mybatis入门案例(一)

迷南。 2022-06-12 14:27 302阅读 0赞

所需jar包  
![这里写图片描述][SouthEast]

项目目录  
![这里写图片描述][SouthEast 1]  
SqlMapConfig.xml配置

<?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"></transactionManager>
                
                <dataSource type="POOLED">
                    <property name="driver" value="com.mysql.jdbc.Driver" />
                    <property name="url" value="jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf8" />
                    <property name="username" value="root" />
                    <property name="password" value="root" />
                </dataSource>
            </environment>
        </environments>
    
        
        <mappers>
            <mapper resource="User.xml" />
    
            
    
        </mappers>
    </configuration>

User.xml配置

<?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="test">
        
        
        
        
        
        
        
        <select id="findUserById" parameterType="int" resultType="com.test.domain.User">
            SELECT * FROM USER WHERE id =#{id}
        </select>
    </mapper>

实体类

package com.test.domain;
    
    import java.util.Date;
    
    public class User { 
        private int id;
        private String username;// 用户姓名
        private String sex;// 性别
        private Date birthday;// 生日
        private String address;// 地址
    
        public int getId() {
            return id;
        }
        public void setId(int id) {
            this.id = id;
        }
        public String getUsername() {
            return username;
        }
        public void setUsername(String username) {
            this.username = username;
        }
        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;
        }
        public String getAddress() {
            return address;
        }
        public void setAddress(String address) {
            this.address = address;
        }
        @Override
        public String toString() {
            return "User [id=" + id + ", username=" + username + ", sex=" + sex
                    + ", birthday=" + birthday + ", address=" + address + "]";
        }
    
    }

测试类

package com.test.test;
    
    import java.io.InputStream;
    
    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 com.test.domain.User;
    
    public class Test {
        @org.junit.Test
        public void findUserByIdTest() throws Exception{
            //读取配置文件
            //全局配置文件的路径
            String resource = "SqlMapConfig.xml";
            InputStream inputStream = Resources.getResourceAsStream(resource);
    
            //创建SqlSessionFactory
            SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
    
            //创建SqlSession
            SqlSession sqlSession = sqlSessionFactory.openSession();
    
            //调用SqlSession的增删改查方法
            //第一个参数：表示statement的唯一标示
            User user = sqlSession.selectOne("test.findUserById", 1);
            System.out.println(user);
    
            //关闭资源
            sqlSession.close();
        }
    }

运行结果  
User \[id=1, username=王五, sex=2, birthday=null, address=null\]

[SouthEast]: /images/20220612/72a579ebde1a40fda0479fcd509200c1.png
[SouthEast 1]: /images/20220612/c88eb20b49594c039aab122e8dfe3049.png