Change a single cell keeping the others unchanged

Hi everyone,
I'm new in Knime.

I know that with Rule Engine node you can change the values of the cells in a table.
But I need to change just a single cell keeping the others unchanged and I don't know how to do it with Rule Engine.
So I tried the Java Snipped (Simple) node, but I got the same problem of Rule Engine node: I have to specify the value for all the rows of a column, so I cannot change only one of them and keep the others unchanged.
Infact, in the code below, I tried to write only the IF branch, bu Java Snipped says that I must return always an integer value for all the branches, so I cannot do that.
Since I am changing a parametric column, I can access to my old value only using the returned value by the ELSE branch, but Java Snipped does not accept it.

if ($id$ == $${Iid}$$)
	return $${ICount*(id)}$$;
else
	return $$${Stype_success}$$$;

Please help me.
Thanks.

You must return the same data type in both branches of your if statement. You cannot return in integer and a string at the same time. Try "return Integer.toString($${ICount*(id)}$$);" for the true part and set the return type to string.