transactionBuilder.java

var txBuilder = ledgerService.createTransactionBuilder() //build sample transaction to test
                .setNotary(notary.getName())
                .setTimeWindowBetween(Instant.now(), Instant.now().plusMillis(Duration.ofDays(1).toMillis()))
                .addOutputState(iouState)
                .addInputState(inputStateRef)
                .addCommand(new IOUContract.Issue())
                .addCommand(new IOUContract.Transfer())
                .addSignatories(iouState.getParticipants());