public static RemoteCall<TransactionReceipt> sendFunds(
            Web3j web3j,
            Credentials credentials,
            String toAddress,
            BigDecimal value,
            Convert.Unit unit)
            throws InterruptedException, IOException, TransactionException {

        TransactionManager transactionManager = new RawTransactionManager(web3j, credentials);

        return new RemoteCall<>(
                () -> new Transfer(web3j, transactionManager).send(toAddress, value, unit));
    }
@Test
    public void testTransferInvalidValue() {

        assertThrows(
                UnsupportedOperationException.class,
                () ->
                        sendFunds(
                                SampleKeys.CREDENTIALS,
                                ADDRESS,
                                new BigDecimal(0.1),
                                Convert.Unit.WEI));
    }