SpringData入门笔记(三) - SpringData初尝鲜

目标

用sring data方式创建一张employee表，包含id/name/age字段，id自增，name长度20，name/age不能为空。

创建一个通过name查询employee的方法，并测试之。

项目结构

Maven依赖

<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.38</version>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-jpa</artifactId>
<version>1.8.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>4.3.6.Final</version>
</dependency>

代码编写

建立对象模型

Employee.java

package com.dotleo.entity;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

/**
* 雇员 : 先开发实体类 ---> 自动生成数据库
* @author LiuFei
* @create 2017-11-06 21:23
*/
@Entity
public class Employee {

@GeneratedValue
@Id
private Integer id;

@Column(length = 20 ,nullable = false)
private String name;

@Column(nullable = false)
private Integer age;

public Integer getId() {
return id;
}

public void setId(Integer id) {
this.id = id;
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public Integer getAge() {
return age;
}

public void setAge(Integer age) {
this.age = age;
}

@Override
public String toString() {
return "Employee{" +
"id=" + id +
", name='" + name + '\'' +
", age=" + age +
'}';
}
}

spring配置文件 - beans.xml 创建

此文件为最终版，可能由于部分类还没创建报错，暂时不用管

beans.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:context="http://www.springframework.org/schema/context"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:jpa="http://www.springframework.org/schema/data/jpa"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.3.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd"> 
<!-- 1.配置数据源 -->
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver" />
<property name="url" value="jdbc:mysql://localhost:3306/spring_data?useSSL=true" />
<property name="username" value="root" />
<property name="password" value="liufei" />
</bean>

<!--2 配置EntityManagerFactory-->
<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.dotleo"/>

<property name="jpaProperties">
<props>
<prop key="hibernate.ejb.naming_strategy">org.hibernate.cfg.ImprovedNamingStrategy</prop>
<prop key="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.format_sql">true</prop>
<prop key="hibernate.hbm2ddl.auto">update</prop>
</props>
</property>

</bean>

<!--3 配置事务管理器-->
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory"/>
</bean>

<!--4 配置支持注解的事务-->
<tx:annotation-driven transaction-manager="transactionManager"/>

<!--5 配置spring data-->
<jpa:repositories base-package="com.dotleo" entity-manager-factory-ref="entityManagerFactory"/>

<context:component-scan base-package="com.dotleo"/>
</beans>

EmployeeRepository接口创建

package com.dotleo.repository;

import com.dotleo.entity.Employee;
import org.springframework.data.repository.Repository;

/**
* @author LiuFei
* @create 2017-11-06 22:44
*/
public interface EmployeeRepository extends Repository<Employee, Integer>{

public Employee findByName(String name);
}

测试类创建

package com.dotleo.repository;

import com.dotleo.entity.Employee;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

/**
* @author LiuFei
* @create 2017-11-06 22:48
*/
public class EmployeeRepositoryTest {

ApplicationContext ctx = null;
EmployeeRepository employeeRepository = null;

@Before
public void setup() {
ctx = new ClassPathXmlApplicationContext("beans.xml");
employeeRepository = ctx.getBean(EmployeeRepository.class);
}

@After
public void tearDown() {
ctx = null;
}

@Test
public void testFindByName() {
Employee employee = employeeRepository.findByName("zhangsan");
if (employee != null) {
System.out.println(employee.toString());
}
}

}