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2010-06-01T05:18:32Z

1 версия

в 17:44, 31 мая 2010

2010-05-31T17:44:27Z

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== 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>

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Admin: 1 версия

в 17:44, 31 мая 2010