MyBatis框架（2019-09-23）

百度百科：https://baike.baidu.com/item/MyBatis/2824918?fr=aladdin

1.创建数据库

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2.创建数据库order表-执行语句

CREATE TABLE `order` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `user_id` int(11) NOT NULL COMMENT '下单用户id',
  `number` varchar(32) NOT NULL COMMENT '订单号',
  `createtime` date NOT NULL COMMENT '创建订单时间',
  `note` varchar(100) DEFAULT NULL COMMENT '备注',
  PRIMARY KEY (`id`),
  KEY `FK_orders_1` (`user_id`),
  CONSTRAINT `FK_order_id` FOREIGN KEY (`user_id`) REFERENCES `user` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION
) ENGINE=InnoDB AUTO_INCREMENT=6 DEFAULT CHARSET=utf8;

3.order表插入数据-执行语句

INSERT INTO `order` VALUES ('3', '1', '1000010', '2015-02-04 13:22:35', null);
INSERT INTO `order` VALUES ('4', '1', '1000011', '2015-02-03 13:22:41', null);
INSERT INTO `order` VALUES ('5', '10', '1000012', '2015-02-12 16:13:23', null);

4.创建数据库user表-执行语句

CREATE TABLE `user` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `username` varchar(32) NOT NULL COMMENT '用户名称',
  `birthday` date DEFAULT NULL COMMENT '生日',
  `sex` char(1) DEFAULT NULL COMMENT '性别',
  `address` varchar(256) DEFAULT NULL COMMENT '地址',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=27 DEFAULT CHARSET=utf8;

5.user表插入数据-执行语句

INSERT INTO `user` VALUES ('1', '王五', null, '2', null);
INSERT INTO `user` VALUES ('10', '张三', '2014-07-10', '1', '北京市');
INSERT INTO `user` VALUES ('16', '张小明', null, '1', '河南郑州');
INSERT INTO `user` VALUES ('22', '陈小明', null, '1', '河南郑州');
INSERT INTO `user` VALUES ('24', '张三丰', null, '1', '河南郑州');
INSERT INTO `user` VALUES ('25', '陈小明', null, '1', '河南郑州');
INSERT INTO `user` VALUES ('26', '王五', null, null, null);

6.数据库表执行结果

7.Eclipse中创建Maven工程

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8.添加compiler包

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9.编辑pom.xml配置文件

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10.创建model层User类

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User类

package com.neuedu.mybatis1.model;

import java.util.Date;

public class User {
        private int id;
        private String username;
        private Date birthday;
        private String sex;
        private String address;
        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 Date getBirthday() {
            return birthday;
        }
        public void setBirthday(Date birthday) {
            this.birthday = birthday;
        }
        public String getSex() {
            return sex;
        }
        public void setSex(String sex) {
            this.sex = sex;
        }
        public String getAddress() {
            return address;
        }
        public void setAddress(String address) {
            this.address = address;
        }
        @Override
        public String toString() {
            return "User [id=" + id + ", username=" + username + ", birthday=" + birthday + ", sex=" + sex
                    + ", address=" + address + "]";
        }       
}

11.增加mysql包

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12.创建SqlMapConfig.xml文件

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13.导入MyBatis包

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14.编辑SqlMapConfig.xml文件

15.创建config文件夹

config文件夹

16.创建log4j.properties日志文件

日志文件

17.编辑log4j.properties日志文件

# Global logging configuration 
log4j.rootLogger=DEBUG, stdout 
# Console output...
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n

日志文件

18.在config文件夹内创建UserMapper.xml文件

创建UserMapper.xml文件

19.编辑UserMapper.xml文件（重点）

• 查询方法
• 增加方法
• 删除方法
• 更新方法

    
    
        
        select * from user where id = #{id}
    
    
    
    
    
        
        
        
        select * from user where username like '%${value}%'
    
    
    
        
        insert into user values(null,#{username},#{birthday},#{sex},#{address})
    
