I am developing a small game in Java and I am shipping it as a single Jar file. I want to store the high scores/best times for that game somewhere. Instead of storing it in a separate file, I would like to store it in the application itself (inside the Jar) so that its not lost. Is this possible at all ? If so, how to do it programatically.
Java does not give you tools to modify the JARs which are currently run. If you really want to do it, you have to guess the location of the JAR by yourself (which might reside on a read-only filesystem) and modify it the same way you would modify any archive file.
Bottom line: it’s a very bad idea, don’t do it! See this question for a much more reasonable solution.