Spend from a multisig address

MultisigAddressExample.java

import com.bloxbean.cardano.client.account.Account;
import com.bloxbean.cardano.client.address.AddressProvider;
import com.bloxbean.cardano.client.api.model.Amount;
import com.bloxbean.cardano.client.backend.api.BackendService;
import com.bloxbean.cardano.client.backend.blockfrost.common.Constants;
import com.bloxbean.cardano.client.backend.blockfrost.service.BFBackendService;
import com.bloxbean.cardano.client.cip.cip20.MessageMetadata;
import com.bloxbean.cardano.client.common.model.Networks;
import com.bloxbean.cardano.client.crypto.VerificationKey;
import com.bloxbean.cardano.client.example.Constant;
import com.bloxbean.cardano.client.function.helper.SignerProviders;
import com.bloxbean.cardano.client.quicktx.QuickTxBuilder;
import com.bloxbean.cardano.client.quicktx.Tx;
import com.bloxbean.cardano.client.transaction.spec.script.NativeScript;
import com.bloxbean.cardano.client.transaction.spec.script.ScriptAll;
import com.bloxbean.cardano.client.transaction.spec.script.ScriptPubkey;
import org.junit.jupiter.api.Test;

public class MultisigAddressExample extends QuickTxBaseTest {
    private BackendService backendService = new BFBackendService(Constants.BLOCKFROST_PREPROD_URL, Constant.BF_PROJECT_KEY);

    String sender1Mnemonic = "<sender1 mnemonic>";
    Account sender1 = new Account(Networks.testnet(), sender1Mnemonic);
    String sender1Addr = sender1.baseAddress();

    String sender2Mnemonic = "<sender2 menmonic>";
    Account sender2 = new Account(Networks.testnet(), sender2Mnemonic);
    String sender2Addr = sender2.baseAddress();

    //Get a native script (type=all) from two accounts
    public NativeScript getMultisigScript(Account sender1, Account sender2) throws Exception {
        //sender1 - Account object1
        var pubKeyBytes1 = sender1.publicKeyBytes();
        var vkey1 = VerificationKey.create(pubKeyBytes1);

        //sender2 - Account object2
        var pubKeyBytes2 = sender2.publicKeyBytes();
        var vkey2 = VerificationKey.create(pubKeyBytes2);

        var scriptPubkey1 = ScriptPubkey.create(vkey1);
        var scriptPubkey2 = ScriptPubkey.create(vkey2);

        //Create ScriptAll native script
        var scriptAll = new ScriptAll();
        scriptAll.addScript(scriptPubkey1);
        scriptAll.addScript(scriptPubkey2);

        return scriptAll;
    }

    //Get a multi-sig address from a native script
    public String getMultisigAddress(NativeScript script) {
        var multiSigAddr = AddressProvider.getEntAddress(script, Networks.testnet()).toBech32();
        return multiSigAddr;
    }

    //https://preprod.cardanoscan.io/transaction/9bc0b73918052f7cabd49f4ceb7348bb9cef4f7170e50807b2af2f37c067f287
    //Pay to multi-sig address
    @Test
    public void payToMultiSigAddress() throws Exception {
        var multisigScript = getMultisigScript(sender1, sender2);
        var multiSigAddr = getMultisigAddress(multisigScript);

        //Pay to multi-sig address
        var payTx = new Tx()
                .payToAddress(multiSigAddr, Amount.ada(50))
                .attachMetadata(MessageMetadata.create().add("Transfer to multi-sig address"))
                .from(sender1Addr);

        var result = new QuickTxBuilder(backendService)
                .compose(payTx)
                .withSigner(SignerProviders.signerFrom(sender1))
                .completeAndWait(System.out::println);
    }

    //https://preprod.cardanoscan.io/transaction/92189ff220d576af8f68eea45d7543a8092cfa78c8224c5d3553ae07340e9ad6
    @Test
    public void spendFromMultisigAddress() throws Exception {
        var multisigScript = getMultisigScript(sender1, sender2);
        var multiSigAddr = getMultisigAddress(multisigScript);

        var spendTx = new Tx()
                .payToAddress(receiver1Addr, Amount.ada(2))
                .attachMetadata(MessageMetadata.create().add("Spend from multi-sig address - signed by both sender1 & sender2"))
                .from(multiSigAddr);

        var result = new QuickTxBuilder(backendService)
                .compose(spendTx)
                .withSigner(SignerProviders.signerFrom(sender1))
                .withSigner(SignerProviders.signerFrom(sender2))
                .preBalanceTx((txBuilderContext, transaction) -> {
                    transaction.getWitnessSet().getNativeScripts().add(multisigScript);
                })
                .completeAndWait(System.out::println);
    }
}