first, we need a pattern to descripbe this situation, then we implement the customer's specification,
if you have a server, you write a application which is responsible for answering your customer's request , you have 3 customers now, they have same interface but a little bit different implementation, when you design the software, you know you will have more customers in future, if you need modify a lot of code when you add a new client, sometimes you can't remember where you should add code for the new client, you find you should design your project well at the first
that's it.
if you have a server, you write a application which is responsible for answering your customer's request , you have 3 customers now, they have same interface but a little bit different implementation, when you design the software, you know you will have more customers in future, if you need modify a lot of code when you add a new client, sometimes you can't remember where you should add code for the new client, you find you should design your project well at the first
that's it.