Connection manager as a singleton

In PHP, the connection manager as a singleton is a common design pattern. As PHP editor Yuzu, we have conducted an in-depth study of the principles and applications of this design pattern. The main function of the connection manager is to centrally manage database connections, ensure that there is only one database connection instance in the application, avoid the overhead of repeatedly creating connections, and effectively control the life cycle of the connection. This design pattern has great practicality in development and can improve the performance and maintainability of the program. In this article, we will introduce in detail how the connection manager is implemented as a singleton and its application scenarios in actual projects.

Question content

Suppose I create an object to manage connections as a signleton, for example:

public class DatabaseConnection {

private static Connection con = null;

static

{ 

String url = "jdbc:`\[`mysql:/`\](mysql://)`/localhost:3306/org";`

String user = "root";
String pass = "root";

try {

Class.forName("com.mysql.jdbc.Driver");

con = DriverManager.getConnection(url, user, pass);

}

catch (ClassNotFoundException | SQLException e) {

e.printStackTrace();

}

}

public static Connection getConnection()

{

return con;
}

}

Do I understand correctly, with this approach I only create one connection instance and use it throughout the application. I just need to close the connection before exiting the application? I'm asking this question because I was told in the tutorial that the best option is to use try-with-resources to create the connection. But using try-with-resources or DatabaseConnection.getConnection().close I will close the connection and be unable to restore it later in the singleton application. Can you explain it to me?

Browsed stack Overflow and google but didn't find the answer

Workaround

You are making the connection inside a static block, and the static block is loaded during class loading. Therefore, to close the connection you must close the application.

If you want to create a singleton, then create a class and make the constructor private and inside that constructor define your database connection.

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