public class MyBatisDBUtil {//SqlSession//工厂模式private static SqlSessionFactory sqlSessionFactory; //以一个 SqlSessionFactory 的实例为中心的public static void main (String[] args) {  //测试连接数据库是否成功System.out.println(getSqlSession());}public static SqlSession getSqlSession() {if(sqlSessionFactory == null) {sqlSessionFactory = getSqlSessionFactory();}SqlSession sqlSession = sqlSessionFactory.openSession();return sqlSession;}public static SqlSessionFactory getSqlSessionFactory() { //SqlSessionFactory 的实例可以通过 SqlSessionFactoryBuilder 获得String configPath = "conf/mybatis-config.xml"; try {InputStream in = Resources.getResourceAsStream(configPath);//输入流(InputStream)sqlSessionFactory = new SqlSessionFactoryBuilder().build(in);//SqlSessionFactory 的实例可以通过 SqlSessionFactoryBuilder 获得} catch (IOException e) {e.printStackTrace();}return sqlSessionFactory;}
}

public class Girl {private String name;private Integer age;private Date birth; public Girl() {super();}public Girl(String name, Integer age, Date birth) {super();this.name = name;this.age = age;this.birth = birth;}public String getName() {return name;}public void setName(String name) {this.name = name;}public Integer getAge() {return age;}public void setAge(Integer age) {this.age = age;}public Date getBirth() {return birth;}public void setBirth(Date birth) {this.birth = birth;}@Overridepublic String toString() {return "Girl [name=" + name + ", age=" + age + ", birth=" + birth + "]";}}

jdbc.username=TEST
jdbc.password=TEST
jdbc.ClassName=oracle.jdbc.OracleDriver
jdbc.url=jdbc:oracle:thin:@localhost:1521:orcl

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configurationPUBLIC "-//mybatis.org//DTD Config 3.0//EN""http://mybatis.org/dtd/mybatis-3-config.dtd ">
<configuration>   <!-- XML 配置文件（configuration XML）中包含了对 MyBatis 系统的核心设置 --><!-- 获取属性文件 --><properties resource="conf/jdbc_orcl.properties"></properties><!-- 类型别名, 为实体类定义一个别名 --><typeAliases><package name="model"/>  <!-- 包名,在映射的XML文件里面的resultType直接写类名即可 -->  </typeAliases><environments default="test"><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><!-- 使用属性文件里面的值, --><environment id="test"><transactionManager type="JDBC"/><dataSource type="POOLED"><property name="driver" value="${jdbc.ClassName}"/>  <property name="url" value="${jdbc.url}"/> <property name="username" value="${jdbc.username}"/>  <property name="password" value="${jdbc.password}"/></dataSource></environment></environments><mappers> <!-- mappers 元素则是包含一组 mapper 映射器（这些 mapper 的 XML 文件包含了 SQL 代码和映射定义信息),引入映射文件, 引入方式有四种:url, class, resource, package --><mapper resource="mapper/GirlMapper.xml"/> <!-- 直接扫描的是映射文件本身 --></mappers></configuration>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="mapper.GirlMapper">  <!-- 映射的SQL语句 --><!--  <insert id="addGirl" parameterType="model.Girl">  表示的是参数类型,model下面的实体类,里面的变量直接进入insert into girl values(#{name},#{age})  这里面获取的名字是跟Girl实体类里面的名称是相对应的</insert> --><!--  查询表中所有数据 --><select id="selectGirls" resultType="Girl">  <!-- 直接写那个类名就好,此处写的id名称为映射接口里面定义的方法名-->select * from girl   </select><!-- 条件查询,根据年龄查找 --><select id="selectGirl2" resultType="Girl">select * from girl g where g.age = #{param1} </select><!-- 条件删除 --><delete id="deleteGirl" parameterType="String">delete  girl g where g.name = #{param1}</delete><!-- 添加数据 --><insert id="insertGirl" parameterType="map">insert into girl values(#{girl_name},#{girl_age},to_date(#{girl_birth},'yyyy-mm-dd'))</insert><!--  修改数据 --><update id="updateGirl" parameterType="Integer">update girl g set g.name = '王大娘' where g.age = #{param1}</update>
</mapper>

public interface GirlMapper {  //接口的名字要与xml里面的名字相同,这里面的方法不允许重载List<Girl> selectGirls(); //查找全表List<Girl> selectGirl2(Integer age);  //根据年龄查询int deleteGirl(String name); //根据姓名删除int insertGirl(Map<String,Object> map); //插入数据int updateGirl(Integer age); //更新数据
}

class JTest {  //单元测试框架private SqlSession sqlSession;private GirlMapper gm;void test() {  //查询表的全部List<Girl> list = gm.selectGirls();for (Girl g : list) {System.out.println(g);}}void test2() {  //根据年龄查询List<Girl> list = gm.selectGirl2(20);for (Girl g : list) {System.out.println(g);}}void test3() {  //根据姓名删除int i =  gm.deleteGirl("小孩");System.out.println(i);}void test4() {  //添加数据Map<String,Object> map = new HashMap<String,Object>();map.put("girl_name", "哈哈");map.put("girl_age", 21);map.put("girl_birth","1993-11-24");int i = gm.insertGirl(map);System.out.println(i);}@Testvoid test5() {  //根据年龄更新数据int i =  gm.updateGirl(20);System.out.println(i);}@BeforeEachvoid setUp() throws Exception {sqlSession = MyBatisDBUtil.getSqlSession();  //调用until包下面的MybatisDBUtil类里面的getSqlSession方法gm = sqlSession.getMapper(GirlMapper.class); //sqlSession先把映射的文件和接口放进一个集合里面,找到映射接口的路径}@AfterEachvoid tearDown() throws Exception {    sqlSession.commit();  //提交sqlSession.close();   //关闭}}