工具：MyEclipse
jar包：mybatis-3.4.4.jar,mysql-connector-java-5.1.7.bin.jar
项目目录：
步骤
一.新建数据源：jdbc.properties
driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/test
username=root
password=mysql
二.新建Mybatis配置文件：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"></properties>
<typeAliases>
<typeAlias alias="User" type="mybatis.model.User"/>
</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="username" value="${username}"/>
<property name="password" value="${password}"/>
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="mapper/UserMapper.xml"/>
</mappers>
</configuration>
typeAliases类型别名是Java 类型的简称。 它仅仅只是关联到XML 配置，简写冗长的JAVA 类名。例如：
mappers这里是告诉MyBatis 去哪寻找映射SQL 的语句。可以使用类路径中的资源引用，或者使用字符，输入确切的URL 引用，若不明白请继续看下文.
三.新建Model(POJO)(不必照搬，可自行对照数据库中的表)
package mybatis.model;
public class User {
private int id;
private String name;
private String password;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
四.新建Dao
package mybaits.dao;
import mybatis.model.User;
public interface UserDao {
public User getById(int id);
}
五.新建Mapper.xml
先在src目录中新建一个mapper文件夹
新建一个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">
<mapper namespace="mybaits.dao.UserDao">
<select id="getById" parameterType="int" resultType="User">
select * from user where id=#{id}
</select>
</mapper>
namesapce为mapper对应的类
id为所调用的方法parameterType属性为传入的参数类型returnType为返回类型，如果前面mybatis-config.xml中的typeAliases没有写，就得写为 mybatis.model.User，这可以写User就是起别名的好处#{id}即读取传入的id值
六.创建SqlSessionFactoryUtil来读取配置文件和获取Session
package mybatis.util;
import java.io.IOException;
import java.io.InputStream;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
public class SqlSessionFactoryUtil {
public static SqlSessionFactory sqlSessionFactory;
public static SqlSessionFactory getSqlSessionFactory(){
if(sqlSessionFactory==null){
InputStream inputStream = null;
try {
//读取配置文件
inputStream = Resources.getResourceAsStream("mybatis-config.xml");
//创建SqlSessionFactory
sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
} catch (IOException e) {
e.printStackTrace();
}
}
return sqlSessionFactory;
}
public static SqlSession openSession(){
return getSqlSessionFactory().openSession();
}
}
七.运行
package mybatis.main;
import org.apache.ibatis.session.SqlSession;
import mybaits.dao.UserDao;
import mybatis.model.User;
import mybatis.util.SqlSessionFactoryUtil;
public class Main {
public static void main(String[] args) {
SqlSession session = SqlSessionFactoryUtil.openSession();
UserDao userDao = session.getMapper(UserDao.class);
User user = userDao.getById(1);
System.out.println("Hello!"+user.getName());
}
}
