一、搭建环境
1、创建maven工程并导入坐标
2、创建实体类和持久层dao接口
实体类
package com.wedu.mybatis05.domain;
import java.io.Serializable;
import java.util.Date;
/**
* 用户实体
*/
public class User implements Serializable {
private Integer id;
private String username;
private Date birthday;
private String sex;
private String address;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", username='" + username + '\'' +
", birthday=" + birthday +
", sex='" + sex + '\'' +
", address='" + address + '\'' +
'}';
}
}
dao接口
package com.wedu.mybatis05.dao;
/**
* 用户持久层接口
*/
public interface IUserDao {
}
3、创建mybatis配置文件:SqlMapConfig.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration
PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<!--配置环境-->
<environments default="mysql">
<!--配置mysql的环境-->
<environment id="mysql">
<!--配置事务的类型-->
<transactionManager type="JDBC"></transactionManager>
<!--配置数据源-->
<dataSource type="POOLED">
<!-- 配置连接数据库的基本信息 -->
<property name="driver" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/test?useSSL=true&useUnicode=true&characterEncoding=utf8"/>
<property name="username" value="root"/>
<property name="password" value="123456"/>
</dataSource>
</environment>
</environments>
<!--配置映射文件的位置-->
<mappers>
<mapper resource="com/wedu/mybatis05/dao/IUserDao.xml"/>
</mappers>
</configuration>
4、创建映射文件:IUserDao.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.wedu.mybatis05.dao.IUserDao">
</mapper>
5、创建测试类
package com.wedu.mybatis05.dao;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.After;
import org.junit.Before;
import java.io.IOException;
/**
* mybatis基于XML的CRUD
*/
public class UserDaoTest {
private SqlSession session;
private IUserDao userDao;
@Before
public void init() throws IOException{
//1.读取配置文件并创建SqlSessionFactory工厂
SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(Resources.getResourceAsStream("SqlMapConfig.xml"));
//2.使用工厂生产SqlSession对象
session = factory.openSession();
//3.使用SqlSession创建Dao接口的代理对象
userDao = session.getMapper(IUserDao.class);
}
@After
public void destroy() {
//5.释放资源
session.close();
}
}
二、CRUD操作
1、添加操作
1.1、在IUserDao中添加insert方法
/**
* 添加数据
* @param user
*/
void save(User user);
1.2、在IUserDao.xml中添加sql语句
<!--添加用户-->
<insert id="save" parameterType="com.wedu.mybatis05.domain.User">
INSERT INTO USER (username,birthday,sex,address) VALUES (#{username},#{birthday},#{sex},#{address})
</insert>
1.3、测试添加功能
/**
* 添加用户
*/
@Test
public void testSave() {
User user = new User();
user.setUsername("zhangsan");
user.setBirthday(new Date());
user.setSex("男");
user.setAddress("上海");
userDao.save(user);
//增删改需要事务提交才会更新数据库
session.commit();
}
2、更新操作
2.1、在IUserDao中添加update方法
/**
* 更新数据
* @param user
*/
void update(User user);
2.2、在IUserDao.xml中添加sql语句
<!--根据id更新用户-->
<update id="update" parameterType="com.wedu.mybatis05.domain.User">
update user set username = #{username},birthday = #{birthday},sex = #{sex},address = #{address} where id = #{id}
</update>
2.3、测试更新功能
/**
* 更新用户
*/
@Test
public void testUpdate() {
User user = new User();
user.setId(50);
user.setUsername("lisi");
user.setBirthday(new Date());
user.setSex("女");
user.setAddress("北京");
userDao.update(user);
//增删改需要事务提交
session.commit();
}
3、查询操作
3.1、在IUserDao中添加select方法
/**
* 根据id查询用户
* @param id
* @return
*/
User findById(Integer id);
3.2、在IUserDao.xml中添加sql语句
<!--根据id查询用户-->
<select id="findById" parameterType="Integer" resultType="com.wedu.mybatis05.domain.User">
select * from user where id = #{id}
</select>
3.3、测试查询功能
/**
* 根据id查询用户
*/
@Test
public void testfindById() {
User user = userDao.findById(50);
System.out.println(user);
}
4、删除操作
4.1、在IUserDao中添加select方法
/**
* 删除数据
* @param id
*/
void delete(Integer id);
4.2、在IUserDao.xml中添加sql语句
<!--删除用户-->
<delete id="delete" parameterType="Integer">
delete from user where id = #{id}
</delete>
4.3、测试删除功能
/**
* 删除用户
*/
@Test
public void testDelete() {
userDao.delete(50);
session.commit();
}
5、模糊查询
5.1、在IUserDao中添加模糊查询方法
/**
* 模糊查询
* @param username
* @return
*/
List<User> findByName(String username);
5.2、在IUserDao.xml中添加sql语句
<!--根据名称查询用户-->
<select id="findByName" parameterType="String" resultType="com.wedu.mybatis05.domain.User">
<!--select * from user where username like '%${username}%'-->
select * from user where username like #{username}
</select>
5.3、测试模糊查询功能
/**
* 模糊查询
*/
@Test
public void testfindByName() {
//List<User> users = userDao.findByName("王");//select * from user where username like '%王%'
List<User> users = userDao.findByName("%王%");//select * from user where username like ?
for (User user : users) {
System.out.println(user);
}
}