Question

I want your suggestion on the following pseudo-code. Please suggest how could I improve it, whether or not I could use some design patterns.

 // i'm receiving a string containing : id operation arguments data    = read(socket); tokens  = tokenize(data,' '); // tokenize the string based on spaces if(tokens[0] == 'A') {    if(tokens[1] == 'some_operation') {       // here goes code for some_operation , will use the remaining tokens as arguments for function calls    }    else if(tokens[1] == 'some_other_operation') {      // here goes code for some_other_operation , will use the remaining tokens    }    ...    else {      // unknown operation    } } else if(tokens[0] == 'B') {    if(tokens[1] == 'some_operation_for_B') {      // do some operation for B    }    else if(tokens[1] == 'yet_another_operation') {      // do yet_another_operation for B    }    ...    else {      // unknown operation    }  } 

I hope you get the point . The thing is I have a large number of id’s and each has it’s own operations , and I think it’s kinda ugly to have 10 screens of code containing a lot of if’s and else if’s.

Answer 1

Have a class for each ID which implements a common interface. Basically the Strategy pattern IIRC.

So you’d call (pseudo)code like:

StrategyFactory.GetStrategy(tokens[0]).parse(tokens[1..n])