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准备表
创建项目并导包
创建User类
package pers.zhang.po;
import java.io.Serializable;
import java.util.Date;
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
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 String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
@Override
public String toString() {
return "User [id=" + id + ", username=" + username + ", sex=" + sex
+ ", birthday=" + birthday + ", address=" + address + "]";
}
}
书写配置文件
log4j.properties:
# Global logging configuration
log4j.rootLogger=ERROR,stdout
# MyBatis logging configuration...
log4j.logger.pers.zhang=DEBUG
# 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
jdbc.properties:
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/mybatis?characterEncoding=utf-8
jdbc.username=root
jdbc.password=123456
sqlMapCongfig.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>
<properties resource="jdbc.properties"/>
<!-- 别名 包以其子包下所有类 头字母大小都行-->
<typeAliases>
<package name="pers.zhang.po"/>
</typeAliases>
<!-- 和spring整合后 environments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="${jdbc.driver}" />
<property name="url"
value="jdbc:mysql://localhost:3306/mybatis?characterEncoding=utf-8" />
<property name="username" value="root" />
<property name="password" value="123456" />
</dataSource>
</environment>
</environments>
<!-- Mapper的位置 Mapper.xml 写Sql语句的文件的位置 -->
<mappers>
<mapper resource="pers/zhang/mapper/UserMapper.xml" />
</mappers>
</configuration>
映射文件UserMapper.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">
<!-- 写Sql语句 -->
<mapper namespace="test">
<!-- 通过ID查询一个用户 -->
<select id="findUserById" parameterType="Integer" resultType="User">
select * from user where id = #{v}
</select>
<!-- //根据用户名称模糊查询用户列表
#{} select * from user where id = ？ 占位符 ? == '五'
${} select * from user where username like '%五%' 字符串拼接
-->
<select id="findUserByUsername" parameterType="String" resultType="pers.zhang.po.User">
select * from user where username like "%"#{haha}"%"
</select>
<!-- 添加用户 -->
<insert id="insertUser" parameterType="pers.zhang.po.User">
<selectKey keyProperty="id" resultType="Integer" order="AFTER">
select LAST_INSERT_ID()
</selectKey>
insert into user (username,birthday,address,sex)
values (#{username},#{birthday},#{address},#{sex})
</insert>
<!-- 更新 -->
<update id="updateUserById" parameterType="pers.zhang.po.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 = #{vvvvv}
</delete>
</mapper>
查询
@Test
public void testMybatis() throws Exception {
//加载核心配置文件
String resource = "sqlMapConfig.xml";
InputStream in = Resources.getResourceAsStream(resource);
//创建SqlSessionFactory
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(in);
//创建SqlSession
SqlSession sqlSession = sqlSessionFactory.openSession();
//执行Sql语句
User user = sqlSession.selectOne("findUserById", 1);
System.out.println(user);
}
控制台打印：
User [id=1, username=王五, sex=0, birthday=Fri Oct 25 00:00:00 CST 2019, address=北京]
模糊查询
@Test
public void testfindUserByUsername() throws Exception {
//加载核心配置文件
String resource = "sqlMapConfig.xml";
InputStream in = Resources.getResourceAsStream(resource);
//创建SqlSessionFactory
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(in);
//创建SqlSession
SqlSession sqlSession = sqlSessionFactory.openSession();
//执行Sql语句
List<User> users = sqlSession.selectList("findUserByUsername", "五");
for (User user2 : users) {
System.out.println(user2);
}
}
控制台打印：
User [id=1, username=王五, sex=0, birthday=Fri Oct 25 00:00:00 CST 2019, address=北京]
User [id=5, username=五菱宏光, sex=null, birthday=null, address=null]
insert操作
@Test
public void testInsertUser() throws Exception {
//加载核心配置文件
String resource = "sqlMapConfig.xml";
InputStream in = Resources.getResourceAsStream(resource);
//创建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("李雷");
user.setBirthday(new Date());
user.setAddress("北京");
user.setSex("男");
int i = sqlSession.insert("insertUser", user);
sqlSession.commit();
System.out.println(user.getId());
}
update操作
@Test
public void testUpdateUserById() throws Exception {
//加载核心配置文件
String resource = "sqlMapConfig.xml";
InputStream in = Resources.getResourceAsStream(resource);
//创建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(1);
user.setUsername("修改后的王五");
user.setBirthday(new Date());
user.setAddress("北京");
user.setSex("0");
int i = sqlSession.update("test.updateUserById", user);
sqlSession.commit();
}
delete操作
@Test
public void testDelete() throws Exception {
//加载核心配置文件
String resource = "sqlMapConfig.xml";
InputStream in = Resources.getResourceAsStream(resource);
//创建SqlSessionFactory
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(in);
//创建SqlSession
SqlSession sqlSession = sqlSessionFactory.openSession();
sqlSession.delete("test.deleteUserById", 1);
sqlSession.commit();
}
