笔记来源：尚硅谷jpa开发教程全套完整版(初学者零基础入门)

Spring 整合 JPA

1、三种整合方式

1）LocalEntityManagerFactoryBean：适用于那些仅使用 JPA 进行数据访问的项目，该 FactoryBean 将根据 JPAPersistenceProvider 自动检测配置文件进行工作，一般从 ”META-INF/persistence.xml“ 读取配置信息，这种方式最简单，但不能设置 Spring 中定义的 DataSource，且不支持 Spring 管理的全局事务
2）从 JNDI 中获取：用于从 JavaEE 服务器获取指定的 EntityManagerFactory，这种方式在进行 Spring 事务管理时一般要使用 JTA 事务管理
3）LocalContainerEntityManagerFactoryBean：适用于所有环境的 FactoryBean，能全面控制 EntityManagerFactory 配置，如指定 Spring 定义的 DataSource 等等

综上所述，第三种整合方式最优

2、pom 依赖

依赖 jar 包清单：

Hibernate 相关
JPA 相关
c3p0 相关
MySQL 驱动相关
Spring 相关

<properties>
    <maven.compiler.source>8</maven.compiler.source>
    <maven.compiler.target>8</maven.compiler.target>
    <spring.version>4.0.0.RELEASE</spring.version>
</properties>

<dependencies>
    <!-- Hibernate 相关 -->
    <dependency>
        <groupId>antlr</groupId>
        <artifactId>antlr</artifactId>
        <version>2.7.7</version>
    </dependency>
    <dependency>
        <groupId>dom4j</groupId>
        <artifactId>dom4j</artifactId>
        <version>1.6.1</version>
    </dependency>
    <dependency>
        <groupId>org.hibernate.common</groupId>
        <artifactId>hibernate-commons-annotations</artifactId>
        <version>4.0.2.Final</version>
    </dependency>
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-core</artifactId>
        <version>4.2.4.Final</version>
    </dependency>
    <dependency>
        <groupId>org.javassist</groupId>
        <artifactId>javassist</artifactId>
        <version>3.15.0-GA</version>
    </dependency>
    <dependency>
        <groupId>org.jboss.logging</groupId>
        <artifactId>jboss-logging</artifactId>
        <version>3.1.0.GA</version>
    </dependency>
    <dependency>
        <groupId>org.jboss.spec.javax.transaction</groupId>
        <artifactId>jboss-transaction-api_1.1_spec</artifactId>
        <version>1.0.1.Final</version>
    </dependency>
    <!-- JPA 相关 -->
    <dependency>
        <groupId>org.hibernate.javax.persistence</groupId>
        <artifactId>hibernate-jpa-2.0-api</artifactId>
        <version>1.0.1.Final</version>
    </dependency>
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-entitymanager</artifactId>
        <version>4.2.4.Final</version>
    </dependency>
    <!-- c3p0 相关 -->
    <dependency>
        <groupId>com.mchange</groupId>
        <artifactId>c3p0</artifactId>
        <version>0.9.2.1</version>
    </dependency>
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-c3p0</artifactId>
        <version>4.2.4.Final</version>
    </dependency>
    <dependency>
        <groupId>com.mchange</groupId>
        <artifactId>mchange-commons-java</artifactId>
        <version>0.2.3.4</version>
    </dependency>
    <!-- MySQL 相关 -->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.28</version>
    </dependency>
    <!-- Spring 相关 -->
    <dependency>
        <groupId>net.sourceforge.cglib</groupId>
        <artifactId>com.springsource.net.sf.cglib</artifactId>
        <version>2.2.0</version>
    </dependency>
    <dependency>
        <groupId>org.aopalliance</groupId>
        <artifactId>com.springsource.org.aopalliance</artifactId>
        <version>1.0.0</version>
    </dependency>
    <dependency>
        <groupId>org.aspectj</groupId>
        <artifactId>com.springsource.org.aspectj.weaver</artifactId>
        <version>1.6.4.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>commons-logging</groupId>
        <artifactId>commons-logging</artifactId>
        <version>1.1.3</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-aop</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-aspects</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-beans</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-core</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-expression</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-orm</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-tx</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-web</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <!-- junit 相关 -->
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.13.2</version>
        <scope>test</scope>
    </dependency>
</dependencies>

3、jdbc 配置

resources 目录下新建文件 db.properties，配置信息如下

jdbc.user=root
jdbc.password=root
jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.jdbcUrl=jdbc:mysql:///jpa

