@Nonnull
	public static List<String> getSystemPackages() {
		if (systemPackages == null) {
			synchronized (ClasspathUtil.class) {
				if (systemPackages == null) {
					systemPackages = ModuleFinder.ofSystem().findAll().stream()
							.flatMap(moduleReference -> moduleReference.descriptor().exports().stream())
							.map(ModuleDescriptor.Exports::source)
							.distinct()
							.collect(Collectors.toList());
				}
			}
		}
		return systemPackages;
	}
@return List of package names belonging to the core JDK.
recaf-core/src/main/java/software/coley/recaf/util/ClasspathUtil.java