Spring Data JPA 规范Dao层接口

实体类

/**
 * 1.实体类和表的映射关系
 *      @Eitity
 *      @Table
 * 2.类中属性和表中字段的映射关系
 *      @Id
 *      @GeneratedValue
 *      @Column
 */
@Data
@Entity
@Table(name="cst_customer")
public class Customer {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name="cust_id")
    private Long custId;
    @Column(name="cust_address")
    private String custAddress;
    @Column(name="cust_industry")
    private String custIndustry;
    @Column(name="cust_level")
    private String custLevel;
    @Column(name="cust_name")
    private String custName;
    @Column(name="cust_phone")
    private String custPhone;
    @Column(name="cust_source")
    private String custSource;


}

Dao

/**
* JpaRepository<实体类类型，主键类型>：用来完成基本CRUD操作
* JpaSpecificationExecutor<实体类类型>：用于复杂查询（分页等查询操作）
*/                                                //实体类  主键类型
public interface CustomerDao extends JpaRepository<Customer,Long> {
}

整合 Spring Data JPA 与 Spring

<?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:aop="http://www.springframework.org/schema/aop"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:jdbc="http://www.springframework.org/schema/jdbc" xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:jpa="http://www.springframework.org/schema/data/jpa" xmlns:task="http://www.springframework.org/schema/task"
       xsi:schemaLocation="
		http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
		http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
		http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc.xsd
		http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd
		http://www.springframework.org/schema/data/jpa
		http://www.springframework.org/schema/data/jpa/spring-jpa.xsd">

    <!--spring 和 spring data jpa的配置-->

    <!-- 1.创建entityManagerFactory对象交给spring容器管理-->
    <bean id="entityManagerFactoty" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <property name="dataSource" ref="dataSource" />
        <!--配置的扫描的包（实体类所在的包） -->
        <property name="packagesToScan" value="cn.itcast.domain" />
        <!-- jpa的实现厂家 -->
        <property name="persistenceProvider">
            <bean class="org.hibernate.jpa.HibernatePersistenceProvider"/>
        </property>

        <!--jpa的供应商适配器 -->
        <property name="jpaVendorAdapter">
            <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
                <!--配置是否自动创建数据库表 -->
                <property name="generateDdl" value="false" />
                <!--指定数据库类型 -->
                <property name="database" value="MYSQL" />
                <!--数据库方言：支持的特有语法 -->
                <property name="databasePlatform" value="org.hibernate.dialect.MySQLDialect" />
                <!--是否显示sql -->
                <property name="showSql" value="true" />
            </bean>
        </property>

        <!--jpa的方言 ：高级的特性 -->
        <property name="jpaDialect" >
            <bean class="org.springframework.orm.jpa.vendor.HibernateJpaDialect" />
        </property>

    </bean>

    <!--2.创建数据库连接池 -->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="user" value="root"></property>
        <property name="password" value="0000"></property>
        <property name="jdbcUrl" value="jdbc:mysql:///jpa" ></property>
        <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
    </bean>

    <!--3.整合spring dataJpa-->
    <jpa:repositories base-package="cn.itcast.dao" transaction-manager-ref="transactionManager"
                   entity-manager-factory-ref="entityManagerFactoty" ></jpa:repositories>

    <!--4.配置事务管理器 -->
    <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
        <property name="entityManagerFactory" ref="entityManagerFactoty"></property>
    </bean>

    <!-- 4.txAdvice-->
    <tx:advice id="txAdvice" transaction-manager="transactionManager">
        <tx:attributes>
            <tx:method name="save*" propagation="REQUIRED"/>
            <tx:method name="insert*" propagation="REQUIRED"/>
            <tx:method name="update*" propagation="REQUIRED"/>
            <tx:method name="delete*" propagation="REQUIRED"/>
            <tx:method name="get*" read-only="true"/>
            <tx:method name="find*" read-only="true"/>
            <tx:method name="*" propagation="REQUIRED"/>
        </tx:attributes>
    </tx:advice>

    <!-- 5.aop-->
    <aop:config>
        <aop:pointcut id="pointcut" expression="execution(* cn.itcast.service.*.*(..))" />
        <aop:advisor advice-ref="txAdvice" pointcut-ref="pointcut" />
    </aop:config>


    <!--5.声明式事务 -->

    <!-- 6. 配置包扫描-->
    <context:component-scan base-package="cn.itcast" ></context:component-scan>
</beans>

测试类

/**
 * @Author: 刚满20就秃顶
 * @Code:
 */

    @RunWith(SpringJUnit4ClassRunner.class)
    @ContextConfiguration(locations = "classpath:applicationContext.xml")
    public class CustomerDaoTest {

        @Autowired
        private CustomerDao customerDao;

        /**
         * 保存客户：调用save(obj)方法
         */
        @Test
        public void testSave() {
            Customer c = new Customer();
            c.setCustName("小南");
            customerDao.save(c);
        }

        /**
         * 修改客户：调用save(obj)方法
         * 对于save方法的解释：如果执行此方法是对象中存在id属性，即为更新操作会先根据id查询，再更
         * 新
         * 如果执行此方法中对象中不存在id属性，即为保存操作
         */
        @Test
        public void testUpdate() {
            //根据id查询id为1的客户
            Customer customer = customerDao.findOne(1l);
            //修改客户名称
            customer.setCustName("枫叶");
            //更新
            customerDao.save(customer);
        }

        /**
         * 根据id删除：调用delete(id)方法
         */
        @Test

        public void testDelete() {
            customerDao.delete(1l);
        }

        /**
         * 根据id查询：调用findOne(id)方法
         */
        @Test
        public void testFindById() {
            Customer customer = customerDao.findOne(2l);
            System.out.println(customer);
        }
    }
}