JPA Abs Function

In this section, you will learn about the JPA Abs() function. This method returns absolute value of the given field.

JPA Abs Function

JPA Abs Function

     

In this section, you will learn about the JPA Abs() function. This method returns absolute value of the given field.

JPA Abs Function:

Query query=em.createQuery("SELECT p FROM Product p WHERE ABS(p.price)<50.0");

This query retrieve all products which have the price less than "50".

For JPA abs application, you need the following artifacts:

  1. Database Table: product
  2. Model Class: Product.java
  3. Main Class: JPAAbsFunction.java

Database Table: product

CREATE TABLE `product` ( 
`id` int(11) NOT NULL auto_increment, 
`itemName` varchar(50) NOT NULL, 
`price` double NOT NULL, 
PRIMARY KEY (`id`) 
)

Model Class: Product.java

/**

*/
package roseindia;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;

/**
* @author Administrator
*
*/
@Entity
@Table(name="product")
public class Product {

@Id
@GeneratedValue
private int id;
/**
* @return the id
*/
public int getId() {
return id;
}

/**
* @param id the id to set
*/
public void setId(int id) {
this.id = id;
}

@Column(name="itemName",length=50,nullable=false)
private String itemName;
/**
* @return the itemName
*/
public String getItemName() {
return itemName;
}

/**
* @param itemName the itemName to set
*/
public void setItemName(String itemName) {
this.itemName = itemName;
}

@Column(name="price")
private double price;
/**
* @return the price
*/
public double getPrice() {
return price;
}

/**
* @param price the price to set
*/
public void setPrice(double price) {
this.price = price;
}

}

Main Class: JPAAbsFunction.java

/**

*/
package roseindia;

import java.util.Iterator;
import java.util.List;

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.EntityTransaction;
import javax.persistence.Persistence;
import javax.persistence.Query;

/**
* @author Administrator
*
*/
public class JPAAbsFunction {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub

EntityManagerFactory emf=Persistence.createEntityManagerFactory("jpa");
EntityManager em=emf.createEntityManager();
try{
EntityTransaction entr=em.getTransaction();
entr.begin();
Query query=em.createQuery("SELECT p FROM Product p WHERE ABS(p.price)<50.0");
List pList=query.getResultList();
Iterator pIterator=pList.iterator();
while(pIterator.hasNext()){
Product pro=(Product)pIterator.next();
System.out.println("itemName:"+pro.getItemName());
}
entr.commit();
}
finally{
em.close();
}

}

}

Output:

log4j:WARN No appenders could be found for logger (org.hibernate.cfg.annotations.Version).

log4j:WARN Please initialize the log4j system properly.

Hibernate: select product0_.id as id1_, product0_.itemName as itemName1_, product0_.price as price1_ from product product0_ where abs(product0_.price)<50.0

itemName:Dall

itemName:Chock

 

Product table records: