day2：springdatajpa的运行原理以及基本操作 （上）
第一 springDataJpa的概述
1.3 Spring Data JPA 与 JPA和hibernate之间的关系
07.入门案例
第二 springDataJpa的入门操作
案例：客户的基本CRUD
i.搭建环境
创建工程导入坐标
配置spring的配置文件（配置spring Data jpa的整合）
编写实体类（Customer），使用jpa注解配置映射关系
ii.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dao层接口的实现类
* dao层接口规范
.需要继承两个接口（JpaRepository，JpaSpecificationExecutor）
.需要提供响应的泛型
入门案例用到的method
*
findOne（id） ：根据id查询
save(customer):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
2.2 搭建Spring Data JPA的开发环境
2.2.1 引入Spring Data JPA的依赖坐标
<properties>
<spring.version>4.3.6.RELEASE</spring.version>
<hibernate.version>5.3.5.Final</hibernate.version>
<slf4j.version>1.7.12</slf4j.version>
<log4j.version>1.2.17</log4j.version>
<c3p0.version>0.9.1.2</c3p0.version>
<mysql.version>8.0.17</mysql.version>
</properties> <dependencies>
<!-- junit单元测试 -->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency> <!-- spring beg -->
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>1.9.2</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>${hibernate.version}</version>
</dependency>
<!-- hibernate end --> <!-- c3p0 beg -->
<dependency>
<groupId>c3p0</groupId>
<artifactId>c3p0</artifactId>
<version>${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>${spring.version}</version>
</dependency> <!-- el beg 使用spring data jpa 必须引入 -->
<dependency>
<groupId>javax.el</groupId>
<artifactId>javax.el-api</artifactId>
<version>2.2.5</version>
</dependency> <dependency>
<groupId>org.glassfish.web</groupId>
<artifactId>javax.el</artifactId>
<version>2.2.4</version>
</dependency>
<!-- el end -->
</dependencies>
spring框架的配置文件
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"> <!--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.bjut.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="root"></property>
<property name="jdbcUrl" value="jdbc:mysql:///itheima?serverTimezone=Asia/Shanghai"></property>
<property name="driverClass" value="com.mysql.cj.jdbc.Driver"></property>
</bean> <!--3.整合spring dataJpa-->
<jpa:repositories base-package="cn.bjut.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.bjut.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.bjut" ></context:component-scan> </beans>
09-入门案例：创建客户实体类并配置映射关系
package cn.bjut.domain; import javax.persistence.*; /**
* 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
*/
@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; //=====下面是toString()方法和get/set方法=====//
10-入门案例：编写符合spring Data JPA规范的dao层接口
创建一个接口
cn.bjut.dao.CustomerDao
package cn.bjut.dao; import cn.bjut.domain.Customer;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.JpaSpecificationExecutor; /**
* 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> { }
然后创建一个测试类
cn.bjut.test.CustomerDaoTest
@RunWith(SpringJUnit4ClassRunner.class) //声明spring提供的单元测试环境
@ContextConfiguration(locations = "classpath:applicationContext.xml")//指定spring容器的配置信息
public class CustomerDaoTest {
@Autowired
private CustomerDao customerDao; /**
* 根据id查询
*/
@Test
public void testFindOne() {
Customer customer = customerDao.findOne(1l);
System.out.println(customer);
} }
直接在接口中定义查询方法，如果是符合规范的，可以不用写实现，目前支持的关键字写法如下：
12-入门案例：完成客户的添加和修改
/**
* 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("程序员");
customer.setCustLevel("vip");
customer.setCustIndustry("it教育");
customerDao.save(customer);
} @Test
public void testUpdate() {
Customer customer = new Customer();
customer.setCustId(3l);
customer.setCustName("程序员很厉害");
customerDao.save(customer);
}
13-入门案例：完成客户的删除
@Test
public void testDelete () {
customerDao.delete(3l);
}
14-入门案例：查询所有客户
/**
* 查询所有
*/
@Test
public void testFindAll() {
List<Customer> list = customerDao.findAll();
for(Customer customer : list) {
System.out.println(customer);
}
}
18-执行过程：执行过程已经内部处理流程的总结
====================
未完待续。。