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1、MyBatis 持久层的传统开发 - 上
1.1、创建项目
**GroupId:**com.tianyi
**ArtifactId:**mb004
**Version:**1.0-SNAPSHOT
1.2、修改 pom.xml 加入包
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.tianyi</groupId>
<artifactId>mb004</artifactId>
<version>1.0-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.5</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.11</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
</dependencies>
</project>
1.3、创建实体类(User.java)
package com.tianyi.javabean;
import java.io.Serializable;
import java.util.Date;
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 String getUsername() {return username;
}
public Date getBirthday() {return birthday;
}
public String getSex() {return sex;
}
public String getAddress() {return address;
}
public void setId(Integer id) {this.id = id;
}
public void setUsername(String username) {this.username = username;
}
public void setBirthday(Date birthday) {this.birthday = birthday;
}
public void setSex(String sex) {this.sex = sex;
}
public void setAddress(String address) {this.address = address;
}
@Override
public String toString() {return "User{" +
"id=" + id +
", username='" + username + '\'' +
", birthday=" + birthday +
", sex='" + sex + '\'' +
", address='" + address + '\'' +
'}';
}
}
1.4、创建持久层接口(IUserDao.java)
package com.tianyi.dao;
import com.tianyi.javabean.User;
import java.util.List;
public interface IUserDao {List<User> findAll();
User findById(Integer id);
int addUser(User u);
int updateUser(User u);
int deleteUser(Integer id);
int allCount();
List<User> findByName(String username);
}
1.5、创建持久层实现类(UserDaoImpl.java)
package com.tianyi.dao.impl;
import com.tianyi.dao.IUserDao;
import com.tianyi.javabean.User;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import java.util.List;
public class UserDaoImpl implements IUserDao {private SqlSessionFactory factory;
public UserDaoImpl(SqlSessionFactory factory) {this.factory = factory;
}
public List<User> findAll() {SqlSession session = factory.openSession();
List<User> users = session.selectList("com.tianyi.dao.IUserDao.findAll");
session.close();
return users;
}
public User findById(Integer id) {SqlSession session =factory.openSession();
User user = session.<User>selectOne("com.tianyi.dao.IUserDao.findById", id);
session.close();
return user;
}
public int addUser(User u) {SqlSession session =factory.openSession();
int n=session.insert("com.tianyi.dao.IUserDao.addUser",u);
session.commit();
session.close();
return n;
}
public int updateUser(User u) {SqlSession session =factory.openSession();
int n=session.update("com.tianyi.dao.IUserDao.updateUser",u);
session.commit();
session.close();
return n;
}
public int deleteUser(Integer id) {SqlSession session =factory.openSession();
int n=session.delete("com.tianyi.dao.IUserDao.deleteUser",id);
session.commit();
session.close();
return n;
}
public int allCount() {SqlSession session =factory.openSession();
int n=session.selectOne("com.tianyi.dao.IUserDao.allCount");
session.close();
return n;
}
public List<User> findByName(String username) {SqlSession session =factory.openSession();
List<User> users=session.selectList("com.tianyi.dao.IUserDao.findByName",username);
session.close();
return users;
}
}
2、MyBatis 持久层的传统开发 - 中
2.1、持久层的映射配置(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.tianyi.dao.IUserDao">
<select id="findAll" resultType="com.tianyi.javabean.User">
select * from user
</select>
<select id="findById" resultType="com.tianyi.javabean.User" parameterType="int">
select * from user where id=#{id}
</select>
<insert id="addUser" parameterType="com.tianyi.javabean.User">
<selectKey keyColumn="id" keyProperty="id" resultType="java.lang.Integer">
select last_insert_id()
</selectKey>
insert into user (username,birthday,sex,address)values(#{username},#{birthday},#{sex},#{address})
</insert>
<update id="updateUser" parameterType="com.tianyi.javabean.User">
update user set username=#{username},birthday=#{birthday},sex=#{sex},address=#{address} where id=#{id}
</update>
<delete id="deleteUser" parameterType="java.lang.Integer">
delete from user where id=#{id}
</delete>
<select id="allCount" resultType="java.lang.Integer">
select count(*) from user
</select>
<select id="findByName" parameterType="java.lang.String" resultType="com.tianyi.javabean.User" >
select * from user where username like #{username}
</select>
</mapper>
2.2、创建 SqlMapConfig.xml 文件
<?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 mybatis 的环境 -->
<environments default="mysql">
<!-- 配置 mysql 的环境 -->
<environment id="mysql">
<!-- 配置事务的类型 -->
<transactionManager type="JDBC"></transactionManager>
<!-- 配置连接数据库的信息: 用的是数据源 (连接池) -->
<dataSource type="POOLED">
<!-- <property name="driver" value="com.mysql.jdbc.Driver"/>-->
<property name="driver" value="com.mysql.cj.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/mb"/>
<property name="username" value="root"/>
<property name="password" value="root1234"/>
</dataSource>
</environment>
</environments>
<!-- 告知 mybatis 映射配置的位置 -->
<mappers>
<mapper resource="com/tianyi/dao/IUserDao.xml"/>
</mappers>
</configuration>
3、MyBatis 持久层的传统开发 - 下
3.1、编写测试类(MbTest.java)
package com.tianyi.test;
import com.tianyi.dao.IUserDao;
import com.tianyi.dao.impl.UserDaoImpl;
import com.tianyi.javabean.User;
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 org.junit.Test;
import java.io.InputStream;
import java.util.Date;
import java.util.List;
public class MbTest {private InputStream in ;
private SqlSessionFactory factory;
private IUserDao userDao;
@Test
public void findAll(){List<User> users = userDao.findAll();
for(User user : users) {System.out.println(user);
}
}
@Test
public void findById(){User user=userDao.findById(8);
System.out.println(user.toString());
}
@Test
public void addUser(){User user=new User();
user.setUsername("李国");
user.setSex("男");
user.setAddress("北京昌平");
user.setBirthday(new Date());
int n=userDao.addUser(user);
System.out.println(n+":"+user.getId());
}
@Test
public void updateUser(){User user=new User();
user.setId(10);
user.setUsername("李国");
user.setSex("男");
user.setAddress("北京昌平");
user.setBirthday(new Date());
int n=userDao.updateUser(user);
System.out.println(n+":"+user.getId());
}
@Test
public void deleteUser(){int n=userDao.deleteUser(19);
System.out.println(n);
}
@Test
public void allCount(){int n=userDao.allCount();
System.out.println(n);
}
@Test
public void findByName(){List<User> users=userDao.findByName("王 %");
for(User user:users){System.out.println(user);
}
}
@After// 在测试方法执行完成之后执行
public void destroy() throws Exception{in.close();
}
@Before// 在测试方法执行之前执行
public void init()throws Exception {//1. 读取配置文件
in = Resources.getResourceAsStream("SqlMapConfig.xml");
//2. 创建构建者对象
SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
//3. 创建 SqlSession 工厂对象
factory = builder.build(in);
//4、初始化 userDao
userDao=new UserDaoImpl(factory);
}
}
注意:
pom.xml
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.9</maven.compiler.source>
<maven.compiler.target>1.9</maven.compiler.target>
</properties>
SqlMapConfig.xml
jdbc:mysql://192.168.1.123:3306/mybatis?serverTimezone=UTC
正文完
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