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Generating captcha (alpha numeric) in java

Vinod Vinu
Ranch Hand

Joined: Aug 30, 2009
Posts: 217
Hi, can someone give me any idea of generating randon alphanumeric words in java. I do not want alphanumeric inside an image like usually we see in various web sites.
I just need random alphanumeric series.


Vinod Kumar Nair
"Any fool can write code that a computer can understan. Good programmers write code that humans can understand."
fred rosenberger
lowercase baba

Joined: Oct 02, 2003
Posts: 11880

just generate a random number from 1-36, and map them to A-Z plus 0-9.

There are only two hard things in computer science: cache invalidation, naming things, and off-by-one errors
Campbell Ritchie

Joined: Oct 13, 2005
Posts: 44515
Adding random affine transforms, changes of font, etc, will help.
I agree. Here's the link:
subject: Generating captcha (alpha numeric) in java
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