I have the following structure:
myapp.jar
lib/
myapp.jar is an executable jar that includes a splash screen image resource and uses the SplashScreen-Image manifest entry. lib/ contains a bunch of other jar files.
If I run java -jar myapp.jar, the splash screen is displayed but (as expected) the program can't find its dependencies in lib/.
If I run java -cp myapp.jar:lib/* mypackage.MainClass, it finds its dependencies but the splash screen is not shown. SplashScreen.getSplashScreen() returns null.
If I run java -cp myapp.jar:lib/* -splash:images/splash.jpg mypackage.MainClass, the splash screen still doesn't work. Apparently it's treating images/splash.jpg as a relative filesystem path, not a classpath resource.
Trying to combine -cp with -jar, i.e., java -cp myapp.jar:lib/* -jar myapp.jar behaves exactly like java -jar myapp.jar. -cp is apparently ignored with -jar.
Is there any solution besides supplying the splash image separately from the executable jar?
You can add a Class-Path entry to your jar manifest, so you can use the -jar option while still finding your dependencies.