Spring 整合 JPA
spring 整合 jpa 客户的基本CRUD
依赖
<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 beg -->
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>1.6.8</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aop</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-orm</artifactId>
<version>${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 end -->
<!-- hibernate beg -->
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-core</artifactId>
<version>${hibernate.version}</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>${hibernate.version}</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-validator</artifactId>
<version>5.2.1.Final</version>
</dependency>
<!-- hibernate end -->
<!-- c3p0 beg -->
<dependency>
<groupId>c3p0</groupId>
<artifactId>c3p0</artifactId>
<version>${c3p0.version}</version>
</dependency>
<!-- c3p0 end -->
<!-- log end -->
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>${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>
<!-- log end -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>${mysql.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-jpa</artifactId>
<version>1.9.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>4.2.4.RELEASE</version>
</dependency>
<!-- el beg 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>
spring-jpa 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: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">
<!-- 1.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:///jpa"/>
<property name="user" value="root"/>
<property name="password" value="root"/>
</bean>
<!-- 2.配置entityManagerFactory -->
<bean id="entityManagerFactory"
class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="dataSource"/>
<property name="packagesToScan" value="cn.itcast.entity"/>
<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">
<property name="generateDdl" value="true"/>
<property name="database" value="MYSQL"/>
<property name="databasePlatform"
value="org.hibernate.dialect.MySQLDialect"/>
<property name="showSql" value="true"/>
</bean>
</property>
<property name="jpaDialect">
<bean class="org.springframework.orm.jpa.vendor.HibernateJpaDialect"/>
</property>
</bean>
<!-- 3.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>
<!-- 整合spring data jpa-->
<jpa:repositories base-package="cn.itcast.dao"
transaction-manager-ref="transactionManager"
entity-manager-factory-ref="entityManagerFactory"></jpa:repositories>
<!-- 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>
<context:component-scan base-package="cn.itcast"></context:component-scan>
<!--组装其它 配置文件-->
</beans>
实体类
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
/**
* 所有的注解都是使用JPA的规范提供的注解，
* 所以在导入注解包的时候，一定要导入javax.persistence下的
*/
@Entity //声明实体类
@Table(name="cst_customer") //建立实体类和表的映射关系
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")//指定和表中cust_source字段的映射关系
private String custSource;
@Column(name="cust_industry")//指定和表中cust_industry字段的映射关系
private String custIndustry;
@Column(name="cust_level")//指定和表中cust_level字段的映射关系
private String custLevel;
@Column(name="cust_address")//指定和表中cust_address字段的映射关系
private String custAddress;
@Column(name="cust_phone")//指定和表中cust_phone字段的映射关系
private String custPhone;
}
编写符合 Spring Data JPA 规范的 Dao 层接口
在 Spring Data JPA 中，对于定义符合规范的 Dao 层接口，我们只需要遵循以下几点就可以了：
- 创建一个 Dao 层接口，继承 JpaRepository 和 JpaSpecificationExecutor 接口
- 提供相应的泛型
public interface CustomerDao extends JpaRepository<Customer, Long>, JpaSpecificationExecutor<Customer> {
// jpql 查全部
@Query("from Customer")
List<Customer> findAll();
// jpql 条件查询
@Query("from Customer where cust_name = ?1")
List<Customer> findByCustName(String custName);
// jpql 更新 @Modifying 执行更新操作
@Query("update Customer set cust_address = ?2 where cust_id = ?1")
@Modifying
void updateCustAddress(Long custId, String custAddress);
// 原生 sql
@Query(value = "select * from cst_customer", nativeQuery = true)
List<Customer> findSql();
//方法命名规则查询
List<Customer> findByCustAddress(String custAddress);
List<Customer> findByCustAddressLikeAndCustNameLike(String custAddress, String custName);
}
方法命名规则查询
就是在定义我们的查询方法的时候，需要按照spring data jpa所指定的命名规则进行命名
findBy + 方法属性名 + 查询方式 + [逻辑连接符 + 方法属性名 + 查询方式]...
优缺点：简单，但是如果条件特别多将导致方法名冗长。实际中方法命名和 jpql 结合使用。
jpql 查询
使用的是类名和属性名。@Query @Modifying
sql 查询
使用的是表名和字段名。@Query nativeQuery = true
测试类
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "classpath:spring/spring-jpa.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("传智播客");
customerDao.save(c);
}
/**
* 修改客户：调用save(obj)方法
* 根据是否存在 id ，进行保存或更新。
*/
@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("传智播客顺义校区");
//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(1L);
System.out.println(customer);
}
// jpql 查询
@Test
public void testFindAll(){
List<Customer> customerList = customerDao.findAll();
System.out.println(customerList);
}
@Test
public void testFindByCustName(){
List<Customer> customerList = customerDao.findByCustName("传智播客1");
System.out.println(customerList);
}
/**
* SpringDataJpa 更新/删除操作
* * 需要手动开启事务
* * 执行完毕后会回滚事务
* @Rollback : 设置是否回滚 false|true
*/
@Test
@Transactional
@Rollback(false)
public void testUpdateCustAddress(){
customerDao.updateCustAddress(1L, "西安校区");
}
// 方法命名查询
@Test
public void testFindByCustAddress(){
List<Customer> customerList = customerDao.findByCustAddress("西安校区");
System.out.println(customerList);
}
@Test
public void testFindByCustAddressLikeAndCustNameLike(){
List<Customer> customerList = customerDao.findByCustAddressLikeAndCustNameLike("西安%", "传智%");
System.out.println(customerList);
}
// sql 查询
@Test
public void testFindSql(){
List<Customer> customerList = customerDao.findSql();
System.out.println(customerList);
}
}
bugs
org.springframework.dao.InvalidDataAccessApiUsageException: Executing an update/delete query; nested exception is javax.persistence.TransactionRequiredException: Executing an update/delete query
原因：SpringDataJpa 更新/删除操作，必须手动加事务
org.springframework.dao.InvalidDataAccessResourceUsageException: could not extract ResultSet; SQL [n/a]; nested exception is org.hibernate.exception.SQLGrammarException: could not extract ResultSet
原因：sql 查询使用的是表名，不是实体名
@Query(value = "select * from Customer", nativeQuery = true)//错误
List<Customer> findSql();
