How to establish a connection between Java and a database

To establish a connection with a database, you can use Java’s JDBC (Java Database Connectivity) technology. Below is a simple example code that demonstrates how to use Java’s JDBC to connect with a database.

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class DatabaseConnection {
    public static void main(String[] args) {
        String url = "jdbc:mysql://localhost:3306/mydatabase"; // 数据库连接URL
        String username = "username"; // 数据库用户名
        String password = "password"; // 数据库密码
        try {
            // 加载数据库驱动
            Class.forName("com.mysql.cj.jdbc.Driver");
            // 建立数据库连接
            Connection conn = DriverManager.getConnection(url, username, password);
            // 连接成功，可以进行数据库操作
            // 关闭连接
            conn.close();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

In the example code above, it is necessary to first load the database driver and then establish a database connection using the `DriverManager.getConnection()` method. The `url` parameter represents the database connection URL, while `username` and `password` are the database’s login credentials. Please modify the database connection parameters in the example code according to your specific situation.