jdbc连接mysql数据库

导入mysql-connector-java-6.0.6.jar

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

public class DBHelper {
	private static final String driver = "com.mysql.cj.jdbc.Driver";	//数据库驱动，maven下载的jar包需要加cj
	//连接数据库的URL地址
	//serverTimezone=GMT%2B8 处理异常
	private static final String url = "jdbc:mysql://localhost:3306/shopping?useUnicode=true&characterEncoding=UTF-8&serverTimezone=GMT%2B8&useSSL=false";
	private static final String username = "root";	//数据库的用户名
	private static final String password = "root";	//数据库的密码
	
	private static Connection conn = null;
	
	//静态代码块负责加载驱动
	static
	{
		try
		{
			Class.forName(driver);
		}
		catch(Exception ex)
		{
			ex.printStackTrace();
		}
	}
	
	//单例模式返回数据库连接对象
	public static Connection getConnection() throws Exception
	{
		if(conn == null)
		{
			conn = DriverManager.getConnection(url, username, password);
			return conn;
		}
		return conn;
	}
	
	//测试是否正常连接
	public static void main(String[] args) {
		try {
			Connection conn = DBHelper.getConnection();
			if(conn != null)
			{
				System.out.println("数据库连接正常！");
			}
			else
			{
				System.out.println("数据库连接异常！");
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
}