package de.vogella.jpa.simple.model;

import lombok.Data;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;

@Entity
@Data
public class Todo {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String summary;
    private String description;
}

package de.vogella.jpa.eclipselink.model;

import java.util.ArrayList;
import java.util.List;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToMany;

@Entity
public class Family {
    @Id
    @GeneratedValue(strategy = GenerationType.TABLE)
    private int id;
    private String description;

    @OneToMany(mappedBy = "family")
    private final List<Person> members = new ArrayList<Person>();

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public List<Person> getMembers() {
        return members;
    }

}

package de.vogella.jpa.eclipselink.model;

import java.util.ArrayList;
import java.util.List;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.OneToMany;
import javax.persistence.Transient;

@Entity
public class Person {
    @Id
    @GeneratedValue(strategy = GenerationType.TABLE)
    private String id;
    private String firstName;
    private String lastName;

    private Family family;

    private String nonsenseField = "";

    private List<Job> jobList = new ArrayList<Job>();

    public String getId() {
        return id;
    }

    public void setId(String Id) {
        this.id = Id;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    // Leave the standard column name of the table
    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    @ManyToOne
    public Family getFamily() {
        return family;
    }

    public void setFamily(Family family) {
        this.family = family;
    }

    @Transient
    public String getNonsenseField() {
        return nonsenseField;
    }

    public void setNonsenseField(String nonsenseField) {
        this.nonsenseField = nonsenseField;
    }

    @OneToMany
    public List<Job> getJobList() {
        return this.jobList;
    }

    public void setJobList(List<Job> nickName) {
        this.jobList = nickName;
    }

}

package de.vogella.jpa.eclipselink.model;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;

@Entity
public class Job {
    @Id
    @GeneratedValue(strategy = GenerationType.TABLE)
    private int id;
    private double salery;
    private String jobDescr;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public double getSalery() {
        return salery;
    }

    public void setSalery(double salery) {
        this.salery = salery;
    }

    public String getJobDescr() {
        return jobDescr;
    }

    public void setJobDescr(String jobDescr) {
        this.jobDescr = jobDescr;
    }

}

<?xml version="1.0" encoding="UTF-8" ?>
<persistence xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
    version="2.0" xmlns="http://java.sun.com/xml/ns/persistence">
    <persistence-unit name="people" transaction-type="RESOURCE_LOCAL">
        
        
        <class>de.vogella.jpa.eclipselink.model.Person</class>
        <class>de.vogella.jpa.eclipselink.model.Family</class>
        <class>de.vogella.jpa.eclipselink.model.Job</class>
        
        <properties>
            <property name="javax.persistence.jdbc.driver" value="org.apache.derby.jdbc.EmbeddedDriver" />
                <property name="javax.persistence.jdbc.url"
                value="jdbc:derby:/home/vogella/databases/relationsshipDb;create=true" />
            <property name="javax.persistence.jdbc.user" value="test" />
            <property name="javax.persistence.jdbc.password" value="test" />

            <!-- EclipseLink should create the database schema automatically -->
            <property name="eclipselink.ddl-generation" value="create-tables" />
            <property name="eclipselink.ddl-generation.output-mode"
                value="database" />
        </properties>

    </persistence-unit>
</persistence>

package de.vogella.jpa.eclipselink.main;

import static org.junit.Assert.assertTrue;

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

import org.junit.Before;
import org.junit.Test;

import de.vogella.jpa.eclipselink.model.Family;
import de.vogella.jpa.eclipselink.model.Person;

public class JpaTest {

    private static final String PERSISTENCE_UNIT_NAME = "people";
    private EntityManagerFactory factory;

    @Before
    public void setUp() throws Exception {
        factory = Persistence.createEntityManagerFactory(PERSISTENCE_UNIT_NAME);
        EntityManager em = factory.createEntityManager();

        // Begin a new local transaction so that we can persist a new entity
        em.getTransaction().begin();

        // read the existing entries
        Query q = em.createQuery("select m from Person m");
        // Persons should be empty

        // do we have entries?
        boolean createNewEntries = (q.getResultList().size() == 0);

        // No, so lets create new entries
        if (createNewEntries) {
            assertTrue(q.getResultList().size() == 0);
            Family family = new Family();
            family.setDescription("Family for the Knopfs");
            em.persist(family);
            for (int i = 0; i < 40; i++) {
                Person person = new Person();
                person.setFirstName("Jim_" + i);
                person.setLastName("Knopf_" + i);
                em.persist(person);
                // now persists the family person relationship
                family.getMembers().add(person);
                em.persist(person);
                em.persist(family);
            }
        }

        // Commit the transaction, which will cause the entity to
        // be stored in the database
        em.getTransaction().commit();

        // It is always good practice to close the EntityManager so that
        // resources are conserved.
        em.close();

    }

    @Test
    public void checkAvailablePeople() {

        // now lets check the database and see if the created entries are there
        // create a fresh, new EntityManager
        EntityManager em = factory.createEntityManager();

        // Perform a simple query for all the Message entities
        Query q = em.createQuery("select m from Person m");

        // We should have 40 Persons in the database
        assertTrue(q.getResultList().size() == 40);

        em.close();
    }

    @Test
    public void checkFamily() {
        EntityManager em = factory.createEntityManager();
        // Go through each of the entities and print out each of their
        // messages, as well as the date on which it was created
        Query q = em.createQuery("select f from Family f");

        // We should have one family with 40 persons
        assertTrue(q.getResultList().size() == 1);
        assertTrue(((Family) q.getSingleResult()).getMembers().size() == 40);
        em.close();
    }

    @Test(expected = javax.persistence.NoResultException.class)
    public void deletePerson() {
        EntityManager em = factory.createEntityManager();
        // Begin a new local transaction so that we can persist a new entity
        em.getTransaction().begin();
        Query q = em
                .createQuery("SELECT p FROM Person p WHERE p.firstName = :firstName AND p.lastName = :lastName");
        q.setParameter("firstName", "Jim_1");
        q.setParameter("lastName", "Knopf_!");
        Person user = (Person) q.getSingleResult();
        em.remove(user);
        em.getTransaction().commit();
        Person person = (Person) q.getSingleResult();
        // Begin a new local transaction so that we can persist a new entity

        em.close();
    }
}