How to pass final call object in method param in java

Question

This is my final call

public final class TransferRequest implements Serializable {
    private static final long serialVersionUID = 1L;

    /**
     * Returns a new builder for creating a transfer request.
     *
     * @return the first build step
     */
    public static ReferenceStep builder() {
        return new Builder();
    }

    public interface ReferenceStep {
        /**
         * @param transactionRef client defined transaction reference
         * @return the next build step
         */
        TypeStep reference(String transactionRef);
    }

    public interface TypeStep {
        /**
         * @param transactionType the transaction type for grouping transactions or other purposes
         * @return the next build step
         */
        AccountStep type(String transactionType);
    }

    public interface AccountStep {
        /**
         * @param accountRef the client defined account reference
         * @return the next build step
         */
        AmountStep account(String accountRef);
    }

    public interface AmountStep {
        /**
         * @param money the transfer amount for the account
         * @return the final build step
         */
        BuildStep amount(Money money);
    }

    public interface BuildStep {
        AmountStep account(String accountRef);

        TransferRequest build();
    }

    private static final class Builder implements ReferenceStep, TypeStep, AccountStep, AmountStep, BuildStep {
        private final TransferRequest request = new TransferRequest();

        private String accountRef;

        @Override
        public TypeStep reference(String transactionRef) {
            request.transactionRef = transactionRef;
            return this;
        }

        @Override
        public AccountStep type(String transactionType) {
            request.transactionType = transactionType;
            return this;
        }

        @Override
        public AmountStep account(String accountRef) {
            this.accountRef = accountRef;
            return this;
        }

        @Override
        public BuildStep amount(Money money) {
            request.legs.add(new TransactionLeg(accountRef, money));
            accountRef = null;
            return this;
        }

        @Override
        public TransferRequest build() {
            if (request.legs.size() < 2) {
                throw new IllegalStateException("Expected at least 2 legs");
            }
            return request;
        }
    }

    private String transactionRef;

    private String transactionType;

    private final List<TransactionLeg> legs = new ArrayList<TransactionLeg>();

    private TransferRequest() {
    }

    public List<TransactionLeg> getLegs() {
        return Collections.unmodifiableList(legs);
    }

    public String getTransactionRef() {
        return transactionRef;
    }

    public String getTransactionType() {
        return transactionType;
    }
}

This is my interface which contains two methods

public interface TransferService {

    void transferFunds(TransferRequest transferRequest)
            throws InsufficientFundsException, AccountNotFoundException;

    List<Transaction> findTransactions(String accountRef)
            throws AccountNotFoundException;
}

In Implementation class how can i get "getLegs(),"getTransactionRef()" & getTransactionType()" data?

public void transferFunds(TransferRequest transferRequest)
            throws InsufficientFundsException, AccountNotFoundException {


        // Validating the legs amounts
        List<TransactionLeg> legs = transferRequest.getLegs();              


        TransactionDO transaction = new TransactionDO(transferRequest.getTransactionRef(),transferRequest.getTransactionType(), new Date());


        for (TransactionLeg leg : legs) {
            AccountDO account = accountRepository.findByAccountRef(leg.getAccountRef());
            if (account == null) {
                throw new AccountNotFoundException("the account '"
                        + leg.getAccountRef() + "' does not exist");
            }

            if(!account.isActive())
            {
                throw new AccountNotFoundException("the account '"
                        + leg.getAccountRef() + "' is closed");
            }

            TransactionEntryDO entry = new TransactionEntryDO(transaction,
                    account.getAccountRef(), leg.getAmount().getAmount(), leg
                            .getAmount().getCurrency().toString());

            Money balanceToBe;
            try {
              String accountCurrencyCode = account.getCurrency();
                balanceToBe = MoneyUtils.add(
                        MoneyUtils.toMoney(account.getBalance().toString(),
                            accountCurrencyCode), MoneyUtils.toMoney(leg.getAmount().getAmount().toString(), accountCurrencyCode));

            } catch (Exception e) {
                throw new IllegalArgumentException(e.getMessage());
            }


            account.setBalance(balanceToBe.getAmount());
            accountRepository.save(account);
            transaction.getTransactionEntries().add(entry);
        }

        transactionRepository.save(transaction);

    }

how can call service impl class from test method....

Answer 1

Somewhat I am puzzled. You posted the complete code of the TransferRequest class, but yet you do not know how to instantiate it? I assume that you do not know the builder pattern. Your class is instantiated with a builder:

TransferRequest tr = TransferRequest.builder()
        .reference(...)
        .type(...)
        .account(...)
        .amount(...)
        .build();

Note, that the several interfaces serve the following purpose: You can only call the method reference(...) on the returned object from method builder(). Then you can only call the method type(...), and so on. These builder steps force you to use the building methods in the correct order. Note also, that you can repeat the calls to account(...) and amount(...).