How to use Observable.fromCallable() with a checked Exception?

Question

Observable.fromCallable() is great for converting a single function into an Observable. But how do you handle checked exceptions that might be thrown by the functio

Answer 1

You could also do this to return checked exceptions:

return Observable.fromCallable(() -> {
  sharedPreferences.edit()
          .putString(DB_COMPANY, LoganSquare.serialize(
                  CompanyDBTransformation.get(user.getCompany())
          ))
          .apply();
  return user;
  }).onErrorResumeNext(
            throwable -> Observable.error(new CompanySerializationException(throwable))
    );

So here I'm serializing taking the IOException risk, and I'm giving back a more descriptive description.