### Question:
Preconditions { public static void checkNotEmpty(Object object, @Nullable ErrorCode message) { if (object == null) { throw new NulsRuntimeException(message); } if (object instanceof String && ((String) object).trim().length() == 0) { throw new NulsRuntimeException(message); } }  static void checkArgument(boolean expression, @Nullable ErrorCode message); static void checkNotNull(Object object, @Nullable ErrorCode message); static void checkNotEmpty(Object object, @Nullable ErrorCode message); static void checkNotNull(Object[] objects, @Nullable ErrorCode message);  }### Answer:
@Test public void checkNotEmpty() { }