    
    
    
        
        
        
            select max(id) from user
        
        
        insert into user values(null,#{username},#{birthday},#{sex},#{address})
    
    
    
    
        delete from user where id = #{id}
    
    
    
        update user set username=#{username},birthday=#{birthday},sex=#{sex},address=#{address} where id = #{id}
           

20.创建junit包

创建junit包

22.新建SessionFactoryUtil类

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23.编辑SessionFactoryUtil文件

• 重点:单例模式

package com.neuedu.mybatis1.utils;

import java.io.IOException;
import java.io.InputStream;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

public class SessionFactoryUtil {
    //SqlSessionFactory是一个单例模式
    //取得一个单例的SqlSessionFactory
    public static SqlSessionFactory sf = null;
    //静态代码块---加载类的时候执行的静态代码块
    static{
        SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
        InputStream is = null;
        try {
            is = Resources.getResourceAsStream("sqlMapConfig.xml");
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        sf = builder.build(is);
    }
    public static SqlSessionFactory getSqlSessionFactory(){
        return sf;  
    }   
}

24.创建junit类型的文件UTest

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25.编辑UTest文件

• 重点：方法名上方必须加@Test
• 创建SessionFactoryUtil文件之后，使用单例模式，在UTest里可以直接调用
• SqlSessionFactory factory = SessionFactoryUtil.getSqlSessionFactory();
• SqlSession sqlSession = factory.openSession();
• 注意最后需要进行提交事务和关闭
• sqlSession.commit(); 提交事务
• sqlSession.close();关闭

package test;
import java.io.IOException;
import java.util.Date;
import java.util.List;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.junit.Test;

import com.neuedu.mybatis1.model.User;
import com.neuedu.mybatis1.utils.SessionFactoryUtil;

public class UTest {

    @Test
    //保存测试用例：根据用户ID查询
    public void testGetById() throws IOException {
        SqlSessionFactory factory = SessionFactoryUtil.getSqlSessionFactory();
            //从工厂中创建连接
            SqlSession sqlSession = factory.openSession();
            User user = sqlSession.selectOne("user.getById",1);
            System.out.println(user);
            sqlSession.close();

}
    @Test
    public void testGetByUserName() throws IOException {
        SqlSessionFactory factory = SessionFactoryUtil.getSqlSessionFactory();
        //从工厂中创建连接
        SqlSession sqlSession = factory.openSession();
        List list = sqlSession.selectList("user.getByUserName","小");
        //关闭连接资源(放到连接池中)
        for(User u:list)
        System.out.println(u);
        sqlSession.close();
}
    
    @Test
    public void testsave() throws IOException {
        SqlSessionFactory factory = SessionFactoryUtil.getSqlSessionFactory();
        //从工厂中创建连接
        SqlSession sqlSession = factory.openSession();
        User user = new User();
        user.setUsername("小王");
        user.setBirthday(new Date());
        user.setSex("男");
        user.setAddress("辽宁铁岭");
        sqlSession.insert("user.save",user);
        //提交事务，默认是不提交       
        sqlSession.commit();
        System.out.println(user);
        sqlSession.close();
}
    
    @Test
    public void testsave2() throws IOException {
        SqlSessionFactory factory = SessionFactoryUtil.getSqlSessionFactory();
        //从工厂中创建连接
        SqlSession sqlSession = factory.openSession();
        User user = new User();
        user.setUsername("小王");
        user.setBirthday(new Date());
        user.setSex("男");
        user.setAddress("辽宁铁岭");
        sqlSession.insert("user.save2",user);       
        //提交事务，默认是不提交
        sqlSession.commit();
        System.out.println(user);
        sqlSession.close();
}
    @Test
    public void testdelete() throws IOException {
        SqlSessionFactory factory = SessionFactoryUtil.getSqlSessionFactory();
        SqlSession sqlSession = factory.openSession();
        sqlSession.delete("user.delete",43);
        sqlSession.commit();
        sqlSession.close();
}
    @Test
    public void testupdate() throws IOException {
        SqlSessionFactory factory = SessionFactoryUtil.getSqlSessionFactory();
        //从工厂中创建连接
        SqlSession sqlSession = factory.openSession();
        User user = sqlSession.selectOne("user.getById",24);
        user.setUsername("小李");
        user.setBirthday(new Date());
        user.setSex("男");
        user.setAddress("辽宁沈阳");
        sqlSession.update("user.update",user);      
        //提交事务，默认是不提交
        sqlSession.commit();
        sqlSession.close();
}
}

