MyBatis工程搭建

JDBC连接及操作数据库

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>

代码实现

public class JDBCDemo {
    public static void main(String[] args) throws Exception {
        Class.forName("com.mysql.cj.jdbc.Driver");
        Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/mybatis_demo", "root", "root");
        PreparedStatement preparedStatement = connection.prepareStatement("select * from user WHERE id = ?");
        preparedStatement.setInt(1, 1);
        ResultSet resultSet = preparedStatement.executeQuery();
        while (resultSet.next()) {
            System.out.println("username: " + resultSet.getString("username"));
            System.out.println("age: " + resultSet.getString("age"));
        }
        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>

代码实现

@SuppressWarnings({"SqlResolve", "SqlNoDataSourceInspection", "Duplicates"})
public class StartNoXml {
    public static void main(String[] args) throws SQLException {
        JdbcTransactionFactory jdbcTransactionFactory = new JdbcTransactionFactory();
        PooledDataSource dataSource = new PooledDataSource(
                "com.mysql.cj.jdbc.Driver",
                "jdbc:mysql://localhost:3306/mybatis_demo?useSSL=false",
                "root",
                "root");
        Environment environment = new Environment.Builder("development")
                .transactionFactory(jdbcTransactionFactory)
                .dataSource(dataSource).build();
        Configuration configuration = new Configuration(environment);
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(configuration);
        SqlSession session = sqlSessionFactory.openSession();
        PreparedStatement preStatement = session
                .getConnection()
                .prepareStatement("SELECT * FROM user WHERE id = ?");
        preStatement.setInt(1, 1);
        ResultSet result = preStatement.executeQuery();
        while (result.next()) {
            System.out.println("username: " + result.getString("username"));
            System.out.println("age: " + result.getString("age"));
        }
        session.close();
    }
}

编程式配置方法

@SuppressWarnings({"SqlResolve", "SqlNoDataSourceInspection", "Duplicates"})
public class StartNoXml {
public static void main(String[] args) throws SQLException {
JdbcTransactionFactory jdbcTransactionFactory = new JdbcTransactionFactory();
PooledDataSource dataSource = new PooledDataSource(
"com.mysql.cj.jdbc.Driver",
"jdbc:mysql://localhost:3306/mybatis_demo?useSSL=false",
"root",
"root");
Environment environment = new Environment.Builder("development")
.transactionFactory(jdbcTransactionFactory)
.dataSource(dataSource).build();
Configuration configuration = new Configuration(environment);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(configuration);
SqlSession session = sqlSessionFactory.openSession();
PreparedStatement preStatement = session
.getConnection()
.prepareStatement("SELECT * FROM user WHERE id = ?");
preStatement.setInt(1, 1);
ResultSet result = preStatement.executeQuery();
while (result.next()) {
System.out.println("username: " + result.getString("username"));
System.out.println("age: " + result.getString("age"));
}
session.close();
}
}

配置文件配置MyBatis

代码实现

<?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>