public static void assertAccountsInAccountService(Collection<Account> accounts, int expectedAccountCount,
      AccountService accountService) {
    assertEquals("Wrong number of accounts in accountService", expectedAccountCount,
        accountService.getAllAccounts().size());
    for (Account account : accounts) {
      assertAccountInAccountService(account, accountService);
    }
  }
Assert a collection of {@link Account}s exist in the {@link AccountService}.
@param accounts The collection of {@link Account}s to assert their existence.
@param expectedAccountCount The expected number of {@link Account}s in the {@link AccountService}.
@param accountService The {@link AccountService} to assert {@link Account}s existence.
ambry-test-utils/src/main/java/com/github/ambry/utils/AccountTestUtils.java