Question

I have a form made in JSP, here I have multiple buttons – “Approve, Reject, Save, Cancel”.
For every submit, the control goes to a single Controller(Servlet), and there I am handling this submit as ::

String methodName = (String) request.getParameter("methodName");
if(methodName.trim.toLower().equals("approve")) 
{
  approve_Claim(parameters);
}
else if(methodName.trim.toLower().equals("reject")) 
{
  reject_Claim(parameters);
}
else if(methodName.trim.toLower().equals("save")) 
{
  save_Claim(parameters);
}
else if(methodName.trim.toLower().equals("cancel")) 
{
  cancel_Claim(parameters);
}

Is there a way to remove these multiple if’s,
please suggest

Answer 1

It looks like you basically want a mapping from methodName.trim().toLower() to some sort of “claim action” which takes parameters. Create an interface like this:

interface ClaimAction
{
    void execute(Parameters parameters);
}

Then implement this with classes of CancelClaimAction, ApproveClaimAction etc. Next create a Map<String, ClaimAction> mapping “approve” to an ApproveClaimAction etc. Then:

String actionName = methodName.trim().toLower(Locale.US));
ClaimAction action = CLAIM_ACTION_MAPPING.get(actionName);
if (action != null)
{
    action.execute(parameters);
}
else
{
    // Error case, presumably.
}

You could use enums to do this, but I’d expect each of these classes to have enough work to do that it’s worth separating them out and testing each one individually.