Running launcher.java gives me this error:
Exception in thread "main" java.lang.NullPointerException: Cannot invoke "java.net.URL.toExternalForm()" because "location" is null
at java.desktop/javax.swing.ImageIcon.<init>(ImageIcon.java:232)
at main.launcher$1.<init>(launcher.java:24)
at main.launcher.main(launcher.java:22)