### Question:
CommonHelper { public static @NotNull String formatThrowable(@NotNull Throwable throwable) { StackTraceElement[] trace = throwable.getStackTrace(); return throwable.getClass().getSimpleName() + " : " + throwable.getMessage() + ((trace.length > 0) ? " @ " + throwable.getStackTrace()[0].getClassName() + ":" + throwable.getStackTrace()[0].getLineNumber() : ""); } private  CommonHelper(); static MemoryMXBean memoryMXBean(); static ClassLoadingMXBean classLoadingMXBean(); static OperatingSystemMXBean operatingSystemMXBean(); static RuntimeMXBean runtimeMXBean(); static ThreadMXBean threadMXBean(); static long memoryPoolMXBeanCollectionUsage(); static Integer fromString(String s); static Boolean booleanFromString(String s); static Long longFromString(String s); static UUID tryParse(String s); static int longToInt(long in); static int calculateMaxMemory(); static int getTotalSystemMemory(); static String getIpAddress(@NotNull String input); static @Unmodifiable @NotNull Collection<String> getAllAvailableIpAddresses(); static void setSystemPropertyIfUnset(@NotNull String property, @NotNull String value); static @NotNull String formatThrowable(@NotNull Throwable throwable); static ReferencedOptional<T> findEnumField(Class<T> enumClass, String field); static final ExecutorService EXECUTOR; static final ScheduledExecutorService SCHEDULED_EXECUTOR_SERVICE; static final ArrayDeque<String> EMPTY_STRING_QUEUE; static final DateFormat DATE_FORMAT; static final DecimalFormat DECIMAL_FORMAT; }### Answer:
@Test void testFormatThrowable() { String expected = "NullPointerException : null @ systems.reformcloud.reformcloud2.executor.api.CommonHelperTest:74"; Assertions.assertEquals(expected, CommonHelper.formatThrowable(new NullPointerException())); }