7、Spring Data Jpa快速入门案例

Spring Data Jpa

1、快速入门

案例：客户的基本CRUD

1.搭建环境

​　　　创建工程导入坐标
​　　　配置spring的配置文件
　　　编写实体类(Customer)，使用jpa注解配置映射关系

2.编写一个符合springDataJpa的dao层接口

​　　　* 只需要编写dao层接口，不需要编写到dao层接口的实现类

​　　　* dao层接口规范

​　　　　　1.需要继承两个接口(JpaRepository,JpaSpecificationExecutor)

​　　　　　2.需要提供响应的泛型
　　　findOne(id)：根据id查询
　　　save（实体类对象）：把保存或者更新（依据：传递的实体类对象中，是否包含id属性）
　　　delete(id)：根据id删除
　　　findAll()：查询全部

2、操作步骤

2.1、导入坐标

<properties>
    <spring.version>4.2.4.RELEASE</spring.version>
    <hibernate.version>5.0.7.Final</hibernate.version>
    <slf4j.version>1.6.6</slf4j.version>
    <log4j.version>1.2.12</log4j.version>
    <c3p0.version>0.9.1.2</c3p0.version>
    <mysql.version>5.1.6</mysql.version>
</properties>

<dependencies>
    <!-- junit单元测试 -->
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.9</version>
        <scope>test</scope>
    </dependency>

    <!-- spring aop-->
    <dependency>
        <groupId>org.aspectj</groupId>
        <artifactId>aspectjweaver</artifactId>
        <version>1.6.8</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-aop</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <!--spring ioc-->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context-support</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-core</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <!--spring对orm框架的支持包-->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-orm</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <!-- hibernate核心包 -->
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-core</artifactId>
        <version>${hibernate.version}</version>
    </dependency>
    <!--hibernate对jpa实现的包-->
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-entitymanager</artifactId>
        <version>${hibernate.version}</version>
    </dependency>
    <!--hibernate的验证包-->
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-validator</artifactId>
        <version>5.2.1.Final</version>
    </dependency>
    <!-- c3p0  -->
    <dependency>
        <groupId>c3p0</groupId>
        <artifactId>c3p0</artifactId>
        <version>${c3p0.version}</version>
    </dependency>
    <!-- log-->
    <dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>${log4j.version}</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>${slf4j.version}</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-log4j12</artifactId>
        <version>${slf4j.version}</version>
    </dependency>
    <!--数据库-->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>${mysql.version}</version>
    </dependency>
    <!--spring data jpa的坐标-->
    <dependency>
        <groupId>org.springframework.data</groupId>
        <artifactId>spring-data-jpa</artifactId>
        <version>1.9.0.RELEASE</version>
    </dependency>
    <!--spring提供单元测试的坐标-->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <!-- el 使用spring data jpa 必须引入 -->
    <dependency>
        <groupId>javax.el</groupId>
        <artifactId>javax.el-api</artifactId>
        <version>2.2.4</version>
    </dependency>
    <dependency>
        <groupId>org.glassfish.web</groupId>
        <artifactId>javax.el</artifactId>
        <version>2.2.4</version>
    </dependency>
    <!-- el end -->
</dependencies>

2.2、编写spring整合spring data jpa的配置文件

(applicationContext.xml)

<?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">

    <!-- 创建entityManagerFactory对象交给spring容器管理 -->
    <bean id="entityManagerFactory" 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="com.sddm.entity" />
        <!-- 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">
                <!--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 -->
                <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>

    <!-- dataSource 配置数据库连接池-->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="com.mysql.jdbc.Driver" />
        <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/jpa" />
        <property name="user" value="root" />
        <property name="password" value="root" />
    </bean>

    <!-- 整合spring data jpa-->
    <jpa:repositories base-package="com.sddm.dao"
                      transaction-manager-ref="transactionManager"
                      entity-manager-factory-ref="entityManagerFactory"></jpa:repositories>

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

    <!-- 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>

    <!-- aop-->
    <aop:config>
        <aop:pointcut id="pointcut" expression="execution(* com.sddm.service.*.*(..))" />
        <aop:advisor advice-ref="txAdvice" pointcut-ref="pointcut" />
    </aop:config>
    
    <context:component-scan base-package="com.sddm"></context:component-scan>

    <!--组装其它 配置文件-->

</beans>

2.3、编写客户实体类

/*
* 1.实体类和表的映射关系
*       @Entity
*       @Table
* 2.类中属性和表中字段的映射关系
*       @Id
*       @GeneratedValue
*       @Column
* */
@Entity
@Table(name = "cst_customer")
public class Customer {
    
    
    @Id//声明当前私有属性为主键
    @GeneratedValue(strategy= GenerationType.IDENTITY) //配置主键的生成策略
    @Column(name="cust_id") //指定和表中cust_id字段的映射关系
    private Long custId;

    @Column(name="cust_name") //指定和表中cust_name字段的映射关系
    private String custName;

    @Column(name="cust_source")
    private String custSource;

    @Column(name="cust_industry")
    private String custIndustry;

    @Column(name="cust_level")
    private String custLevel;

    @Column(name="cust_address")
    private String custAddress;

    @Column(name="cust_phone")
    private String custPhone;
 	
 	//省略get/set方法
}

2.4、编写符合springDataJpa的dao层接口

/*
* 符合SpringDataJpa的dao层接口规范
*       JpaRepository<操作的实体类类型,实体类中主键属性的类型>
*           * 封装了基本CRUD操作
*       JpaSpecificationExecutor<操作的实体类类型>
*           * 封装了复杂查询（分页）
* */
public interface CustomerDao extends JpaRepository<Customer,Long>, JpaSpecificationExecutor<Customer> {
    
    
}

2.5、编写测试类CustomerDaoTest测试

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

根据id查询

@Autowired
CustomerDao customerDao;

@Test
public void testFindOne(){
    
    
    Customer customer = customerDao.findOne(2l);
    System.out.println(customer);
}

查看结果：

保存客户：

/*
* save：保存或者更新
*       根据传递的对象是否存在主键id,
*       如果没有id主键属性：保存
*       存在id主键属性，根据id查询数据，更新数据
* */
@Test
public void testSave(){
    
    
    Customer customer = new Customer();
    customer.setCustName("实达迪美");
    customer.setCustLevel("vip");
    customer.setCustIndustry("福州");
    customerDao.save(customer);
}

查看结果：

更新：

/*
* 更新
* */
@Test
public void testUpdate(){
    
    
    Customer customer = new Customer();
    customer.setCustId(6l);
    customer.setCustName("实达迪美牛逼");
    customer.setCustLevel("vip");
    customer.setCustIndustry("福州");
    customerDao.save(customer);
}

查看结果：

根据id删除：

/*
* 删除
* */
@Test
public void testDelete(){
    
    
	customerDao.delete(6l);
}

查看结果：

查询全部：

/*
* 查询全部
* */
@Test
public void testFindAll(){
    
    
    List<Customer> customers = customerDao.findAll();
    for (Customer customer:customers){
    
    
    	System.out.println(customer);
    }
}

查看结果：