Hibernate ScrollableResults and ScrollMode Example
November 29, 2015
ScrollableResults
org.hibernate.ScrollableResults scrolls results by the given increments. The columns of the results start from zero. Find some methods ofScrollableResults.
scroll(int i) : Scrolls the results. i represents the number for forward or backward scrolling.
setRowNumber(int rowNumber) : It sets the current location in
ScrollableResults.
get(int i) : Gets the object at index i in current row.
get() : It returns the array of
Object of current row.s
afterLast() : It sets the location just after the last result.
beforeFirst() : It sets the location just before the first result.
ScrollMode
org.hibernate.ScrollMode is anEnum which provides the different mode to fetch ScrollableResults.
FORWARD_ONLY : It requests
ScrollableResults that scrolls forward only.
SCROLL_SENSITIVE :
ScrollableResults that is sensitive to changes in underlying data.
SCROLL_INSENSITIVE : Insensitive to changes in underlying data.
Data used in Example
build.gradle
apply plugin: 'java'
apply plugin: 'eclipse'
archivesBaseName = 'hibernate-4'
version = '1'
repositories {
mavenCentral()
}
dependencies {
compile 'org.hibernate:hibernate-core:4.3.8.Final'
compile 'mysql:mysql-connector-java:5.1.34'
}
Hibernate Utility and Entity Class
HibernateUtil.java
package com.concretepage;
import org.hibernate.SessionFactory;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
public class HibernateUtil {
private static SessionFactory sessionFactory ;
static {
Configuration configuration = new Configuration().configure();
StandardServiceRegistryBuilder builder = new StandardServiceRegistryBuilder()
.applySettings(configuration.getProperties());
sessionFactory = configuration.buildSessionFactory(builder.build());
}
public static SessionFactory getSessionFactory() {
return sessionFactory;
}
}
Student.java
package com.concretepage;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;
@Entity
@Table(name="student")
public class Student {
@Id
@Column(name="id")
private int id;
@Column(name="name")
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;
}
}
Scroll Results with Session.createCriteria()
ScrollableResultsWithCriteria.java
package com.concretepage;
import org.hibernate.ScrollMode;
import org.hibernate.ScrollableResults;
import org.hibernate.Session;
public class ScrollableResultsWithCriteria {
public static void main(String[] args) {
Session session = HibernateUtil.getSessionFactory().openSession();
ScrollableResults scResults = session.createCriteria(Student.class)
.scroll(ScrollMode.FORWARD_ONLY);
while(scResults.next()) {
Student s = (Student)scResults.get(0);
System.out.println(s.getId()+", "+s.getName());
}
//Set the location at index 2
System.out.println("After setting location");
scResults.setRowNumber(1);
while(scResults.next()) {
Student s = (Student)scResults.get(0);
System.out.println(s.getId()+", "+s.getName());
}
session.close();
}
}
Hibernate: select this_.id as id1_0_0_, this_.name as name2_0_0_ from student this_ 1, AA 2, BB 3, CC After setting location 3, CC
Scroll Results with Session.createQuery()
ScrollableResultsWithQuery.java
package com.concretepage;
import org.hibernate.ScrollMode;
import org.hibernate.ScrollableResults;
import org.hibernate.Session;
public class ScrollableResultsWithQuery {
public static void main(String[] args) {
Session session = HibernateUtil.getSessionFactory().openSession();
ScrollableResults scResults = session.createQuery("from Student")
.scroll(ScrollMode.SCROLL_INSENSITIVE);
while(scResults.next()) {
Student s = (Student)scResults.get(0);
System.out.println(s.getId()+", "+s.getName());
scResults.afterLast();
}
session.close();
}
}
Hibernate: select student0_.id as id1_0_, student0_.name as name2_0_ from student student0_ 1, AA
Scroll Results with Session.createSQLQuery()
ScrollableResultsWithSQLQuery.java
package com.concretepage;
import org.hibernate.ScrollMode;
import org.hibernate.ScrollableResults;
import org.hibernate.Session;
public class ScrollableResultsWithSQLQuery {
public static void main(String[] args) {
Session session = HibernateUtil.getSessionFactory().openSession();
ScrollableResults scResults = session.createSQLQuery("SELECT id, name FROM student")
.scroll(ScrollMode.SCROLL_SENSITIVE);
while(scResults.next()) {
Object[] row = scResults.get();
System.out.println(row[0]+", "+ row[1]);
}
session.close();
}
}
Hibernate: SELECT id, name FROM student 1, AA 2, BB 3, CC
