一、mybatis下载
下载地址：https://github.com/mybatis/mybatis-3/releases
mybatis-3.2.7.jar mybatis的核心包
lib文件夹 mybatis的依赖包所在
mybatis-3.2.7.pdf mybatis使用手册
二、创建java工程加入jar包
加入mybatis核心包、lib里面的所有的依赖包、数据库驱动包
三、加入配置文件
SqlMapConfig.xml:
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<?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> <!-- 别名 --> <typeAliases> <!-- <typeAlias type="com.itheima.mybatis.pojo.User" alias="User"/> --> <package name="com.itheima.mybatis.pojo"/> </typeAliases> <!-- 和spring整合后environment配置将废除 --> <environments default="development"> <environment id="development"> <!-- 使用jdbc事务管理 --> <transactionManager type="JDBC"/> <!-- 数据库连接池 --> <dataSource type="POOLED"> <property name="driver" value="com.mysql.jdbc.Driver"/> <property name="url" value="jdbc:mysql://localhost:3306/mybatis?characterEncoding=utf-8"/> <property name="username" value="root"/> <property name="password" value=""/> </dataSource> </environment> </environments> <!-- mapper的文件位置 --> <mappers> <mapper resource="User.xml"/> </mappers> </configuration>
log4j.properties:
# Global logging configuration log4j.rootLogger=DEBUG, stdout # Console output... log4j.appender.stdout=org.apache.log4j.ConsoleAppender log4j.appender.stdout.layout=org.apache.log4j.PatternLayout log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n
四、创建实体类
public class User implements Serializable {
private static final long serialVersionUID = 1L;
private Integer id;
private String username;// 用户姓名
private String sex;// 性别
private Date birthday;// 生日
private String address;// 地址
五、sql映射文件
在src下面创建User.xml或者在创建mapper接口的包里面创建并且名字和接口名字相同
<?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">
<!-- namespace命名空间，用于隔离sql -->
<mapper namespace="user">
<!-- 通过id查询一个用户 -->
<select id="findUserById" parameterType="Integer" resultType="com.itheima.mybatis.pojo.User">
select * from user where id=#{id}
</select>
<!-- 根据用户名称模糊查询用户列表
#{}占位符
${}字符串拼接
-->
<select id="findUserByUsername" parameterType="String" resultType="com.itheima.mybatis.pojo.User">
<!-- select * from user where username like '%${value}%'-->
select * from user where username like "%"#{v}"%"
<!--两条sql语句是一样的，第一句是select * from user where username like '%五%'
第二句是select * from user where uername like "%"'五'"%" -->
</select>
<!-- 添加用户 -->
<insert id="insertUser" parameterType="com.itheima.mybatis.pojo.User">
insert into user(username,birthday,address,sex)
values (#{username},#{birthday},#{address},#{sex})
</insert>
<!-- 更新用户 -->
<update id="updateUserById" parameterType="com.itheima.mybatis.pojo.User">
update user
set username=#{username},sex=#{sex},birthday=#{birthday},address=#{address}
where id=#{id}
</update>
<!-- 删除 -->
<delete id="deleteUserById" parameterType="Integer">
delete from user where id=#{id}
</delete>
</mapper>
六、测试类
public class MybatisFirstTest {
@Test
public void testname() throws IOException{
//加载核心配置文件
String resource="sqlMapConfig.xml";
InputStream in=Resources.getResourceAsStream(resource);
//创建一个sqlsessionfactory
SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(in);
//创建sqlsession
SqlSession sqlSession=sqlSessionFactory.openSession();
//执行sql语句
User user=sqlSession.selectOne("user.findUserById",10);
System.out.println(user);
}
//根据用户名称模糊查询用户列biao
@Test
public void testfindUserByUsername() throws IOException{
//加载核心配置文件
String resource="sqlMapConfig.xml";
InputStream in=Resources.getResourceAsStream(resource);
//创建一个sqlsessionfactory
SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(in);
//创建sqlsession
SqlSession sqlSession=sqlSessionFactory.openSession();
//执行sql语句
List<User> user=sqlSession.selectList("user.findUserByUsername","五");
for(User user2:user){
System.out.println(user2);
}
}
//添加用户
@Test
public void testInsertUser() throws IOException{
//加载核心配置文件
String resource="sqlMapConfig.xml";
InputStream in=Resources.getResourceAsStream(resource);
//创建一个sqlsessionfactory
SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(in);
//创建sqlsession
SqlSession sqlSession=sqlSessionFactory.openSession();
//执行sql语句
User user=new User();
user.setUsername("曾志伟");
user.setBirthday(new Date());
user.setAddress("河南");
user.setSex("男");
int i=sqlSession.insert("user.insertUser",user);
sqlSession.commit();
}
//更新用户
@Test
public void testUpdateUserById() throws IOException{
//加载核心配置文件
String resource="sqlMapConfig.xml";
InputStream in=Resources.getResourceAsStream(resource);
//创建一个sqlsessionfactory
SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(in);
//创建sqlsession
SqlSession sqlSession=sqlSessionFactory.openSession();
//执行sql语句
User user=new User();
user.setId(29);
user.setUsername("何炅");
user.setBirthday(new Date());
user.setAddress("湖南");
user.setSex("男");
int i=sqlSession.update("user.updateUserById",user);
sqlSession.commit();
}
//删除
@Test
public void testDelete() throws IOException{
//加载核心配置文件
String resource="sqlMapConfig.xml";
InputStream in=Resources.getResourceAsStream(resource);
//创建一个sqlsessionfactory
SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(in);
//创建sqlsession
SqlSession sqlSession=sqlSessionFactory.openSession();
sqlSession.delete("user.deleteUserById",29);
sqlSession.commit();
}
}