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Constructing an object with three different member variables

Hi Experts,

I have to provide an API to users who need to send some command to the server.
the commands will be of the form
class API
{
void sendWrite()
void sendUpdate()
void sendRead()
void sendDelete()
};

I need to construct an object with the following which is the command to be send to a server. The command is of this form(i.e, three separate lines with the following format)
msg:::write
id:::123
data::dataValue

msg is one of write, read, delete, update, etc.
id is not relevant for now.
The dataValue may be a string, int or a json encoded string. I will be setting this data field according the command.

I have another class that actually send this string to the server.

bool cmdSender::sendCommand()
{

}

What I am trying to do is to create the commandMsgs and
do something like
sender->sendCommand(cmd.getString());

So, I need to create a Command class and constuct it as per the request. What is the better way to do it.

class Command
{

}

So, I need to create the Command objects by simply passing

Command *cmd = new Command(write, 123, dataValueString);
then call sendCommand(cmd->getString()) or something like this.

SOLUTION

dpearson

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tampnic

You might want to look into using a Factory design pattern. Each type of command has its own class, all derived from a base "Command" class - a "Command_factory" class is built which creates objects of the correct type and returns a "Command" pointer. Another design pattern of use could be the Command pattern.

I recently used the Factory and Command design patterns for a web-update application. I found them to be a little extra work than the simple design I originally envisaged, but the benefits were realised as I added new types of commands to my application without changing the application logic. The command logic was encapsulated in the new command classes I was creating.

Cheers,
Chris

SOLUTION

jkr

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ASKER CERTIFIED SOLUTION

evilrix

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