Mybatis入门使用XML

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原创最新推荐文章于 2026-04-04 03:00:33 发布 933 阅读 AI 写同款· GEO 优化 ›

入门MyBatis的XML配置文件关于入门MyBatis的配置文件，XML头部声明、类型别名、开发环境配置、事务管理器、配置数据源、映射器、mapper的命名空间、crud、参数、缓存。阅读详情

1、项目结构

在这里插入图片描述

2、详细代码

数据库：
在这里插入图片描述

1、创建实体类bean

package com.itheima.domain;

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

/**
 * Created by Administrator on 2019/10/11.
 */
public class User implements Serializable {
    private Integer id;
    private String username;
    private Date birthday;
    private String sex;
    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 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 + '\'' +
                '}';
    }
}

2、查找数据库中所有用户的Dao

package com.itheima.dao;

import com.itheima.domain.User;

import java.util.List;

/**
 * Created by Administrator on 2019/10/11.
 * 用户持久层接口
 */
public interface IUserDao {
    /**
     * 查询所有操作
     * @return
     */
    List<User>  findAll();
}

3、配置文件

<?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">
<!--mybatis的主配主文件-->
<configuration>
<!--配置环境-->
<environments default="mysql">
    <!--配置MySQL环境变量-->
    <environment id="mysql">
        <!--配置事物的类型-->
        <transactionManager type="JDBC"></transactionManager>
        <!--配置数据源（连接池）-->
        <dataSource type="POOLED">
            <!--配置链接数据库的四个基本信息-->
            <property name="driver" value="com.mysql.jdbc.Driver"></property>
            <property name="url" value="jdbc:mysql://localhost:3306/eesy_mybatis"></property>
            <property name="username" value="root"></property>
            <property name="password" value="123456"></property>
        </dataSource>
    </environment>
</environments>
    <!--指定映射配置文件的位置，映射配置文件指的是每个dao独立的配置文件-->
    <mappers>
        <mapper resource="com/itheima/dao/IUserDao.xml"/>
    </mappers>
</configuration>

5、dao层对用的mapper映射文件

<?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.itheima.dao.IUserDao">
  <!--查询所有-->
    <select id="findAll" resultType="com.itheima.domain.User">
      SELECT * FROM user;
    </select>
</mapper>

6、 log4j.properties 直接导入，无需修改。日志配置

# Set root category priority to INFO and its only appender to CONSOLE.
#log4j.rootCategory=INFO, CONSOLE            debug   info   warn error fatal
log4j.rootCategory=debug, CONSOLE, LOGFILE

# Set the enterprise logger category to FATAL and its only appender to CONSOLE.
log4j.logger.org.apache.axis.enterprise=FATAL, CONSOLE

# CONSOLE is set to be a ConsoleAppender using a PatternLayout.
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n

# LOGFILE is set to be a File appender using a PatternLayout.
log4j.appender.LOGFILE=org.apache.log4j.FileAppender
log4j.appender.LOGFILE.File=d:\axis.log
log4j.appender.LOGFILE.Append=true
log4j.appender.LOGFILE.layout=org.apache.log4j.PatternLayout
log4j.appender.LOGFILE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n

7、test单元测试

package com.itheima.test;


import com.itheima.dao.IUserDao;
import com.itheima.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 java.io.IOException;
import java.io.InputStream;
import java.util.List;

/**
 * Created by Administrator on 2019/10/12.
 */
public class Mybatis {
    /**
     * 入门案例
     *
     * @param args
     */
    public static void main(String[] args) throws Exception {
//   1、 读取配置文件
        InputStream in = Resources.getResourceAsStream("SqlMapConfig.xml");
//   2、创建SqlSessionFactory工厂
        SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
        SqlSessionFactory factory =builder.build(in);
//   3、使用工厂生产SqlSession对象
        SqlSession session = factory.openSession();
//   4、使用SqlSession创建Dao接口的代理对象
        IUserDao userDao = session.getMapper(IUserDao.class);
//   5、使用代理对象执行方法
        List<User> users = userDao.findAll();
        for (User user :users){
            System.out.println(user);
        }
//   6、释放资源
        session.close();
        in.close();
    }
}

