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