I created my own SecurityException class because I felt that the java.lang.SecurityException didn't really suit the needs of this application. Normally the java.lang.SE is used with a security manager (which I didn't use), and it is also a runtime exception. I wanted to force my exception to be caught, so creating my own seemed to be a better design decision to me.
“Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning.” - Rich Cook