Mybatis工程搭建

mybatis工程搭建

准备数据源

/*删除mybatis_demo数据库

drop database if exists mybatis_demo;

 

/*创建mybatis_demo数据库

create database mybatis_demo;

 

/*使用mybatis_demo数据库

use mybatis_demo;

 

/*创建account表

create table user (

    id int auto_increment primary key,

    username varchar(20),

    age int,

    score int

);

 

/*新增数据

insert into user (id, username, age, score) values

(1,'peter', 18, 100), (2,'pedro', 24, 200),

(3,'jerry', 28, 500), (4,'mike', 12, 300),

(5,'tom', 27, 1000);

  引入MySQL驱动包

<dependencies>

    <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->

    <dependency>

        <groupId>mysql</groupId>

        <artifactId>mysql-connector-java</artifactId>

        <version>8.0.23</version>

    </dependency>

</dependencies>

 

=====================

public class JDBCDemo {

    public static void main(String[] args) throws Exception {

        //1.注册驱动

        Class.forName("com.mysql.cj.jdbc.Driver");

        //2.获取连接

        Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/mybatis_demo", "root", "root");

        //3.获取Statement对象

        PreparedStatement preparedStatement = connection.prepareStatement("select * from user WHERE id = ?");

        preparedStatement.setInt(1, 1);

        //4.执行SQL语句返回结果集

        ResultSet resultSet = preparedStatement.executeQuery();

        //5.遍历结果集

        while (resultSet.next()) {

            System.out.println("username: " + resultSet.getString("username"));

            System.out.println("age: " + resultSet.getString("age"));

        }

        //6.释放资源

        resultSet.close();

        preparedStatement.close();

        connection.close();

    }

}

 

 

 

=======================

引入MyBatis依赖

<!-- https://mvnrepository.com/artifact/org.mybatis/mybatis -->

<dependency>

    <groupId>org.mybatis</groupId>

    <artifactId>mybatis</artifactId>

    <version>3.5.6</version>

</dependency>

<!-- https://mvnrepository.com/artifact/ch.qos.logback/logback-classic -->

<dependency>

    <groupId>ch.qos.logback</groupId>

    <artifactId>logback-classic</artifactId>

    <version>1.3.0-alpha5</version>

    <scope>test</scope>

</dependency>

=========================

新建编程式配置文件：StartNoXml.java

@SuppressWarnings({"SqlResolve", "SqlNoDataSourceInspection", "Duplicates"})

public class StartNoXml {

    public static void main(String[] args) throws SQLException {

        // 准备jdbc事务类

        JdbcTransactionFactory jdbcTransactionFactory = new JdbcTransactionFactory();

        // 配置数据源

        PooledDataSource dataSource = new PooledDataSource(

                "com.mysql.cj.jdbc.Driver",

                "jdbc:mysql://localhost:3306/mybatis_demo?useSSL=false",

                "root",

                "root");

        // 配置环境，向环境中指定环境id、事务和数据源

        Environment environment = new Environment.Builder("development")

                .transactionFactory(jdbcTransactionFactory)

                .dataSource(dataSource).build();

        // 新建 MyBatis 配置类

        Configuration configuration = new Configuration(environment);

        // 得到 SqlSessionFactory 核心类

        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(configuration);

        // 开始一个 sql 会话

        SqlSession session = sqlSessionFactory.openSession();

        // 得到 sql 连接并运行 sql 语句

        PreparedStatement preStatement = session

                .getConnection()

                .prepareStatement("SELECT * FROM user WHERE id = ?");

        preStatement.setInt(1, 1);

        ResultSet result = preStatement.executeQuery();

        // 验证结果

        while (result.next()) {

            System.out.println("username: " + result.getString("username"));

            System.out.println("age: " + result.getString("age"));

        }

        // 关闭会话

        session.close();

    }

}

 

=================================

配置文件配置MyBatis

<?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>

    <!-- 环境变量 -->

    <environments default="development">

        <environment id="development">

            <!-- 事务管理器 -->

            <transactionManager type="JDBC"/>

            <!-- 数据源 -->

            <dataSource type="POOLED">

                <property name="driver" value="com.mysql.cj.jdbc.Driver"/>

                <property

name="url" value="jdbc:mysql://localhost:3306/mybatis_demo?useSSL=false"/>

                <property name="username" value="root"/>

                <property name="password" value="root"/>

            </dataSource>

        </environment>

    </environments>

</configuration>