项目结构
基础入门可参考：mybatis学习笔记(一）-- 简单入门（附测试Demo详细过程）
开始体验
1、新建项目，新建类MybatisUtil.java，路径：src/util/MybatisUtil.java
package util; import java.io.InputStream; import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder; public class MybatisUtil { /**
* 获取SqlSessionFactory
* @return SqlSessionFactory
*/
public static SqlSessionFactory getSqlSessionFactory() {
String resource = "conf.xml";
InputStream is = MybatisUtil.class.getClassLoader().getResourceAsStream(resource);
SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is);
return factory;
} /**
* 获取SqlSession
* @return SqlSession
*/
public static SqlSession getSqlSession() {
return getSqlSessionFactory().openSession();
} /**
* 获取SqlSession
* @param isAutoCommit
* true 表示创建的SqlSession对象在执行完SQL之后会自动提交事务
* false 表示创建的SqlSession对象在执行完SQL之后不会自动提交事务，这时就需要我们手动调用sqlSession.commit()提交事务
* @return SqlSession
*/
public static SqlSession getSqlSession(boolean isAutoCommit) {
return getSqlSessionFactory().openSession(isAutoCommit);
}
}
2、编写用户实体类User.java，路径：src/main/User.java
package main;
public class User {
private int id;
private String name;
private int age;
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 int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
}
3、编写mapper，以“新增用户”为示范案例
（1）基于xml实现，定义操作用户表的sql映射文件UserMapper.xml，路径：src/mapper/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="mapper.UserMapper"> <!-- 新增用户 -->
<insert id="addUser" parameterType="main.User">
insert into tb_user(name,age) values(#{name},#{age})
</insert> </mapper>
（2）基于注解实现，定义sql映射的接口，使用注解指明方法要执行的SQL，新建UserMapperI.java，路径：src/mapper/UserMapperI.java
package mapper; import java.util.List;
import main.User;
import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update; public interface UserMapperI { //使用@Insert注解指明add方法要执行的SQL
@Insert("insert into tb_user(name, age) values(#{name}, #{age})")
public int add(User user); }
4、添加配置文件，新建conf.xml文件，路径：src/conf.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>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC" />
<!-- 配置数据库连接信息 -->
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver" />
<property name="url" value="jdbc:mysql://localhost:3306/test" />
<property name="username" value="root" />
<property name="password" value="123456" />
</dataSource>
</environment>
</environments> <mappers>
<!-- 注册userMapper.xml文件(基于xml实现)-->
<mapper resource="mapper/userMapper.xml"/>
<!-- 注册UserMapper映射接口（基于注解实现）-->
<mapper class="mapper.UserMapperI"/>
</mappers> </configuration>
5、编写测试函数
（1）测试基于xml实现
public static void testAddByXmlMapper(){
//SqlSession sqlSession = MyBatisUtil.getSqlSession(false);
SqlSession sqlSession = MybatisUtil.getSqlSession(true);
String statement = "mapper.UserMapper.addUser";//映射sql的标识字符串
User user = new User();
user.setName("lucy");
user.setAge(22);
//执行插入操作
int retResult = sqlSession.insert(statement,user);
//手动提交事务
//sqlSession.commit();
//使用SqlSession执行完SQL之后需要关闭SqlSession
sqlSession.close();
System.out.println(retResult);
}
* 注解：
SqlSession sqlSession = MybatisUtil.getSqlSession(true);
true 表示创建的SqlSession对象在执行完SQL之后会自动提交事务
false 表示创建的SqlSession对象在执行完SQL之后不会自动提交事务，这时就需要我们手动调用sqlSession.commit()提交事务
（2）测试基于注解实现
public void testAddByAnnotationMapper() {
SqlSession sqlSession = MybatisUtil.getSqlSession(true);
// 得到UserMapperI接口的实现类对象，UserMapperI接口的实现类对象由sqlSession.getMapper(UserMapperI.class)动态构建出来
UserMapperI mapper = sqlSession.getMapper(UserMapperI.class);
User user = new User();
user.setName("tom");
user.setAge(20);
int add = mapper.add(user);
// 使用SqlSession执行完SQL之后需要关闭SqlSession
sqlSession.close();
System.out.println(add);
}
到此结束~ (@_@)以上...