4、Spring 配置

resources 目录下新建文件 applicationContext.xml，配置清单如下

自动扫描包
c3p0 数据源
DataSource
EntityManagerFactory
事务管理器
基于注解的事务

配置信息如下

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
            http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
            http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd">
    <!--配置自动扫描的包-->
    <context:component-scan base-package="com.vectorx.jpa_spring"></context:component-scan>
    <!--配置 c3p0 数据源-->
    <context:property-placeholder location="classpath:db.properties"/>
    <!--配置 DataSource-->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="user" value="${jdbc.user}"></property>
        <property name="password" value="${jdbc.password}"></property>
        <property name="driverClass" value="${jdbc.driverClass}"></property>
        <property name="jdbcUrl" value="${jdbc.jdbcUrl}"></property>
    </bean>
    <!--配置 EntityManagerFactory-->
    <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <!--配置 DataSource-->
        <property name="dataSource" ref="dataSource"></property>
        <!--配置 JPA 提供商适配器-->
        <property name="jpaVendorAdapter">
            <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"></bean>
        </property>
        <!--配置实体类所在的包-->
        <property name="packagesToScan" value="com.vectorx.jpa_spring.entities"></property>
        <!--配置 JPA 基本属性-->
        <property name="jpaProperties">
            <props>
                <prop key="hibernate.show_sql">true</prop>
                <prop key="hibernate.format_sql">true</prop>
                <prop key="hibernate.hbm2ddl.auto">update</prop>
            </props>
        </property>
    </bean>
    <!--配置 JPA 的事务管理器-->
    <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
        <!--配置 EntityManagerFactory-->
        <property name="entityManagerFactory" ref="entityManagerFactory"></property>
    </bean>
    <!--配置支持基于注解的事务-->
    <tx:annotation-driven transaction-manager="transactionManager"/>
</beans>

5、HelloWorld

准备工作

Person 实体类

@Table(name = "JPA_PERSONS")
@Entity
public class Person
{
    private Integer id;
    private String lastName;
    private String email;
    private int age;

    @GeneratedValue
    @Id
    public Integer getId() {
        return id;
    }

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

    @Column(name = "LAST_NAME")
    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;
    }
}

PersonDao 类

@Repository
public class PersonDao
{
    @PersistenceContext
    private EntityManager entityManager;

    public void save(Person p){
        entityManager.persist(p);
    }
}

PersonService 类

@Service
public class PersonService
{
    @Autowired
    private PersonDao personDao;

    @Transactional
    public void savePerson(Person p1, Person p2) {
        personDao.save(p1);
        personDao.save(p2);
    }
}

初始化表

public class JPATest
{
    private ApplicationContext context;
    {
        context = new ClassPathXmlApplicationContext("applicationContext.xml");
    }

    @Test
    public void testDataSource() throws SQLException {
        DataSource dataSource = context.getBean(DataSource.class);
        System.out.println(dataSource.getConnection());
    }
}

执行 testDataSource 测试方法，查看日志信息，能够打印出连接对象信息，说明 DataSource 数据源配置正常

com.mchange.v2.c3p0.impl.NewProxyConnection@71104a4

查看 JPA_PERSONS 数据表结构也正常生成

测试保存

public class JPATest
{
    private ApplicationContext context;
    private PersonService personService;
    {
        context = new ClassPathXmlApplicationContext("applicationContext.xml");
        personService = context.getBean(PersonService.class);
    }

    @Test
    public void testPersonService(){
        Person p1 = new Person();
        p1.setLastName("AA");
        p1.setAge(11);
        p1.setEmail("AA@qq.com");
        Person p2 = new Person();
        p2.setLastName("BB");
        p2.setAge(22);
        p2.setEmail("BB@qq.com");

        System.out.println(personService.getClass().getName());
        personService.savePerson(p1, p2);
    }
}

日志信息

com.vectorx.jpa_spring.service.PersonService$$EnhancerByCGLIB$$2e5519cd
Hibernate: 
    insert 
    into
        JPA_PERSONS
        (age, email, LAST_NAME) 
    values
        (?, ?, ?)
Hibernate: 
    insert 
    into
        JPA_PERSONS
        (age, email, LAST_NAME) 
    values
        (?, ?, ?)

数据表 JPA_PERSONS 数据

修改 PersonService 的 savePerson 方法，模拟异常的发生

personDao.save(p1);
// 模拟异常
int i = 10 / 0;
personDao.save(p2);

再次执行测试类方法，查看日志信息

com.vectorx.jpa_spring.service.PersonService$$EnhancerByCGLIB$$cab2539e
Hibernate: 
    insert 
    into
        JPA_PERSONS
        (age, email, LAST_NAME) 
    values
        (?, ?, ?)

java.lang.ArithmeticException: / by zero

	at com.vectorx.jpa_spring.service.PersonService.savePerson(PersonService.java:26)
	at com.vectorx.jpa_spring.service.PersonService$$FastClassByCGLIB$$5fe473d0.invoke(<generated>)
	at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
	at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:713)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
	at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:98)
	at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:262)
	at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:95)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
	at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:646)
	at com.vectorx.jpa_spring.service.PersonService$$EnhancerByCGLIB$$cab2539e.savePerson(<generated>)
	at com.vectorx.jpa_spring.JPATest.testPersonService(JPATest.java:46) <25 internal lines>

说明事务生效，符合预期

【SpringData&JPA从入门到精通】05-Spring 整合 JPA