TOMCAT ENCRYPTION OF CREDIT CARD NUMS???????

Hi all, Help badly needed by anyone with ANY information on the foollowing: I am designing an online booking system using JSP, Java Beans and Tomcat for a project at uni. Does anyone have any information on how to encrypt a credit card number with Tomcat in mind. Surely there is some code I code

IM LOST, ERROR 500????

Hi Im writing my first little program that will welcome a user once she enters and submits her details into a web page.There is no problem Writing the JSP files but I cannot start a new .java file in Jbuilder, so I write it in Homesite, save it as .java and attempt to compile it to .class in Jbuild