MyBatis的CRUD
MyBatis的增删改查，特点是只要定义接口，不用实现方法，sql语句在xml中配置，非常方便
文件结构
接口UserDao
import com.jinke.domain.QueryVo;
import com.jinke.domain.User;
import java.util.List;
public interface UserDao {
List<User> findAll();
void saveUser(User user);
void updateUser(User user);
void deleteUser(Integer userId);
User findById(Integer userId);
List<User> findByName(String username);
int findTotal();
List<User> findUserByVo(QueryVo vo);
}
实体类User
import java.io.Serializable;
import java.util.Date;
public class User implements Serializable {
private Integer id;
private String username;
private String address;
private String sex;
private Date birthday;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", username='" + username + '\'' +
", address='" + address + '\'' +
", sex='" + sex + '\'' +
", birthday=" + birthday +
'}';
}
}
实体封装
public class QueryVo {
private User user;
public User getUser() {
return user;
}
public void setUser(User user) {
this.user = user;
}
}
SqlMapConfig.xml
<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE configuration
PUBLIC "-//mybatis.org//DTD Config 2.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<!--配置环境-->
<environments default="mysql">
<!--配置mysql的环境-->
<environment id="mysql">
<!--配置事务-->
<transactionManager type="JDBC"></transactionManager>
<!--配置连接池-->
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver"/>
<property name="url"
value="jdbc:mysql://localhost:3306/mybatis?useUnicode=true&characterEncoding=utf8"/>
<property name="username" value="root"/>
<property name="password" value="1234"/>
</dataSource>
</environment>
</environments>
<!--配置映射文件的位置-->
<mappers>
<mapper resource="com/jinke/dao/UserDao.xml"/>
</mappers>
</configuration>
sql语句
<?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.jinke.dao.UserDao">
<!--解决实体属性和表字段不一致的问题-->
<resultMap id="userMap" type="com.jinke.domain.User">
<id property="id" column="id"/>
<result property="username" column="username"/>
<result property="address" column="address"/>
<result property="sex" column="sex"/>
<result property="birthday" column="birthday"/>
</resultMap>
<select id="findAll" resultMap="userMap">
select * from user;
</select>
<!-- <select id="findAll" resultType="com.jinke.domain.User">
select * from user;
</select>-->
<insert id="saveUser" parameterType="com.jinke.domain.User">
/*配置插入操作后，获取插入数据的id*/
<selectKey keyProperty="id" keyColumn="id" resultType="int" order="AFTER">
select last_insert_id();
</selectKey>
insert into user(username,address,sex,birthday) values(#{username},#{address},#{sex},#{birthday});
</insert>
<update id="updateUser" parameterType="com.jinke.domain.User">
update user set username = #{username},address = #{address},sex = #{sex},birthday = #{birthday} where id = #{id};
</update>
<delete id="deleteUser" parameterType="Integer">
delete from user where id = #{uid};
</delete>
<select id="findById" parameterType="Integer" resultType="com.jinke.domain.User">
select * from user where id = #{uid};
</select>
<select id="findByName" parameterType="String" resultType="com.jinke.domain.User">
select * from user where username like #{name}
/*select * from user where username like '%${value}%'*/
</select>
<select id="findTotal" resultType="Integer">
select count(id) from user;
</select>
<!--查询类型封装-->
<select id="findUserByVo" parameterType="com.jinke.domain.QueryVo" resultType="com.jinke.domain.User">
select * from user where username like #{user.username}
</select>
</mapper>
测试类
import com.jinke.dao.UserDao;
import com.jinke.domain.QueryVo;
import com.jinke.domain.User;
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.After;
import org.junit.Before;
import org.junit.Test;
import java.io.InputStream;
import java.util.Date;
import java.util.List;
public class MyBatisTest {
private InputStream in;
private SqlSession sqlSession;
private UserDao userDao;
@Before
public void init() throws Exception {
in = Resources.getResourceAsStream("SqlMapConfig.xml");
SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
SqlSessionFactory factory = builder.build(in);
sqlSession = factory.openSession();
userDao = sqlSession.getMapper(UserDao.class);
}
@After
public void destroy() throws Exception {
sqlSession.commit();
sqlSession.close();
in.close();
}
@Test
public void testFindAll() {
List<User> users = userDao.findAll();
for (User user : users) {
System.out.println(user);
}
}
@Test
public void testSave() {
User user = new User();
user.setUsername("李四");
user.setAddress("上海");
user.setBirthday(new Date());
user.setSex("男");
userDao.saveUser(user);
}
@Test
public void testUpdate() {
User user = new User();
user.setId(2);
user.setUsername("王五");
user.setAddress("广州");
user.setBirthday(new Date());
user.setSex("男");
userDao.updateUser(user);
}
@Test
public void testDelete() {
userDao.deleteUser(2);
}
@Test
public void testFindOne() {
User user = userDao.findById(1);
System.out.println(user);
}
@Test
public void testFindByName() {
List<User> users = userDao.findByName("%张%");
for (User user : users) {
System.out.println(user);
}
}
@Test
public void testFindTotal() {
int total = userDao.findTotal();
System.out.println("total" + total);
}
@Test
public void testFindByVo() {
QueryVo vo = new QueryVo();
User user = new User();
user.setUsername("%张%");
vo.setUser(user);
List<User> users = userDao.findUserByVo(vo);
for (User u : users) {
System.out.println(u);
}
}
}
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