Where is this java class from?
Recently James blogged about a nice addition to log4j. The submission even got applied already.
It uses the same “trick” that I had stashed away in my “toblog” folder and almost had forgotten about. Finding out the what jar file a class comes from can be quite useful at times. The straight forward approach is to lookup the resource and go from there.
Class type = yourinstance.getClass();
File jar = new File(type.getClassLoader().getResource(
type.getName().replace('.', '/') + ".class")
.toExternalForm()
.replaceFirst("^[^/]*", "")
.replaceFirst("!.*", ""));
But a much simpler and faster approach is to use the ProtectionDomain (if available).
Class type = yourinstance.getClass(); File jar = new File(type.getProtectionDomain() .getCodeSource().getLocation() .toURI());
Really quite simple but useful.