如何在Java中建立一个客户机-服务器程序和一个数据库？

Question

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class test2 {

    public static void main(String[] args) {
        
        String url = "jdbc:mysql://localhost:3306/CovidPreventation";
        String username = "test";
        String password = "test";

        System.out.println("Connecting database...");

        try (Connection connection = DriverManager.getConnection(url, username, password)) {
            System.out.println("Database connected!");
        } catch (SQLException e) {
            throw new IllegalStateException("Cannot connect the database!", e);
        }
    
    }

}

Answer 1

您所需要的jdbc驱动程序，可以在以下站点获得：https://mvnrepository.com/artifact/mysql/mysql-connector-java

并将jar文件添加到ide中

在您需要在代码中调用它之后，如下所示：

public static Connection getConnection(String dbURL, String userName, 
            String password) {
        Connection conn = null;
        try {
            Class.forName("com.mysql.jdbc.Driver");
            conn = DriverManager.getConnection(dbURL, userName, password);
            System.out.println("connect successfully!");
        } catch (Exception ex) {
            System.out.println("connect failure!");
            ex.printStackTrace();
        }
        return conn;
    }