How do I....

[talliah]

I use showInputDialog OptioPane.

I want the user to enter a number.....How do I check the value of what the user enterd......If the user enterd a letter....or a word ....How do I check his input?

[xylex_blaiste]

use a try-catch block using a numberformatexception. i am not sure with this exception's name but look it up. this should do. so anytime the user enters a non-number character, the error is caught and the user will have to do it again.

[GunNam]

use try-catch blocks, or you can use "ifs" since they are more efficient.

for example, if you DO NOT have to worry about handling the input which allows a string or numeric:

if(input>=0)
{ do this }
else
{System.out.println("please enter a number");}