JPA 2.0(JavaEE 6 by GlassFish 3.1) Example with CriteriaQuery.

JPAExample.java

import java.util.List;
import javax.ejb.embeddable.EJBContainer;
import javax.naming.NamingException;
import javax.persistence.EntityManager;
import javax.persistence.Persistence;
import javax.persistence.Query;
import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.Predicate;
import javax.persistence.criteria.Root;
import model.Customer;

/*
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 * and open the template in the editor.
 */

/**
 *
 * @author hiro
 */
public class JPAExample {

    public static void main(String[] args) throws NamingException {
        EJBContainer container = EJBContainer.createEJBContainer();
        
        // persistance.xmlの読み込み.
        EntityManager em = Persistence.createEntityManagerFactory("CustomerDBPU").createEntityManager();

        // CriteriaQuery
        System.out.println("CriteriaQueryによる検索.");
        CriteriaBuilder builder = em.getCriteriaBuilder();
        CriteriaBuilder cb = em.getCriteriaBuilder();
        CriteriaQuery<Customer> cq = cb.createQuery(Customer.class);
        Root<Customer> customer = cq.from(Customer.class);
        Predicate predicate = cb.equal(customer.get("customerId"), 409);
        for (Customer c : em.createQuery(cq.select(customer).where(predicate)).getResultList()) {
            System.out.println("customer is " + c.getName());
        }
        
        // Count
        System.out.println("CriteriaQueryによるcount.");
        CriteriaQuery<Long> cq2 = builder.createQuery(Long.class);
        cq2.select(builder.count(customer));
        System.out.println(em.createQuery(cq2.where(predicate)).getSingleResult());
        
        // JPQL
        System.out.println("JPQLによる検索.");
        Query query = em.createNamedQuery("Customer.findByCustomerId");
        query.setParameter("customerId", 410);
        List<Customer> list = query.getResultList();
        for(Customer c : list){
            System.out.println("customer is " + c.getName());
        }


        container.close();
    }
    
}

persistance.xml

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.0" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
  <persistence-unit name="CustomerDBPU" transaction-type="JTA">
    <jta-data-source>jdbc/sample</jta-data-source>
    <exclude-unlisted-classes>false</exclude-unlisted-classes>
    <properties>
        <property name="eclipselink.logging.level" value="FINE" />
        <property name="eclipselink.logging.timestamp" value="true" />
        <property name="eclipselink.logging.session" value="true" />
        <property name="eclipselink.logging.thread" value="true" />
    </properties>
  </persistence-unit>
</persistence>