craigew

package com.craigew.service;


import com.craigew.entity.Address;
import com.craigew.entity.Customer;
import junit.framework.Assert;
import org.junit.Test;

import javax.persistence.EntityNotFoundException;
import java.util.List;

craigew

    public List<Customer> returnAllCustomers() {
        return queryString("SELECT e FROM Customer e");
    }

    public List<Customer> returnCustomersForACountry(String country) {
        return queryString("SELECT e FROM Customer e WHERE e.residentialAddress.country='" + country + "'");
    }

craigew

protected List<T> queryString(String sql){
        EntityManagerFactory factory = Persistence.createEntityManagerFactory("JPAIntroduction");
        EntityManager em = factory.createEntityManager();
        List<T> results= em.createQuery(sql).getResultList();
        em.close();
        factory.close();
        return results;
    }

craigew

@OneToOne(cascade = CascadeType.ALL, optional=false)
    @JoinColumn(name="RESIDENTIAL_ADDRESS_ID")
    private Address residentialAddress;
    @OneToOne(cascade = CascadeType.ALL, optional=true)
    @JoinColumn(name="POSTAL_ADDRESS_ID")
    private Address postalAddress;

craigew

<class>com.craigew.entity.Address</class>

craigew

package com.craigew.entity;

import javax.persistence.Entity;

@Entity
public class Address extends BaseEntity{
    private String addressLine1;
    private String addressLine2;
    private String suburb;
    private String postalCode;

craigew

public class CustomerManagementService extends DataAccess<Customer> {

    public long createCustomer(Customer customer) {
        return add(customer);
    }

    public boolean updateCustomer(Customer customer) {
        update(customer);
        return true;
    }

craigew

public class DataAccess<T extends BaseEntity> {
    private Class<T> entityClass;

    protected long add(T object){
        EntityManagerFactory factory = Persistence.createEntityManagerFactory("JPAIntroduction");
        EntityManager em = factory.createEntityManager();
        em.getTransaction().begin();
        em.persist(object);
        em.getTransaction().commit();
        long id=object.getId();

craigew

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
             version="1.0">
    <persistence-unit name="JPAIntroduction" transaction-type="RESOURCE_LOCAL">
        <provider>org.apache.openjpa.persistence.PersistenceProviderImpl</provider>
        <class>com.craigew.entity.Customer</class>
        <class>com.craigew.entity.BaseEntity</class>
        <properties>
            <property name="openjpa.ConnectionURL" value="jdbc:oracle:thin:@192.168.0.9:1521/xe"/>
            <property name="openjpa.ConnectionDriverName" value="oracle.jdbc.driver.OracleDriver"/>
            <property name="openjpa.ConnectionUserName" value="dev"/>

craigew

@MappedSuperclass
public class BaseEntity implements Identifier{

    @Id
    @GeneratedValue(strategy= GenerationType.SEQUENCE, generator="id_sequence_gen")
    @SequenceGenerator(name="id_sequence_gen", sequenceName="id_sequence")
    private long id;


    public long getId() {