26.创建OrderMapper.xml文件，编辑OrderMapper.xml文件。创建OTest文件，编辑OTest文件。在SqlMapConfig.xml添加xml文件路径(原理同User)

• 注意：因为Order是在数据库中是关键字(Order by)，所以在进行查询数据库中的order表时，应该将order加上单引号，注意是键盘Tab键的上方的单引号
• OrderMapper.xml

    
    
    
        select * from `order` where id = #{id}
    
    
    
    
        select * from `order` where user_id = #{user_id}
    

    
    
        
            select max(id) from `order`
            
        insert into `order` values(null,#{user_id},#{number},#{createtime},#{note})
    
    
    
    
        delete from `order` where id = #{id}
    
    
    
        update `order` set user_id=#{user_id},number=#{number},createtime=#{createtime},note=#{note} where id = #{id}
           

• OTest

package test;

import java.io.IOException;
import java.util.Date;
import java.util.List;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.junit.Test;
import com.neuedu.mybatis1.model.Order;
import com.neuedu.mybatis1.utils.SessionFactoryUtil;

public class OTest {
    
    //增
    @Test
    public void insert() throws IOException{
        //1.调用uil
        SqlSessionFactory factory = SessionFactoryUtil.getSqlSessionFactory();
        //2.创建连接
        SqlSession sqlSession = factory.openSession();      
        //3.创建对象
        Order order = new Order();      
        //4.放入值
        order.setUser_id(10);
        order.setNumber("101101");
        order.setCreatetime(new Date());
        order.setNote("2544");
        //5.调用方法
        sqlSession.insert("or.insert",order);
        //6.提交
        sqlSession.commit();
        //7.关闭
        sqlSession.close();
    }
    
    //删
    @Test
    public void delete() throws IOException{
    SqlSessionFactory factory = SessionFactoryUtil.getSqlSessionFactory();
    SqlSession sqlSession = factory.openSession();
    sqlSession.delete("or.delete",3);
    sqlSession.commit();
    sqlSession.close(); 
    }
    
    //改
    @Test
    public void update() throws IOException{
    SqlSessionFactory factory = SessionFactoryUtil.getSqlSessionFactory();
    SqlSession sqlSession = factory.openSession();
    Order order = sqlSession.selectOne("or.select",4);
    order.setUser_id(26);
    order.setNumber("10145401");
    order.setCreatetime(new Date());
    order.setNote("2554");
    //5.调用方法
    sqlSession.update("or.update",order);
    //6.提交
    sqlSession.commit();
    //7.关闭
    sqlSession.close();
    }
    
    //查
    @Test
    public void select() throws IOException{
        SqlSessionFactory factory = SessionFactoryUtil.getSqlSessionFactory();
        SqlSession sqlSession = factory.openSession();
        Order order = sqlSession.selectOne("or.select",4);
        System.out.println(order);
        sqlSession.close(); 
        }
    
    @Test
    //根据user_id查集合
    public void selectList() throws IOException{
        SqlSessionFactory factory = SessionFactoryUtil.getSqlSessionFactory();
        SqlSession sqlSession = factory.openSession();
        List list = sqlSession.selectList("or.selectList",10);
        for(Order o:list){
        System.out.println(o);
        }
        sqlSession.close(); 
        }
    }

• 在SqlMapConfig.xml新增xml文件路径