Mybatis学习1【环境搭建】

1.IDEA连接MySQL





2.新建表并插入数据


3.Maven导入jar包
Maven配置：https://www.cnblogs.com/stars-one/p/10958796.html

<?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>org.example</groupId>
    <artifactId>day01_st_01mybatis</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>jar</packaging>

    <dependencies>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.4</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.48</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.12</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.2</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

</project>

生成getter&setter和toString快捷键

User

package org.example.domain;

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

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 + '\'' +
                '}';
    }
}

5.创建接口


IUserDao

package org.example.domain.Dao;

import org.example.domain.User;

import java.util.List;

/*
用户的持久层接口
 */
public interface IUserDao {
     
    /*
    查询所有操作
     */
    List<User> findAll();
}

6.Mybatis环境


Mybatis约束：
①主配置文件

②指定映射配置文件




IUserDao.xml

<?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="org.example.Dao.IUserDao">
    <!-- 配置查询所有 -->
    <select id="findAll">
        select * from user
    </select>
</mapper>

sqlMapConfig.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">
<!-- mybatis主配置文件 -->
<configuration>
    <!-- 配置环境 -->
    <environments default="mysql">
        <!-- 配置mysql环境 -->
        <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">
                <!-- 配置连接数据库的4个基本信息 -->
                <property name="drive" value="com.mysql.jc.jbdc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306"/>
                <property name="username" value="root"/>
                <property name="password" value="0729"/>
            </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="org/example/Dao/IUserDao.xml"/>
    </mappers>
</configuration>