I have a problem extracting my current project into an executable jar file. When I\'m in eclipse and press the run button everything works fine, but when I do
When your app is packages as a JAR, there are no files other than the JAR itself. The File class is only for accessing resources on the local file system, but, as Jon Skeet said, you need to read from the application's classpath when it's been packaged into a JAR. See https://stackoverflow.com/a/3376393/639520