I do not have JPA install setup, but I believe reading the QueryDslJpaRepository documentation, you can simply do this:
OrderSpecifier<String> sortOrder1 = QDealer.dealer.dealerType.asc();
OrderSpecifier<String> sortOrder2 = QDealer.dealer.dealerCode.desc();
Iterable<Dealer> results = dlrRpstry.findAll(where, sortOrder1, sortOrder2);
Let us know if it works. Here is a link to a stackoverflow question/answer that explains the ... parameter syntax on the findAll() method:
https://stackoverflow.com/a/12994104/2879838
This means you can have as many OrderSpecifiers as you want as optional parameters to the function.