JulZlgBridge { public static boolean isInstalled() { return Arrays.stream(getRootLogger().getHandlers()).filter(ZlgHandler.class::isInstance).findFirst().isPresent(); } private  JulZlgBridge(); static boolean isInstalled(); static void install(Zlg zlg); static void installAllHandlers(Set<Handler> handlers); static void uninstall(); static Set<Handler> uninstallAllHandlers(); static void stashAllHandlers(); static void unstashAllHandlers(); static Logger getRootLogger();  }
@Test public void testIsInstalled() { assertFalse(JulZlgBridge.isInstalled()); JulZlgBridge.install(Zlg.nop()); assertTrue(JulZlgBridge.isInstalled()); JulZlgBridge.uninstall(); assertFalse(JulZlgBridge.isInstalled()); }