01.Mybatis初级使用-初体验

首次使用Mybatis

0.新建maven工程，引入依赖

<dependency>  <groupId>mysql</groupId>  <artifactId>mysql-connector-java</artifactId>  <version>5.1.38</version></dependency>  <dependency>  <groupId>org.mybatis</groupId>  <artifactId>mybatis</artifactId>  <version>3.4.2</version></dependency>

1.在resource下新建jdbc.properties、roleMapper.xml、mysql-config.xml文件

jdbc.proerties

driver=com.mysql.jdbc.Driverurl=jdbc:mysql://localhost:3306/testuser=rootpassword=luzhen

com/lz/mybatis/mapper/roleMapper.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.lz.mybatis.model.RoleMapper"><select id="getRole" parameterType="java.lang.Integer" resultType="Role">select * from role where id = #{id}</select></mapper>

mybatis-config.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"/><typeAliases><package name="com.lz.mybatis.model"/></typeAliases><environments default="development"><environment id="development"><transactionManager type="JDBC"/><dataSource type="POOLED"><property name="driver" value="${driver}"/><property name="url" value="${url}"/><property name="user" value="${user}"/><property name="password" value="${password}"/></dataSource></environment></environments><mappers><package name="com.lz.mybatis.mapper"/></mappers></configuration> 

2.在src下新建Role.java、RoleMapper.java、MybatisUtil.java、MainApp.java

Role.java

package com.lz.mybatis.model;public class Role {private Integer id;private String roleName;private String note;public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getRoleName() {return roleName;}public void setRoleName(String roleName) {this.roleName = roleName;}public String getNote() {return note;}public void setNote(String note) {this.note = note;}@Overridepublic String toString() {return "Role [id=" + id + ", roleName=" + roleName + ", note=" + note + "]";}}

RoleMapper.java

package com.lz.mybatis.mapper;import com.lz.mybatis.model.Role;public interface RoleMapper {Role getRole(Integer id);}

MybatisUtil.java

package com.lz.mybatis.util;import java.io.IOException;import java.io.InputStream;import org.apache.ibatis.io.Resources;import org.apache.ibatis.session.SqlSessionFactory;import org.apache.ibatis.session.SqlSessionFactoryBuilder;public class MybatisUtil {private static SqlSessionFactory sqlSessionFactory = null;public static SqlSessionFactory getSqlSessionFactory() {if (sqlSessionFactory == null) {String resource = "mybatis-config.xml";try {InputStream inputStream = Resources.getResourceAsStream(resource);sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);} catch (IOException e) {e.printStackTrace();return null;}}return sqlSessionFactory;}}

MainApp.java

package com.lz.mybatis.app;import org.apache.ibatis.session.SqlSession;import com.lz.mybatis.mapper.RoleMapper;import com.lz.mybatis.model.Role;import com.lz.mybatis.util.MybatisUtil;public class MainApp {public static void main(String[] args) {SqlSession session = null;try {session = MybatisUtil.getSqlSessionFactory().openSession();RoleMapper roleMapper = session.getMapper(RoleMapper.class);Role role = roleMapper.getRole(10001);System.out.println(role);} catch (Exception e) {e.printStackTrace();} finally {if (session != null) {session.close();}}}}

工程目录

运行程序，得到结果