JSF 2.0 How a CAPTCHA works

Can sombody recommend me a good captcha tool for my JSF pages? Is there any captcha tool included in JEE6 or i have to add it to my project, like an external .jar?

Also is there any br开发者_运维知识库ief tutorial on how to include it in my program? or Does Someone what would be the steps i should follow to do so?(I never used a captcha before).

Jcapthca is good. You can use it at different levels (just for image generation or us their servlet), it would be easy to use in the t-edd's example if you need more advanced captcha images.

If you're using PrimeFaces, you could use the <p:captcha> component.

Here is good example I thing you can use. There is no integrated support in JEE6, you have to do this yourself as in provided example or you have to get some componenet that has this functionality. I know of another one in primefaces components here (it uses popular reCAPTCHA componenet)

If you're using myfaces, you can use the <t:captcha> component. It works without the internet too.