【Java基础】Gradle配置连接Mysql数据库

目录

Gradle下载依赖

代码示例

---

Gradle下载依赖

// https://mvnrepository.com/artifact/mysql/mysql-connector-java
//各位同学根据自己的mysql版本访问上面的链接下载自己的依赖
implementation 'mysql:mysql-connector-java:8.0.29'

代码示例

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.sql.*;

public class DBConnection {
    private static final Logger log = LoggerFactory.getLogger(DBConnection.class);
    private static final String JDBC_DRIVER = "com.mysql.cj.jdbc.Driver";
    private static final String DB_URL = "jdbc:mysql://localhost:3306/automaiton?useSSL=false&allowPublicKeyRetrieval=true&serverTimezone=UTC";
    private static final String USER_NAME = "root";
    private static final String PASSWORD = "123456";
    private static Connection conn = null;

    public void connectToDB(String url, String username, String password) {
        try {
            log.info("Connect DB...");
            Class.forName(JDBC_DRIVER);
            conn = DriverManager.getConnection(DB_URL, USER_NAME, PASSWORD);
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    public String getUserName(){
        String query = "select * from user";
        String username = null;
        try {
            Statement stmt = conn.createStatement();
            ResultSet rs = stmt.executeQuery(query);
            while (rs.next()) {
                username = rs.getString(1);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return username;
    }

    public void closeDBConnection() {
        try{
            if(conn != null) {
                conn.close();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    public static void main(String[] args) {
        DBConnection dbConnection = new DBConnection();
        dbConnection.connectToDB(DB_URL, USER_NAME, PASSWORD);
        System.out.println(dbConnection.getUserName());
        dbConnection.closeDBConnection();
    }
}