This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
Are you asking what the "current working directory" is for your web application? I think that when running in Tomcat, the current working directory for all web applications is tomcat_home/bin. Why? Because the current working directory is an operating system concept that relates to the process, which in this case is the JVM, and the JVM is started from tomcat_home/bin.