Java Tutorial/JPA/Clob Blob

Java Byte Array Lob Mapped To Long VarBinary

File: Main.java

   <source lang="java">

import java.util.Collection; 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.setId(1);
   student.setName("Joe");
   student.setPicture("pic".getBytes());
   
   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();
 }

}</source>

Map Serializable Entity To Lob

File: Customer.java

   <source lang="java">

import javax.persistence.*; import java.util.Date; @Entity public class Customer implements java.io.Serializable {

  private int id;
  private JPEG picture;
  
  @Id
  @GeneratedValue
  public int getId()
  {
     return id;
  }
  public void setId(int pk) 
  {
     id = pk;
  }

  @Lob @Basic(fetch=FetchType.LAZY)
  public JPEG getPicture() { return picture; }
  public void setPicture(JPEG jpeg) { picture = jpeg; }

}</source>

Mark Abstract Entity With Mapped Superclass

File: Employee.java

   <source lang="java">

import java.util.Date; import javax.persistence.Column; import javax.persistence.DiscriminatorColumn; import javax.persistence.DiscriminatorValue; import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.Inheritance; import javax.persistence.MappedSuperclass; import javax.persistence.Table; import javax.persistence.Temporal; import javax.persistence.TemporalType; @Entity @Table(name = "EMP") @Inheritance @DiscriminatorColumn(name = "EMP_TYPE") public abstract class Employee {

 @Id
 private int id;
 private String name;
 @Temporal(TemporalType.DATE)
 @Column(name = "S_DATE")
 private Date startDate;
 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 Date getStartDate() {
   return startDate;
 }
 public void setStartDate(Date startDate) {
   this.startDate = startDate;
 }
 public String toString() {
   return "Employee id: " + getId() + " name: " + getName();
 }

} @MappedSuperclass abstract class AbstractEmployee extends Employee {

 private int vacation;
 public int getVacation() {
   return vacation;
 }
 public void setVacation(int vacation) {
   this.vacation = vacation;
 }

} @Entity @DiscriminatorValue("FTEmp") class FullTimeEmployee extends AbstractEmployee {

 private long salary;
 private long pension;
 public long getPension() {
   return pension;
 }
 public void setPension(long pension) {
   this.pension = pension;
 }
 public long getSalary() {
   return salary;
 }
 public void setSalary(long salary) {
   this.salary = salary;
 }
 public String toString() {
   return "FullTimeEmployee id: " + getId() + " name: " + getName();
 }

} @Entity(name = "PTEmp") @DiscriminatorValue("PTEmp") class PartTimeEmployee extends AbstractEmployee {

 @Column(name = "H_RATE")
 private float hourlyRate;
 public float getHourlyRate() {
   return hourlyRate;
 }
 public void setHourlyRate(float hourlyRate) {
   this.hourlyRate = hourlyRate;
 }
 public String toString() {
   return "PartTimeEmployee id: " + getId() + " name: " + getName();
 }

}</source>

Mark Byte Array Field As Lob

File: Student.java

   <source lang="java">

import javax.persistence.Basic; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.FetchType; import javax.persistence.Id; import javax.persistence.Lob; @Entity public class Student {

 @Id
 private int id = 0;
 private String name;
 @Basic(fetch = FetchType.LAZY)
 @Lob
 private byte[] picture;
 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 byte[] getPicture() {
   return picture;
 }
 public void setPicture(byte[] picture) {
   this.picture = picture;
 }
 public String toString() {
   return "\n\nID:" + id + "\nName:" + name + "\n\n";
 }

}</source>

Mark String As Lob

File: Student.java

   <source lang="java">

import javax.persistence.Basic; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.FetchType; import javax.persistence.Id; import javax.persistence.Lob; @Entity public class Student {

 @Id
 private int id = 0;
 @Lob
 private String name;

 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 String toString() {
   return "\n\nID:" + id + "\nName:" + name + "\n\n";
 }

}</source>