Two ways: 1. If you don't have an IDE, add some <%System.out.println();%>. 2. If you have an IDE. In Tomcat, the system compiles jsp into $tomcat_home$/work/your_project directory. Including this directory into your IDE source directory. Then, you can set breakpoint in your IDE.
1. Design your system to use helper classes such as JavaBeans that you can test separately from the JSP environment. Write a utility to test that bean with a variety of conditions. 2. Download my chapter on debugging servlets and JSP from web page for my Servlets and JSP book Bill [ December 14, 2002: Message edited by: William Brogden ]
The following plugin for eclipse allows you to step through the generated java code for a jsp, use breakpoints etc: http://www.sysdeo.com/eclipse/tomcatPlugin.html This type of thing is not usually required as print statements normally suffice. The other advice about separating the logic from the display elements is key. Anthony Nolan Big Picture Solutions