fun reference(stateLabel: String): Unit
Looks up the output label and adds the found state as an reference input state.
stateLabel - The label of the output state specified when calling TransactionDSLInterpreter.output and friends.
fun reference(contractClassName: ContractClassName, state: ContractState): Unit
Creates an LedgerDSLInterpreter._unverifiedTransaction with a single reference input state and adds its reference as in input to the current transaction.