您可以像这样使用设计模式Singleton Connection：

You can use the design pattern Singleton Connection like this :

1-创建一个类SingletonConnection.java，如下所示：

1- create a class SingletonConnection.java look like that :

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

public class SingletonConnection   {


    private static Connection connection = null ;
    static 
    {
        try{
            Class.forName("com.mysql.jdbc.Driver");
            connection = DriverManager.getConnection
                    ("jdbc:mysql://localhost:3306/gestion_comptes","root","");
        }catch(Exception ex)
        {

        }

    }
    public static Connection getConnection() throws Exception {
        return connection;
    }


}

并在你的其他类称之为：

And in your other class call it like that :

 public  class DaoImpl{

        public Connection connection = SingletonConnection.getConnection();

        public DaoImpl() throws Exception 
        {
            if(connection==null)
                throw new Exception("impossible de se connecter à la base de données");
        }
}