Hibernate Many to One Tutorial- Annotation based

Many to One Mapping Annotation:

To link one entity to another, you need to map the association property as a to one association. In the relational model, you can either use a foreign key or an association table, or (a bit less common) share the same primary key value between the two entities.

To mark an association, use @ManyToOne.

@ManyToOne(cascade = CascadeType.ALL)

Student.java

package com.candidjava.hibernate;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.Table;
@Entity
@Table(name = "STUDENT")
public class Student {
  private long studentId;
  private String studentName;
  private Address studentAddress;
  public Student() {
  }
  public Student(String studentName, Address studentAddress) {
    this.studentName = studentName;
    this.studentAddress = studentAddress;
  }
  @Id
  @GeneratedValue
  @Column(name = "STUDENT_ID")
  public long getStudentId() {
    return this.studentId;
  }
  public void setStudentId(long studentId) {
    this.studentId = studentId;
  }
  @Column(name = "STUDENT_NAME", nullable = false, length = 100)
  public String getStudentName() {
    return this.studentName;
  }
  public void setStudentName(String studentName) {
    this.studentName = studentName;
  }
  @ManyToOne(cascade = CascadeType.ALL)
  public Address getStudentAddress() {
    return this.studentAddress;
  }
  public void setStudentAddress(Address studentAddress) {
    this.studentAddress = studentAddress;
  }
}

Address.java

package com.candidjava.hibernate;
 
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;
 
@Entity
@Table(name = "ADDRESS")
public class Address {
 
  private long addressId;
  private String street;
  private String city;
  private String state;
  private String zipcode;
 
  public Address() {
  }
 
  public Address(String street, String city, String state, String zipcode) {
    this.street = street;
    this.city = city;
    this.state = state;
    this.zipcode = zipcode;
  }
 
  @Id
  @GeneratedValue
  @Column(name = "ADDRESS_ID")
  public long getAddressId() {
    return this.addressId;
  }
 
  public void setAddressId(long addressId) {
    this.addressId = addressId;
  }
 
  @Column(name = "ADDRESS_STREET", nullable = false, length = 250)
  public String getStreet() {
    return this.street;
  }
 
  public void setStreet(String street) {
    this.street = street;
  }
 
  @Column(name = "ADDRESS_CITY", nullable = false, length = 50)
  public String getCity() {
    return this.city;
  }
 
  public void setCity(String city) {
    this.city = city;
  }
 
  @Column(name = "ADDRESS_STATE", nullable = false, length = 50)
  public String getState() {
    return this.state;
  }
 
  public void setState(String state) {
    this.state = state;
  }
 
  @Column(name = "ADDRESS_ZIPCODE", nullable = false, length = 10)
  public String getZipcode() {
    return this.zipcode;
  }
 
  public void setZipcode(String zipcode) {
    this.zipcode = zipcode;
  }
 
}

save or inserting record into many to one annotation mapping

public void insertStudent(Student bk) {
    try {
      Session s = getSession();
      Transaction transaction = s.beginTransaction();
      s.save(bk);
      // s.save(b);
      transaction.commit();
 
    } catch (HibernateException e) {
      e.printStackTrace();
    }
 
  }

Get or fetch record from many to one annotation mapping

   public Student getStudent(long id) {
  Student ls = new Student();
  try {
    Session s = getSession();
    ls = (Student) s.load(Student.class, id);
    // System.out.println(ls.size());
  } catch (HibernateException e) {
    System.out.println(e.getMessage());
  }
  return ls;
}

Download

Many to one annotation example war

Many to one annotation example zip