pls I need ur assistance

Am writing a java program,how do I include validation check on all input?My program is designed to manipulate input in double and integer only.The validation check has to return an error if the user inputs nothing(i.e. blank space) or inputs a string character e.g(a,b h...),who can help me with the code I need to do this validation check?

Thanks in Advance!!!

[374 byte] By [latimoorea] at [2007-10-2 14:55:26]