JPA与Spring的简单整合

╰半橙微兮° 2022-05-21 08:00 208阅读 0赞

**`spring配置文件`**

<?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">
    
        
        <context:component-scan base-package="com.heiketu"/>
    
        
        <context:property-placeholder location="classpath:db.properties"/>
    
        
        <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
            <property name="user" value="${jdbc.user}"/>
            <property name="password" value="${jdbc.pass}"/>
            <property name="jdbcUrl" value="${jdbc.url}"/>
            <property name="driverClass" value="${jdbc.driver}"/>
        </bean>
    
        
        <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
            <property name="dataSource" ref="dataSource"/>
            
            <property name="jpaVendorAdapter">
                <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"/>
            </property>
            
            <property name="packagesToScan" value="com.heiketu.pojo"/>
            <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>
    
        
        <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
            <property name="entityManagerFactory" ref="entityManagerFactory"/>
        </bean>
    
        
        <tx:annotation-driven transaction-manager="transactionManager" />
    
    </beans>

`数据源的properties`

jdbc.user=root
    jdbc.pass=admin
    jdbc.url=jdbc:mysql:///test?serverTimezone=GMT%2B8
    # com.mysql.cj.jdbc.Driver -> MySQL7.0以上的版本驱动class 有所更改
    jdbc.driver=com.mysql.jdbc.Driver

`Spring`中使用`JPA`:  
在Dao层通过`@PersistenceContext`注解，获取到`EntityManager`即可使用JPA，代码如下:

@Repository
    public class TestDao { 
    
        @PersistenceContext
        private EntityManager entityManager;
    
        public void save(TestClass testClass){
            entityManager.persist(testClass);
        }
    
    }

`@Repository`容器为`Spring`容器的注解，使用该注解将该Dao加入到spring容器，交由Spring来管理。

JPA与Spring整合使用到的测试Jar包示例如下:

**`hiberante的JPA实现所需Jar包:`**

`required目录下`

![70][]

`c3p0数据源`

![70 1][]

`JPA规范包`

![70 2][]

`Spring相关Jar包`:

![70 3][]

`MySQL驱动包`

![70 4][]

[70]: /images/20220521/490b3f2354954d60a35df1216526b87e.png
[70 1]: /images/20220521/91e0d9b0c0744a1e948f38d2a8423fe9.png
[70 2]: /images/20220521/cf0d502b22e440acbdc2cb7d5b0c22b5.png
[70 3]: /images/20220521/fb3f6a844016473abce6f5fae151d6bd.png
[70 4]: /images/20220521/cb80c5479cf74a0b93b45f8d673a1387.png