基本步骤:
- 加入jar包
- 定义dao接口
- 定义配置文件
- 实现dao接口
快速示例
环境
mysql数据库,已经表user,内有字段id,name,mark,其中id为主键,并且是自动递增类型
CREATE TABLE `user` ( `id` int(11) NOT NULL AUTO_INCREMENT, `name` varchar(20) DEFAULT NULL, `mark` varchar(100) DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8;
1.所需JAR包
mybatis-3.0.5.jar
2.对象实体类 User.java 包路径testMybatis.user
package testMybatis.user; public class User { Long id; String name; String mark; public Long getId() { return id; } public void setId(Long id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getMark() { return mark; } public void setMark(String mark) { this.mark = mark; } @Override public String toString() { return "User [id=" + id + ", name=" + name + ", mark=" + mark + "]"; } }
3.DAO层接口类 TestDao.java 包路径testMybatis.user
package testMybatis.user; public interface TestDao { public int insert(User user); public User select(long id); public List<User> selectAll(); public int delete(long id); }
4.定义配置文件
(注意:文件位置与接口在同一位置,文件名与接口同名,后缀以.xml结尾)
示例文件TestDao.xml 位置 testMybatis.user;
<?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="testMybatis.user.TestDao"> <insert id="insert" parameterType="testMybatis.user.User" useGeneratedKeys="true" keyProperty="id"> insert into user (name,mark) values (#{name},#{mark}) </insert> <select id="select" parameterType="long" resultType="testMybatis.user.User"> select * from user where name.id=#{id} </select> <select id="selectAll" resultType="testMybatis.user.User" > select * from user </select> <delete id="delete" parameterType="long"> delete from user where id = #{id} </delete> </mapper>
5.实现类TestDaoImp.java
(注意:本示例为快速测试使用的是编码配置数据源工厂,一般使用文件配置)
package testMybatis.user; import java.util.List; /** * @author DingFengHua * @since Apr 16, 2012 */ public class TestDaoImp implements TestDao { //当前用于快速测试,一般设计成单例使用工具类来调用 static SqlSessionFactory sqlSessionFactory; static { DataSource dataSource = new PooledDataSource("com.mysql.jdbc.Driver", "jdbc:mysql://localhost/mybatis?userUnicode=true&characterEncoding=utf8", "admin", "123456"); Environment environment = new Environment("test", new JdbcTransactionFactory(), dataSource); Configuration configuration = new Configuration(environment); configuration.addMapper(TestDao.class); sqlSessionFactory = new SqlSessionFactoryBuilder().build(configuration); } /* * (non-Javadoc) * @see testMybatis.user.testDao#insertName(testMybatis.user.User) */ @Override public int insert(User user) { SqlSession session = sqlSessionFactory.openSession(); int num = 0; try { TestDao dao = session.getMapper(TestDao.class); num = dao.insert(user); session.commit(); } finally { session.close(); } return num; } /* * (non-Javadoc) * @see testMybatis.user.testDao#select(long) */ @Override public User select(long id) { SqlSession session = sqlSessionFactory.openSession(); try { TestDao dao = session.getMapper(TestDao.class); return dao.select(id); } finally { session.close(); } } /* * (non-Javadoc) * @see testMybatis.user.testDao#delete(long) */ @Override public int delete(long id) { SqlSession session = sqlSessionFactory.openSession(); try { TestDao dao = session.getMapper(TestDao.class); int num = dao.delete(id); session.commit(); return num; } finally { session.close(); } } /* (non-Javadoc) * @see testMybatis.user.testDao#selectAll() */ @Override public List<User> selectAll() { SqlSession session = sqlSessionFactory.openSession(); try { TestDao dao = session.getMapper(TestDao.class); return dao.selectAll(); } finally { session.close(); } } }
6.测试
public class Main { public static void main(String... a) { TestDao main = new TestDaoImp(); User user = new User(); user.setName("name1"); user.setMark("no mark"); System.out.println(main.insert(user)); //System.out.println(main.delete(1l)); for (User u : main.selectAll()) { System.out.println(u); } } }
完成