<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence" version="2.0">

    <persistence-unit name="NewPersistenceUnit">
        <provider>org.hibernate.ejb.HibernatePersistence</provider>
        <class>Hello.Customer</class>
        <properties>
            <!-- 连接数据库的基本信息 -->
            <property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver"/>
            <property name="javax.persistence.jdbc.url" value="jdbc:mysql:///test"/>
            <property name="javax.persistence.jdbc.user" value="root"/>
            <property name="javax.persistence.jdbc.password" value="root"/>

            <!-- 配置 JPA 实现产品的基本属性. 配置 hibernate 的基本属性 -->
            <property name="hibernate.format_sql" value="true"/>
            <property name="hibernate.show_sql" value="true"/>
            <property name="hibernate.hbm2ddl.auto" value="update"/>

            <!-- 二级缓存相关 -->
            <property name="hibernate.cache.use_second_level_cache" value="true"/>
            <property name="hibernate.cache.region.factory_class" value="org.hibernate.cache.ehcache.EhCacheRegionFactory"/>
            <property name="hibernate.cache.use_query_cache" value="true"/>
        </properties>
    </persistence-unit>
</persistence>

package Hello;

import javax.persistence.*;

@NamedQuery(name="testNamedQuery", query="FROM Customer c WHERE c.id = ?")
@Cacheable(true)
@Table(name="JPA_CUTOMERS")
@Entity
public class Customer {

    private Integer id;
    private String lastName;

    private String email;
    private int age;


    public Customer() {
        // TODO Auto-generated constructor stub
    }
    
    public Customer(String lastName, int age) {
        super();
        this.lastName = lastName;
        this.age = age;
    }


    @GeneratedValue(strategy= GenerationType.AUTO)
    @Id
    public Integer getId() {
        return id;
    }

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

    @Column(name="LAST_NAME",length=50,nullable=false)
    public String getLastName() {
        return lastName;
    }

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

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }
    


    @Override
    public String toString() {
        return "Hello.Customer [id=" + id + ", lastName=" + lastName + ", email="
                + email + ", age=" + age +  "]";
    }

}

package Hello;

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.EntityTransaction;
import javax.persistence.Persistence;
import java.util.HashMap;
import java.util.Map;

public class Main {

    public static void main(String[] args) {

        //1. 创建 EntitymanagerFactory
        String persistenceUnitName = "NewPersistenceUnit";

        Map<String, Object> properites = new HashMap<String, Object>();
        properites.put("hibernate.show_sql", true);

        EntityManagerFactory entityManagerFactory =
                //Persistence.createEntityManagerFactory(persistenceUnitName);
                Persistence.createEntityManagerFactory(persistenceUnitName, properites);

        //2. 创建 EntityManager. 类似于 Hibernate 的 SessionFactory
        EntityManager entityManager = entityManagerFactory.createEntityManager();

        //3. 开启事务
        EntityTransaction transaction = entityManager.getTransaction();
        transaction.begin();

        //4. 进行持久化操作
        Customer customer = new Customer();
        customer.setAge(12);
        customer.setEmail("god@god.com");
        customer.setLastName("Tom");


        entityManager.persist(customer);

        //5. 提交事务
        transaction.commit();

        //6. 关闭 EntityManager
        entityManager.close();

        //7. 关闭 EntityManagerFactory
        entityManagerFactory.close();
    }

}