8、输出结果

"C:\Program Files\Java\jdk1.8.0_131\bin\java" -Didea.launcher.port=7533 "-Didea.launcher.bin.path=D:\IntelliJ IDEA 14.0.2\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files\Java\jdk1.8.0_131\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\rt.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_131\jre\lib\ext\zipfs.jar;D:\IDEA项目\itheima_mybatis_day01_01\target\test-classes;D:\IDEA项目\itheima_mybatis_day01_01\target\classes;D:\ruanjian\meaven\apache-maven-3.6.2-bin\repository\org\mybatis\mybatis\3.4.5\mybatis-3.4.5.jar;D:\ruanjian\meaven\apache-maven-3.6.2-bin\repository\mysql\mysql-connector-java\5.1.6\mysql-connector-java-5.1.6.jar;D:\ruanjian\meaven\apache-maven-3.6.2-bin\repository\log4j\log4j\1.2.17\log4j-1.2.17.jar;D:\ruanjian\meaven\apache-maven-3.6.2-bin\repository\junit\junit\4.11\junit-4.11.jar;D:\ruanjian\meaven\apache-maven-3.6.2-bin\repository\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar;D:\IntelliJ IDEA 14.0.2\lib\idea_rt.jar" com.intellij.rt.execution.application.AppMain com.itheima.test.Mybatis
2019-10-12 22:31:22,500 0      [           main] DEBUG ache.ibatis.logging.LogFactory  - Logging initialized using 'class org.apache.ibatis.logging.log4j.Log4jImpl' adapter.
2019-10-12 22:31:22,636 136    [           main] DEBUG source.pooled.PooledDataSource  - PooledDataSource forcefully closed/removed all connections.
2019-10-12 22:31:22,637 137    [           main] DEBUG source.pooled.PooledDataSource  - PooledDataSource forcefully closed/removed all connections.
2019-10-12 22:31:22,637 137    [           main] DEBUG source.pooled.PooledDataSource  - PooledDataSource forcefully closed/removed all connections.
2019-10-12 22:31:22,637 137    [           main] DEBUG source.pooled.PooledDataSource  - PooledDataSource forcefully closed/removed all connections.
2019-10-12 22:31:22,744 244    [           main] DEBUG ansaction.jdbc.JdbcTransaction  - Opening JDBC Connection
2019-10-12 22:31:22,922 422    [           main] DEBUG source.pooled.PooledDataSource  - Created connection 343965883.
2019-10-12 22:31:22,922 422    [           main] DEBUG ansaction.jdbc.JdbcTransaction  - Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@148080bb]
2019-10-12 22:31:22,924 424    [           main] DEBUG m.itheima.dao.IUserDao.findAll  - ==>  Preparing: SELECT * FROM user; 
2019-10-12 22:31:22,963 463    [           main] DEBUG m.itheima.dao.IUserDao.findAll  - ==> Parameters: 
2019-10-12 22:31:22,994 494    [           main] DEBUG m.itheima.dao.IUserDao.findAll  - <==      Total: 6
User{id=41, username='老王', birthday=Tue Feb 27 17:47:08 CST 2018, sex='男', address='北京'}
User{id=42, username='小二王', birthday=Fri Mar 02 15:09:37 CST 2018, sex='女', address='北京金燕龙'}
User{id=43, username='小二王', birthday=Sun Mar 04 11:34:34 CST 2018, sex='女', address='北京金燕龙'}
User{id=45, username='传智播客', birthday=Sun Mar 04 12:04:06 CST 2018, sex='男', address='北京金燕龙'}
User{id=46, username='老王', birthday=Wed Mar 07 17:37:26 CST 2018, sex='男', address='北京'}
User{id=48, username='小马宝莉', birthday=Thu Mar 08 11:44:00 CST 2018, sex='女', address='北京修正'}
2019-10-12 22:31:22,997 497    [           main] DEBUG ansaction.jdbc.JdbcTransaction  - Resetting autocommit to true on JDBC Connection [com.mysql.jdbc.JDBC4Connection@148080bb]
2019-10-12 22:31:22,998 498    [           main] DEBUG ansaction.jdbc.JdbcTransaction  - Closing JDBC Connection [com.mysql.jdbc.JDBC4Connection@148080bb]
2019-10-12 22:31:22,998 498    [           main] DEBUG source.pooled.PooledDataSource  - Returned connection 343965883 to pool.

Process finished with exit code 0

注意

该工程为Idea创建的Maven工程，目录结构与创建的纯Java工程不同，单元测试也不同，若为纯Java工程，请自行改造！

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.itheima</groupId>
    <artifactId>itheima_mybatis_day01_01</artifactId>
    <version>1.0-SNAPSHOT</version>
    <!-- 打包方式-->
    <packaging>jar</packaging>
    <dependencies>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.4.5</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.6</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.11</version>
        </dependency>
    </dependencies>


</project>