Hey all, I use Windows XP and atm, I need to increase the memory allocated from default 64M(i think?) to 500M.

So I'm in the directory where the jar file is (I'm using JFLAP if anybody is familiar with it, it's for statemachines/automata) and i type the following: java -Xmx500m -classpath JFLAP.jar JFLAP. However I get an error saying that 'java' is not recognized as an internal or external command, operable program or batch file.

Any question as to how I can go about this? Any help would be deeply appreciated.

Add the java bin directory to your system path (not classpath) environment variable, or use the full path to java when executing it.