本文主要介绍了如何使用mybatis进行简单的数据库操作。本人使用的是mybatis3.05。
1.创建数据库表(User表)
CREATE TABLE `NewTable` (
`userId` bigint(20) NOT NULL AUTO_INCREMENT ,
`userName` varchar(30) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL ,
`password` varchar(80) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL ,
`comment` varchar(250) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL ,
PRIMARY KEY (`userId`),
UNIQUE INDEX `UQ_User_userName` (`userName`) USING BTREE
)
2.2. 创建实体类
package com.mybatis.config; public class User {
private int userId;
private String userName;
private String password;
private String comment;
public int getUserId() {
return userId;
}
public void setUserId(int userId) {
this.userId = userId;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getComment() {
return comment;
}
public void setComment(String comment) {
this.comment = comment;
}
}
3. 定义数据访问接口
package com.mybatis.config; import java.util.List; public interface UserDao { public int insert(User user); public int update(User user); public int delete(String userName); public List<User> selectAll(); public int countAll(); public User findByUserName(String userName);
}
4.创建MyBatis映射文件(UserDaoMapper.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="com.mybatis.config.UserDao">
<select id="countAll" resultType="int">
select count(*) c from user;
</select> <select id="selectAll" resultType="com.mybatis.config.User">
select * from user order by userName asc
</select> <insert id="insert" parameterType="com.mybatis.config.User">
insert into user(userName,password,comment) values(#{userName},#{password},#{comment})
</insert> <update id="update" parameterType="com.mybatis.config.User">
update user set userName=#{userName},password=#{password},comment=#{comment} where userName=#{userName}
</update> <delete id="delete" parameterType="int">
delete from user where userName=#{userName}
</delete> <select id="findByUserName" parameterType="String" resultType="com.mybatis.config.User">
select * from user where userName=#{userName}
</select>
</mapper>
5. 创建mybatis配置文件
<?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" />
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver" />
<property name="url" value="jdbc:mysql://localhost:3306/hlp?useUnicode=true&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull" />
<property name="username" value="root" />
<property name="password" value="1234" />
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="com/mybatis/config/UserDaoMapper.xml"/>
</mappers>
</configuration>
6. 编写测试代码
package com.mybatis.config; import java.io.Reader;
import java.util.Iterator;
import java.util.List;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Test; public class UserDaoTest {
@Test
public void userDaoTest() throws Exception
{
String resource = "MyBatis-Configuration.xml";
Reader reader = Resources.getResourceAsReader(resource);
SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
SqlSessionFactory factory = builder.build(reader); SqlSession session = factory.openSession();
UserDao userDao = session.getMapper(UserDao.class); User user = new User();
user.setUserName("hongye");
user.setPassword("123456");
user.setComment("备注"); userDao.insert(user);
System.out.println("记录条数:"+userDao.countAll()); List<User> users = userDao.selectAll();
Iterator<User> iter = users.iterator();
while(iter.hasNext()){
User u = iter.next();
System.out.println("用户名:"+u.getUserName()+"密码:"+u.getPassword());
} user.setComment("comment");
userDao.update(user);
User u = userDao.findByUserName("hongye");
System.out.println(u.getComment()); userDao.delete("hongye");
System.out.println("记录条数:"+userDao.countAll()); session.commit();
session.close();
}
}