Tutorial_2_The_First_Example

Test Setup

We have a bit of setup/initialization code we need to do before we can get started. We have seen all of this code before in Tutorial 1. The difference here is that we are going to work though some refactorings to get to where we were in tutorial 1. Here are the various parts:

Configure the Logger

    BasicConfigurator.configure();
    Logger.getLogger("org").setLevel(Level.ERROR);

Create the Entity Manager Factory

    final EntityManagerFactory emf = Persistence
        .createEntityManagerFactory("examplePersistenceUnit");

Create the Entity Manager

    final EntityManager em = emf.createEntityManager();

Create Entities

    final Address a1 = new Address("A Rd.", "", "Dallas", "TX", "75001");
    final Person p1 = new Person("Brett", 'L', "Schuchert", a1);

    final Address a2 = new Address("B Rd.", "S2", "OkC", "OK", "73116");
    final Person p2 = new Person("FirstName" + System.currentTimeMillis(),
        'K', "LastName", a2);

Use the Entity Manager

    em.getTransaction().begin();
    em.persist(p1);
    em.persist(p2);
    em.flush();

Perform a Query and Verify it Works

    final int numberFound = em.createQuery("Select p from Person p")
        .getResultList().size();
    assertEquals(2, numberFound);

The Whole Thing

Here’s all of this put together. Note that we’re going to refactor this heavily coming up.

package entity;

import static org.junit.Assert.assertEquals;

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

import org.apache.log4j.BasicConfigurator;
import org.apache.log4j.Level;
import org.apache.log4j.Logger;
import org.junit.Test;

public class JpaApiTests {

    @Test
    public void example1InsertTwoPeople() {
        BasicConfigurator.configure();
        Logger.getLogger("org").setLevel(Level.ERROR);

        final EntityManagerFactory emf = Persistence
                .createEntityManagerFactory("examplePersistenceUnit");
        final EntityManager em = emf.createEntityManager();

        final Address a1 = new Address("A Rd.", "", "Dallas", "TX", "75001");
        final Person p1 = new Person("Brett", 'L', "Schuchert", a1);

        final Address a2 = new Address("B Rd.", "S2", "OkC", "OK", "73116");
        final Person p2 = new Person("FirstName" + System.currentTimeMillis(),
                'K', "LastName", a2);

        em.getTransaction().begin();
        em.persist(p1);
        em.persist(p2);
        em.flush();

        final int numberFound = em.createQuery("Select p from Person p")
                .getResultList().size();
        assertEquals(2, numberFound);
    }
}

Get it Running

After creating your Test Class, verify that it runs and that this test passes:

Right-click anywhere in your class’ editor pane.
Select Run As:JUnit Test