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JPA Source codes

==================[ 1-JavaApp1.java ]====================
import java.util.*;
import javax.persistence.*;
public class JavaApp1{
public static void main(String ar[]){
EntityManagerFactory emf=Persistence.createEntityManagerFactory("persistunit");
EntityManager em=emf.createEntityManager();
EntityTransaction tx=em.getTransaction();
Scanner scan=new Scanner(System.in);
String q="";
while(!q.equals("y")){
pack.Student student=new pack.Student();
System.out.println("Enter id, name, course");
int id=scan.nextInt();
String name=scan.next();
String course=scan.next();

student.setId(id);
student.setName(name);
student.setCourse(course);

tx.begin();
em.persist(student);
tx.commit();
System.out.println("Press y to exit");
q=scan.next();
}
}
}
==================[ 2-Student.java ]====================
package pack;
import javax.persistence.*;

@Enti
public class Student{
private int id;
private String name;
private String course;

@Id
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 getCourse()
{
return course;
}
public void setCourse(String course)
{
this.course=course;
}
}

==================[ 3-JavaApp1.java ]====================
import java.util.*;
import javax.persistence.*;
public class JavaApp1{
public static void main(String ar[]){
EntityManagerFactory emf=Persistence.createEntityManagerFactory("persistunit");
EntityManager em=emf.createEntityManager();
EntityTransaction tx=em.getTransaction();
pack.Student s=em.find(pack.Student.class,3);
System.out.println(s.getId()+"\t"+s.getName()+"\t"+s.getCourse());

s.setName("Pankaj");

tx.begin();
//em.merge(s);
em.remove(s);
tx.commit();
// System.out.println("Press y to exit");
// q=scan.next();

}
}
==================[ 4-JavaApp1.java ]====================
import java.util.*;
import javax.persistence.*;
public class JavaApp1{
public static void main(String ar[]){
EntityManagerFactory emf=Persistence.createEntityManagerFactory("persistunit");
EntityManager em=emf.createEntityManager();
Query q=em.createQuery("SELECT OBJECT(st) FROM Student st");

List<pack.Student> rl=q.getResultList();
for(pack.Student s:rl){
System.out.println(s.getId()+"\t"+s.getName()+"\t"+s.getCourse());
}

}
}
==================[ 5-JavaApp1.java ]====================
import java.util.*;
import javax.persistence.*;
public class JavaApp1{
public static void main(String ar[]){
EntityManagerFactory emf=Persistence.createEntityManagerFactory("persistunit");
EntityManager em=emf.createEntityManager();
Query q=em.createQuery("UPDATE Student st set st.course='j2ee' where st.id=2");
EntityTransaction tx=em.getTransaction();
tx.begin();
q.executeUpdate();
tx.commit();
}
}
==================[ 6-JavaApp1.java ]====================
import java.util.*;
import javax.persistence.*;
public class JavaApp1{
public static void main(String ar[]){
EntityManagerFactory emf=Persistence.createEntityManagerFactory("persistunit");
EntityManager em=emf.createEntityManager();
Query q=em.createQuery("DELETE FROM Student st where st.id=2");
EntityTransaction tx=em.getTransaction();
tx.begin();
q.executeUpdate();
tx.commit();
}
}
==================[ 7-Course.java ]====================
package pack;
import javax.persistence.*;

@Entity
public class Course{
private int id;
private String name;

@Id
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;
}
}

==================[ 8-JavaApp1.java ]====================
import java.util.*;
import javax.persistence.*;
public class JavaApp1{
public static void main(String ar[]){
EntityManagerFactory emf=Persistence.createEntityManagerFactory("persistunit");
EntityManager em=emf.createEntityManager();
EntityTransaction tx=em.getTransaction();

pack.Student st=new pack.Student();
pack.Course c=new pack.Course();
st.setId(2);
st.setName("abc");
c.setId(2);
c.setName("MCA");

ArrayList al=new ArrayList();
al.add(c);
st.setCourse(al);
tx.begin();
//em.persist(c);
em.persist(st);
tx.commit();
}
}
==================[ 9-Student.java ]====================
package pack;
import javax.persistence.*;
import java.util.*;
@Entity
public class Student{
private int id;
private String name;
private Collection <Course> course;

@Id
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;
}
@OneToOne(cascade={CascadeType.ALL})
public Collection <Course> getCourse()
{
return course;
}
public void setCourse(Collection <Course> course)
{
this.course=course;
}
}

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