Java APIs

I am working on a website system that has a ton of class files. The original developer is gone, and I am soewhat familiar with java, but have never actually created class files. ( I have a wide programming background in CF, PHP, Perl, VB, Javascript, HTML, DHTML, ETC)

Anyway, I have the original *,java files, but when I run the jacac from the windows cmd promt, I get a million erros and the thing wont compile.

I cd intot he /j2sdk/bin directory, hten i type

javac d:/tomcat/blah/myfile.java

and it just returns like a hundred errors, i think its looking for some files to include, but im kinda lost... my JSP book is not helping, any ideas on where I can get help?

I havent changed the source files yet, just trying to compile them, so they shouldnt have any syntex errors, as the compiled file are already active on the server