RedeemHouseToken

RedeemHouseToken.java

/**
*  Redeem tokens by calling RedeemNonFungibleTokens Flow.
*/
@StartableByRPC
    public static class RedeemHouseToken extends FlowLogic<SignedTransaction> {

        private final String evolvableTokenId;
        private final Party issuer;

        public RedeemHouseToken(String evolvableTokenId, Party issuer) {
            this.evolvableTokenId = evolvableTokenId;
            this.issuer = issuer;
        }

        @Override
        @Suspendable
        public SignedTransaction call() throws FlowException {
            // uuid column in vault_linear_states contains the uuid of the created asset on ledger
            UUID uuid = UUID.fromString(evolvableTokenId);
            // construct queryCriteria to get the created asset on ledger by using LinearStateCriteria
            // get all the unconsumed states from vault_linear_states having uuid
            QueryCriteria queryCriteria = new QueryCriteria.LinearStateQueryCriteria(null, ImmutableList.of(uuid), null,
                    Vault.StateStatus.UNCONSUMED, null);
            // use vaultservice to hit the vault using the query criteria
            StateAndRef<RealEstateEvolvableTokenType> stateAndRef = getServiceHub().getVaultService().
                    queryBy(RealEstateEvolvableTokenType.class, queryCriteria).getStates().get(0);
           // get the state from StateAndRef returned by the query
            RealEstateEvolvableTokenType evolvableTokenType = stateAndRef.getState().getData();
            LinearPointer linearPointer = new LinearPointer(evolvableTokenType.getLinearId(), RealEstateEvolvableTokenType.class);
            // token pointer is a linear pointer to created real estate asset
            TokenPointer token = new TokenPointer(linearPointer, evolvableTokenType.getFractionDigits());
            // redeem token by specifying the issuer
            return (SignedTransaction) subFlow(new RedeemNonFungibleTokens(token, issuer));
        }
    }