Mybatis初学进行后台MySQL数据库增删改查

看了两天的MyBatis文档，尝试自己跟着文档一步步实现这个框架，步骤循序渐进。

一、原生开发模式

MySQL数据库先建一张user表，有username，birthday，sex，address这几个字段。

sqlMapConfig.xml核心配置文件，建立数据库连接，把User.xml通过mappers标签加进去

User.xml在这里面，用sql标签进行查询

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

User实体类

package com.itheima.mybatis.pojo;

import java.io.Serializable;
import java.util.Date;

public class User implements Serializable {
	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;
	private Integer id;
	private String username;// 
	private String sex;// 
	private Date birthday;// 
	private String address;// 


	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 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 + "]";
	}
}

编写一个抽象类，在这个抽象写一个加载SqlSessionFactory封装了一个实现的方法，返回sqlSession对象，便于获取该对象子类继承，另外一个写抽象方法。

package com.itheima.mybatis.junit;

import java.io.IOException;
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;

public abstract class MybatisFirst {//加载过程，写成抽象类的形式，子类继承
	
	
	public  SqlSession testMybatis() throws IOException{//抽象类里面的普通方法，创建sqlsession
		 
        String resource = "sqlMapConfig.xml";
		
		InputStream in = Resources.getResourceAsStream(resource);
		
		SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(in);
				
		SqlSession sqlSession = sqlSessionFactory.openSession();
		
		return sqlSession;
		
	}
	public abstract void TestMybatis() throws IOException ;
}

写一个子类作为测试类，通过super()继承该抽象类的SqlSession对象，进行具体的sqlsession.select()方法传参进行查询

package com.itheima.mybatis.junit;


import java.io.IOException;
import java.util.Date;
import java.util.List;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;
import com.itheima.mybatis.pojo.User;

/**
 * @author Administrator
 *
 */
public class MybatisFirstTest extends MybatisFirst{//子类，继承了父类的加载过程，把sqlSession通过super拿过来，用SqlSession对象接
		                                           //执行具体业务查询

	@Test
	public void TestMybatis () throws IOException {//该测试类，把mybatis核心配置引进，创建会话工厂SqlSessionFactory对象SqlSession，进行查询。
	    	
		SqlSession sqlSession = super.testMybatis();
		
		
        try {//查询一条记录
			List