCE_LOCAL">
    <properties>
      <property name="hibernate.dialect" value="org.hibernate.dialect.HSQLDialect"/>
      <property name="hibernate.hbm2ddl.auto" value="update"/>
      <property name="hibernate.connection.driver_class" value="org.hsqldb.jdbcDriver"/>
      <property name="hibernate.connection.username" value="sa"/>
      <property name="hibernate.connection.password" value=""/>
      <property name="hibernate.connection.url" value="jdbc:hsqldb:data/tutorial"/>
    </properties>
  </persistence-unit>
</persistence>





One To One Unidirectional Mapping

File: ParkingSpace.java

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
@Entity
public class ParkingSpace {
    @Id @GeneratedValue(strategy=GenerationType.IDENTITY)
    private int id;
    private int lot;
    private String location;
    public int getId() {
        return id;
    }
    
    public void setId(int id) {
        this.id = id;
    }
    public int getLot() {
        return lot;
    }
    public void setLot(int lot) {
        this.lot = lot;
    }
    
    public String getLocation() {
        return location;
    }
    
    public void setLocation(String deptName) {
        this.location = deptName;
    }
    public String toString() {
        return "ParkingSpace id: " + getId() + " lot: " + getLot() +
               ", location: " + getLocation();
    }
}

File: Professor.java

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToOne;
@Entity
public class Professor {
    @Id @GeneratedValue(strategy=GenerationType.IDENTITY)
    private int id;
    private String name;
    private long salary;
    
    @OneToOne 
    @JoinColumn(name="PSPACE_ID") 
    private ParkingSpace parkingSpace;
    public int getId() {
        return id;
    }
    
    public void setId(int id) {
        this.id = id;
    }
    
    public String getName() {
        return name;
    }
    
    public void setName(String name) {
        this.name = name;
    }
    public long getSalary() {
        return salary;
    }
    public void setSalary(long salary) {
        this.salary = salary;
    }
    
    public ParkingSpace getParkingSpace() {
        return parkingSpace;
    }
    
    public void setParkingSpace(ParkingSpace parkingSpace) {
        this.parkingSpace = parkingSpace;
    }
    public String toString() {
        return "Professor id: " + getId() + " name: " + getName() + 
               " with " + getParkingSpace();
    }
}

File: ProfessorService.java
import java.util.Collection;
import javax.persistence.EntityManager;
import javax.persistence.Query;
public class ProfessorService {
  protected EntityManager em;
  public ProfessorService(EntityManager em) {
    this.em = em;
  }
  public Professor createProfessor(String name, long salary) {
    Professor emp = new Professor();
    emp.setName(name);
    emp.setSalary(salary);
    em.persist(emp);
    return emp;
  }
  public Professor setProfessorParkingSpace(int empId, int spaceId) {
    Professor emp = em.find(Professor.class, empId);
    ParkingSpace pSpace = em.find(ParkingSpace.class, spaceId);
    emp.setParkingSpace(pSpace);
    return emp;
  }
  public Collection<Professor> findAllProfessors() {
    Query query = em.createQuery("SELECT e FROM Professor e");
    return (Collection<Professor>) query.getResultList();
  }
  public ParkingSpace createParkingSpace(int lot, String location) {
    ParkingSpace space = new ParkingSpace();
    space.setLot(lot);
    space.setLocation(location);
    em.persist(space);
    return space;
  }
  public Collection<ParkingSpace> findAllParkingSpaces() {
    Query query = em.createQuery("SELECT p FROM ParkingSpace p");
    return (Collection<ParkingSpace>) query.getResultList();
  }
}

File: JPAUtil.java
import java.io.Reader;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class JPAUtil {
  Statement st;
  
  public JPAUtil() throws Exception{
    Class.forName("org.hsqldb.jdbcDriver");
    System.out.println("Driver Loaded.");
    String url = "jdbc:hsqldb:data/tutorial";
    Connection conn = DriverManager.getConnection(url, "sa", "");
    System.out.println("Got Connection.");
    st = conn.createStatement();
  }
  public void executeSQLCommand(String sql) throws Exception {
    st.executeUpdate(sql);
  }
  public void checkData(String sql) throws Exception {
    ResultSet rs = st.executeQuery(sql);
    ResultSetMetaData metadata = rs.getMetaData();
    for (int i = 0; i < metadata.getColumnCount(); i++) {
      System.out.print("\t"+ metadata.getColumnLabel(i + 1)); 
    }
    System.out.println("\n----------------------------------");
    while (rs.next()) {
      for (int i = 0; i < metadata.getColumnCount(); i++) {
        Object value = rs.getObject(i + 1);
        if (value == null) {
          System.out.print("\t       ");
        } else {
          System.out.print("\t"+value.toString().trim());
        }
      }
      System.out.println("");
    }
  }
}

File: Main.java
import java.util.Collection;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
public class Main {
  public static void main(String[] a) throws Exception {
    JPAUtil util = new JPAUtil();
    EntityManagerFactory emf = Persistence.createEntityManagerFactory("ProfessorService");
    EntityManager em = emf.createEntityManager();
    ProfessorService service = new ProfessorService(em);
    em.getTransaction().begin();
    Professor emp = service.createProfessor("empName", 100);
    ParkingSpace pSpace = service.createParkingSpace(1, "location");
    Professor emp1 = service.setProfessorParkingSpace(emp.getId(), pSpace.getId());
    Collection<Professor> emps = service.findAllProfessors();
    if (emps.isEmpty()) {
      System.out.println("No Professors found ");
    } else {
      System.out.println("Found Professors: ");
      for (Professor emp2 : emps) {
        System.out.println(emp2);
      }
    }
    Collection<ParkingSpace> pSpaces = service.findAllParkingSpaces();
    if (pSpaces.isEmpty()) {
      System.out.println("No ParkingSpaces found ");
    } else {
      System.out.println("Found ParkingSpaces:");
      for (ParkingSpace pSpace1 : pSpaces) {
        System.out.println(pSpace1);
      }
    }
    util.checkData("select * from Professor");
    util.checkData("select * from ParkingSpace");
    em.getTransaction().rumit();
    em.close();
    emf.close();
  }
}


