The Java compiler (javac) compiles applications with all necessary debug information by default. However, if the
-g:none compiler setting is used, no debug information is generated. In this case, you need to remove this setting from the compiler’s command line and use one of the following settings instead:
-gsetting - Generate debug information for source files and line numbers.
-g- Generate all debug information (for source files, line numbers and local variables).
When your application is ready for release, remember to recompile it with the settings you use for release builds.