[[collections-customizing-ordered-list-ordinal]]

===== Customizing ordered list ordinal

You can customize the ordinal of the underlying ordered list by using the https://docs.jboss.org/hibernate/orm/{majorMinorVersion}/javadocs/org/hibernate/annotations/ListIndexBase.html[`@ListIndexBase`] annotation.

[[collections-customizing-ordered-list-ordinal-mapping-example]]

.`@ListIndexBase` mapping example

When inserting two `Phone` records, Hibernate is going to start the List index from 100 this time.

[[collections-customizing-ordered-list-ordinal-persist-example]]

.`@ListIndexBase` persist example

INSERT INTO Phone("number", person_id, type, id)

VALUES ('028-234-9876', 1, 'landline', 1)

INSERT INTO Phone("number", person_id, type, id)

VALUES ('072-122-9876', 1, 'mobile', 2)

UPDATE Phone

SET order_id = 100

WHERE id = 1

UPDATE Phone

SET order_id = 101

WHERE id = 2

package org.hibernate.userguide.collections;

import java.util.ArrayList;

import java.util.List;

import java.util.Objects;

import javax.persistence.CascadeType;

import javax.persistence.Column;

import javax.persistence.Entity;

import javax.persistence.Id;

import javax.persistence.ManyToOne;

import javax.persistence.OneToMany;

import javax.persistence.OrderColumn;

import org.hibernate.annotations.ListIndexBase;

import org.hibernate.annotations.NaturalId;

import org.hibernate.jpa.test.BaseEntityManagerFunctionalTestCase;

import org.junit.Test;

import static org.hibernate.testing.transaction.TransactionUtil.doInJPA;

public class OrderColumnListIndexBaseTest extends BaseEntityManagerFunctionalTestCase {

@Override

protected Class<?>[] getAnnotatedClasses() {

return new Class<?>[] {

Person.class,

Phone.class,

};

}

@Test

public void testLifecycle() {

doInJPA( this::entityManagerFactory, entityManager -> {

//tag::collections-customizing-ordered-list-ordinal-persist-example[]

Person person = new Person( 1L );

entityManager.persist( person );

person.addPhone( new Phone( 1L, "landline", "028-234-9876" ) );

person.addPhone( new Phone( 2L, "mobile", "072-122-9876" ) );

//end::collections-customizing-ordered-list-ordinal-persist-example[]

} );

}

@Entity(name = "Person")

public static class Person {

@Id

private Long id;

//tag::collections-customizing-ordered-list-ordinal-mapping-example[]

@OneToMany(mappedBy = "person", cascade = CascadeType.ALL)

@OrderColumn(name = "order_id")

@ListIndexBase(100)

private List<Phone> phones = new ArrayList<>();

//end::collections-customizing-ordered-list-ordinal-mapping-example[]

public Person() {

}

public Person(Long id) {

this.id = id;

}

public List<Phone> getPhones() {

return phones;

}

public void addPhone(Phone phone) {

phones.add( phone );

phone.setPerson( this );

}

public void removePhone(Phone phone) {

phones.remove( phone );

phone.setPerson( null );

}

}

@Entity(name = "Phone")

public static class Phone {

@Id

private Long id;

private String type;

@Column(name = "`number`", unique = true)

@NaturalId

private String number;

@ManyToOne

private Person person;

public Phone() {

}

public Phone(Long id, String type, String number) {

this.id = id;

this.type = type;

this.number = number;

}

public Long getId() {

return id;

}

public String getType() {

return type;

}

public String getNumber() {

return number;

}

public Person getPerson() {

return person;

}

public void setPerson(Person person) {

this.person = person;

}

@Override

public boolean equals(Object o) {

if ( this == o ) {

return true;

}

if ( o == null || getClass() != o.getClass() ) {

return false;

}

Phone phone = (Phone) o;

return Objects.equals( number, phone.number );

}

@Override

public int hashCode() {

return Objects.hash( number );

}

}

}