Java中使用Mybatis操作数据库主要有两种方法：注解和xml配置，注解相对比较简单和方便，两种方式的效果一致。本文以注解的方式说明用Mybatis访问数据库的方法
一、创建数据表(MySql)
| 1 2 3 4 5 6 7 8 9 | -- ---------------------------- -- Table structure for admininfo -- ---------------------------- DROP TABLE IF EXISTS `admininfo`; CREATE TABLE `admininfo` ( `ID` int (11) NOT NULL AUTO_INCREMENT, `AdminName` varchar (20) NOT NULL , PRIMARY KEY (`ID`) ) ENGINE=InnoDB AUTO_INCREMENT=25 DEFAULT CHARSET=latin1; |
二、创建mybatis的配置文件：mybatisConf.xml，由于使用maven进行管理，所以放在java–>resources文件夹下，其它位置也可以，只有最终在\target\classes\mybatisConf.xml生成文件即可
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 | <? 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://127.0.0.1/test" /> < property name = "username" value = "root" /> < property name = "password" value = "root" /> </ dataSource > </ environment > </ environments > < mappers > <!-- 注册映射接口，该接口文件包含了数据访问方法和SQL --> < mapper class = "dal.dataaccess.IAdminInfoMapper" /> </ mappers > </ configuration > |
三、创建IAdminInfoMapper文件（本文中包名为dal.dataaccess)
该接口的功能主要是提供对AdminInfo表的数据操作
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 | package dal.dataaccess; import java.util.List; import org.apache.ibatis.annotations.Delete; import org.apache.ibatis.annotations.Insert; import org.apache.ibatis.annotations.Select; import org.apache.ibatis.annotations.Update; import dal.beans.AdminInfo; import dal.beans.AdminRightInfo; public interface IAdminInfoMapper { //使用@Select注解指明getById方法要执行的SQL @Select ( "select * from admininfo where id=#{id}" ) public AdminInfo getById( int id); //使用@Select注解指明getAll方法要执行的SQL @Select ( "select * from admininfo" ) public List<AdminInfo> getAll(); //使用@Insert注解指明add方法要执行的SQL @Insert ( "insert into admininfo(adminName) values(#{adminName})" ) public int add(AdminInfo user); //使用@Update注解指明update方法要执行的SQL @Update ( "update admininfo set adminName=#{adminName} where id=#{id}" ) public int update(AdminInfo user); //使用@Delete注解指明deleteById方法要执行的SQL @Delete ( "delete from admininfo where id=#{id}" ) public int deleteById( int id); } |
四、定义操作数据库的公共方法
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 | package framework.utils; 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 = "mybatisConf.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); } } |
五、对adminInfo表进行增删改查
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 | package test; import java.util.List; import org.apache.ibatis.session.SqlSession; import org.junit.Test; import dal.beans.*; import framework.utils.MyBatisUtil; import dal.dataaccess.*; public class MybatisAnnotationTest { // http://www.cnblogs.com/xdp-gacl/p/4261895.html @Test public void Select() { SqlSession sqlSession = MyBatisUtil.getSqlSession(); // 得到AdminInfoMapper接口的实现类对象，IAdminInfoMapper接口的实现类对象由sqlSession.getMapper(IAdminInfoMapper.class)动态构建出来 IAdminInfoMapper mapper = sqlSession.getMapper(IAdminInfoMapper. class ); // 执行查询操作，将查询结果自动封装成User返回 AdminInfo bean = mapper.getById( 13 ); // 使用SqlSession执行完SQL之后需要关闭SqlSession sqlSession.close(); System.out.println(bean.getId()); System.out.println(bean.getAdminName()); } @Test public void SelectAll() { SqlSession sqlSession = MyBatisUtil.getSqlSession(); IAdminInfoMapper mapper = sqlSession.getMapper(IAdminInfoMapper. class ); List<AdminInfo> bean = mapper.getAll(); sqlSession.close(); System.out.println(bean.size()); } @Test public void Insert() { SqlSession sqlSession = MyBatisUtil.getSqlSession(); IAdminInfoMapper mapper = sqlSession.getMapper(IAdminInfoMapper. class ); AdminInfo bean = new AdminInfo(); bean.setAdminName( "Admin" + System.currentTimeMillis()); int result = mapper.add(bean); sqlSession.commit(); sqlSession.close(); System.out.println(result); } @Test public void Update() { SqlSession sqlSession = MyBatisUtil.getSqlSession(); IAdminInfoMapper mapper = sqlSession.getMapper(IAdminInfoMapper. class ); AdminInfo bean = new AdminInfo(); bean.setId( 12 ); bean.setAdminName( "Admin" + System.currentTimeMillis()); int result = mapper.update(bean); sqlSession.commit(); sqlSession.close(); System.out.println(result); } @Test public void Delete() { SqlSession sqlSession = MyBatisUtil.getSqlSession(); IAdminInfoMapper mapper = sqlSession.getMapper(IAdminInfoMapper. class ); int result = mapper.deleteById( 12 ); sqlSession.commit(); sqlSession.close(); System.out.println(result); } } |
六、由于使用了maven进行依赖管理，pom.xml还需要添加
| 1 2 3 4 5 6 7 8 9 10 | < dependency > < groupId >mysql</ groupId > < artifactId >mysql-connector-java</ artifactId > < version >5.1.38</ version > </ dependency > < dependency > < groupId >org.mybatis</ groupId > < artifactId >mybatis</ artifactId > < version >3.3.0</ version > </ dependency > |
