第一次MyBatis连接数据库mysql测试（Spring+Mybatis idea软件）

部署项目结构

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• 配置mybatis-config.xml文件（这里都要配置在资源文件下，才能够被解析）

• mybatis-config.xml

  <?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>
  <settings>
      <setting name="logImpl" value="LOG4J"/>
  </settings>
      <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://127.0.0.1:3306/mybatis?characterEncoding=utf-8"/>
                  <property name="username" value="root"/>
                  <property name="password" value="数据库密码"/>
              </dataSource>
          </environment>
      </environments>
      <mappers>
          <mapper resource="UserMapper.xml"/>
      </mappers>
  </configuration>

• log4j.properties

• log4j.rootLogger=ERROR, stdout
  log4j.logger.com.ssm.mapper.UserMapper=DEBUG
  log4j.appender.stdout=org.apache.log4j.ConsoleAppender
  lo4j.appender.stdout.layout=org.apache.log4j.PatternLayout
  log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n

• UserMapper.xml（一定要记得放在resource文件下,不然出错了找好久都没法找到错误的地方！）
  ​​​​​​​<?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.ssm.mapper.UserMapper">
  <insert id="save" useGeneratedKeys="true" parameterType="com.ssm.web.model.User" >
      INSERT INTO TB_USER(name,sex,age) values (#{name},#{sex},#{age})
  </insert>
      <update id="up" useGeneratedKeys="true" parameterType="com.ssm.web.model.User">
          update tb_user set name=#{name},sex=#{sex},age=#{age} where id=#{id}
      </update>

  <select id="selectUserById" parameterType="Integer" resultType="com.ssm.web.model.MyUser">
      select * from user where uid=#{uid}
  </select>
      <select id="selectAllUser" resultType="com.ssm.web.model.MyUser">
          select * from user
      </select>
      <insert id="addUser" parameterType="com.ssm.web.model.MyUser">
          insert into user (uname,usex) values (#{uname},#{usex})
      </insert>
      <update id="updateUser" parameterType="com.ssm.web.model.MyUser">
          update user set uname =#{uname},usex=#{usex} where uid=#{uid}
      </update>
      <delete id="deleteUser" parameterType="com.ssm.web.model.MyUser">
          delete from user where uid=#{uid}
      </delete>
  </mapper>

• package com.ssm.web.model;
  
  public class MyUser {
      private Integer uid;
      private String uname;
      private String usex;
  
      @Override
      public String toString() {
          return "MyUser{" +
                  "uid=" + uid +
                  ", uname='" + uname + '\'' +
                  ", usex='" + usex + '\'' +
                  '}';
      }
  
      public Integer getUid() {
          return uid;
      }
  
      public void setUid(Integer uid) {
          this.uid = uid;
      }
  
      public String getUname() {
          return uname;
      }
  
      public void setUname(String uname) {
          this.uname = uname;
      }
  
      public String getUsex() {
          return usex;
      }
  
      public void setUsex(String usex) {
          this.usex = usex;
      }
  }
  

• package com.ssm.Test;
  
  import com.ssm.web.model.MyUser;
  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 java.io.IOException;
  import java.io.InputStream;
  import java.util.List;
  
  public class MyBatisTest2 {
      public static void main(String[]args){
          try {
              InputStream config= Resources.getResourceAsStream("mybatis-config.xml");
              SqlSessionFactory ssf=new SqlSessionFactoryBuilder().build(config);
              SqlSession ss=ssf.openSession();
              MyUser mu=ss.selectOne("com.ssm.mapper.UserMapper.selectUserById",1);
              System.out.println(mu);
              MyUser addmu=new MyUser();
              addmu.setUname("dgd");
              addmu.setUsex("nan");
              ss.insert("com.ssm.mapper.UserMapper.addUser",addmu);
              MyUser updatemu=new MyUser();
              updatemu.setUid(1);
              updatemu.setUname("张");
              updatemu.setUsex("女");
              ss.update("com.ssm.mapper.UserMapper.updateUser",updatemu);
              ss.delete("com.ssm.mapper.UserMapper.deleteUser",3);
              List<MyUser>list=ss.selectList("com.ssm.mapper.UserMapper.selectAllUser");
              for (MyUser myUser:list){
                  System.out.println(myUser);
              }
              ss.commit();
              ss.close();
          }catch (IOException e){
              e.printStackTrace();
          }
      }
  }

运行结果（随意自己怎么输数据）能运行出来就可以看到后台的数据库的数据变化了。