Pass Method Reference Using Supplier in Java

Question

Is there a way I can use the same method reference in these two lines for the getter? I tried a Supplier which works with the first statement but the second statement requires a Function.

Integer id = Integer.parseInt(accountModel.getExternalId());

accountsWithNonNumericIds.sort(Comparator.comparing(AccountModel::getExternalId));

Answer 1

The method reference can produce a Function , but not a Supplier , because in order to get the ID, you need to know the account to get it from.

Function<AccountModel,String> func = AccountModel::getExternalId;

Integer id = Integer.parseInt(func.apply(accountModel));

accountsWithNonNumericIds.sort(Comparator.comparing(func));