File: persistence.xml
<persistence xmlns="http://java.sun.ru/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.ru/xml/ns/persistence http://java.sun.ru/xml/ns/persistence/persistence" version="1.0">
  <persistence-unit name="JPAService" transaction-type="RESOURCE_LOCAL">
    <properties>
      <property name="hibernate.dialect" value="org.hibernate.dialect.HSQLDialect"/>
      <property name="hibernate.hbm2ddl.auto" value="update"/>
      <property name="hibernate.connection.driver_class" value="org.hsqldb.jdbcDriver"/>
      <property name="hibernate.connection.username" value="sa"/>
      <property name="hibernate.connection.password" value=""/>
      <property name="hibernate.connection.url" value="jdbc:hsqldb:data/tutorial"/>
    </properties>
  </persistence-unit>
</persistence>





Retrieve One To One Mapped Entity

File: Address.java
import javax.persistence.Entity;
import javax.persistence.Id;
@Entity
public class Address {
  @Id
  private int id;
  private String street;
  private String city;
  private String state;
  private String zip;
  public int getId() {
    return id;
  }
  public void setId(int id) {
    this.id = id;
  }
  public String getStreet() {
    return street;
  }
  public void setStreet(String address) {
    this.street = address;
  }
  public String getCity() {
    return city;
  }
  public void setCity(String city) {
    this.city = city;
  }
  public String getState() {
    return state;
  }
  public void setState(String state) {
    this.state = state;
  }
  public String getZip() {
    return zip;
  }
  public void setZip(String zip) {
    this.zip = zip;
  }
  public String toString() {
    return "Address id: " + getId() + ", street: " + getStreet() + ", city: " + getCity()
        + ", state: " + getState() + ", zip: " + getZip();
  }
}

File: Student.java
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.OneToOne;
@Entity
public class Student {
  @Id
  private int id;
  private String name;
  @OneToOne
  private Address address;
  public int getId() {
    return id;
  }
  public void setId(int id) {
    this.id = id;
  }
  public String getName() {
    return name;
  }
  public void setName(String name) {
    this.name = name;
  }
  public Address getAddress() {
    return address;
  }
  public void setAddress(Address address) {
    this.address = address;
  }
  public String toString() {
    return "\n\nID:" + id + "\nName:" + name + "\n\n";
  }
}

File: Main.java
import java.sql.Timestamp;
import java.util.List;
import java.util.UUID;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.Query;
public class Main {
  static EntityManagerFactory emf = Persistence.createEntityManagerFactory("JPAService");
  static EntityManager em = emf.createEntityManager();
  public static void main(String[] a) throws Exception {
    em.getTransaction().begin();
    
    
    Student student = new Student();
    student.setName("Joe");
    Address address = new Address();
    em.persist(address);
    
    student.setAddress(address);
      
    em.persist(student);
    em.flush();
    em.getTransaction().rumit();
    
    
    
    Query query = em.createQuery("SELECT e FROM Student e");
    List<Student> list = (List<Student>) query.getResultList();
    System.out.println(list.get(0).getAddress());
    
    
    em.close();
    emf.close();
    
    Helper.checkData();
  }
}

File: Helper.java
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
public class Helper {
  public static void checkData() throws Exception {
    Class.forName("org.hsqldb.jdbcDriver");
    Connection conn = DriverManager.getConnection("jdbc:hsqldb:data/tutorial", "sa", "");
    Statement st = conn.createStatement();
    ResultSet mrs = conn.getMetaData().getTables(null, null, null, new String[] { "TABLE" });
    while (mrs.next()) {
      String tableName = mrs.getString(3);
      System.out.println("\n\n\n\nTable Name: "+ tableName);
      ResultSet rs = st.executeQuery("select * from " + tableName);
      ResultSetMetaData metadata = rs.getMetaData();
      while (rs.next()) {
        System.out.println(" Row:");
        for (int i = 0; i < metadata.getColumnCount(); i++) {
          System.out.println("    Column Name: "+ metadata.getColumnLabel(i + 1)+ ",  ");
          System.out.println("    Column Type: "+ metadata.getColumnTypeName(i + 1)+ ":  ");
          Object value = rs.getObject(i + 1);
          System.out.println("    Column Value: "+value+"\n");
        }
      }
    }
  }
}


File: persistence.xml
<persistence xmlns="http://java.sun.ru/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.ru/xml/ns/persistence http://java.sun.ru/xml/ns/persistence/persistence" version="1.0">
  <persistence-unit name="JPAService" transaction-type="RESOURCE_LOCAL">
    <properties>
      <property name="hibernate.dialect" value="org.hibernate.dialect.HSQLDialect"/>
      <property name="hibernate.hbm2ddl.auto" value="update"/>
      <property name="hibernate.connection.driver_class" value="org.hsqldb.jdbcDriver"/>
      <property name="hibernate.connection.username" value="sa"/>
      <property name="hibernate.connection.password" value=""/>
      <property name="hibernate.connection.url" value="jdbc:hsqldb:data/tutorial"/>
    </properties>
  </persistence-unit>
</persistence>


Источник — «http://jexp.ru/index.php?title=Java/JPA/One_to_One_Mapping&oldid=8963»