support nested wallets

src/main/java/com/sparrowwallet/drongo/bip47/PaymentCode.java

@@ -361,6 +361,10 @@ public class PaymentCode {
         return new PaymentCode(strPaymentCode, pubkey, chain);
     }
 
+    public String toAbbreviatedString() {
+        return strPaymentCode.substring(0, 8) + "..." + strPaymentCode.substring(strPaymentCode.length() - 3);
+    }
+
     @Override
     public boolean equals(Object o) {
         if(this == o) {

src/main/java/com/sparrowwallet/drongo/psbt/PSBT.java

@@ -18,6 +18,7 @@ import java.util.*;
 import static com.sparrowwallet.drongo.psbt.PSBTEntry.*;
 import static com.sparrowwallet.drongo.psbt.PSBTInput.*;
 import static com.sparrowwallet.drongo.psbt.PSBTOutput.*;
+import static com.sparrowwallet.drongo.wallet.Wallet.addDummySpendingInput;
 
 public class PSBT {
     public static final byte PSBT_GLOBAL_UNSIGNED_TX = 0x00;
@@ -89,12 +90,16 @@ public class PSBT {
             this.version = version;
         }
 
-        boolean alwaysIncludeWitnessUtxo = wallet.getKeystores().stream().anyMatch(keystore -> keystore.getWalletModel().alwaysIncludeNonWitnessUtxo());
-
         int inputIndex = 0;
         for(Iterator<Map.Entry<BlockTransactionHashIndex, WalletNode>> iter = walletTransaction.getSelectedUtxos().entrySet().iterator(); iter.hasNext(); inputIndex++) {
             Map.Entry<BlockTransactionHashIndex, WalletNode> utxoEntry = iter.next();
-            Transaction utxo = wallet.getTransactions().get(utxoEntry.getKey().getHash()).getTransaction();
+
+            WalletNode walletNode = utxoEntry.getValue();
+            Wallet signingWallet = walletNode.getWallet();
+
+            boolean alwaysIncludeWitnessUtxo = signingWallet.getKeystores().stream().anyMatch(keystore -> keystore.getWalletModel().alwaysIncludeNonWitnessUtxo());
+
+            Transaction utxo = signingWallet.getTransactions().get(utxoEntry.getKey().getHash()).getTransaction();
             int utxoIndex = (int)utxoEntry.getKey().getIndex();
             TransactionOutput utxoOutput = utxo.getOutputs().get(utxoIndex);
 
@@ -112,17 +117,16 @@ public class PSBT {
 
             Map<ECKey, KeyDerivation> derivedPublicKeys = new LinkedHashMap<>();
             ECKey tapInternalKey = null;
-            for(Keystore keystore : wallet.getKeystores()) {
+            for(Keystore keystore : signingWallet.getKeystores()) {
-                WalletNode walletNode = utxoEntry.getValue();
+                derivedPublicKeys.put(signingWallet.getScriptType().getOutputKey(keystore.getPubKey(walletNode)), keystore.getKeyDerivation().extend(walletNode.getDerivation()));
-                derivedPublicKeys.put(wallet.getScriptType().getOutputKey(keystore.getPubKey(walletNode)), keystore.getKeyDerivation().extend(walletNode.getDerivation()));
 
                 //TODO: Implement Musig for multisig wallets
-                if(wallet.getScriptType() == ScriptType.P2TR) {
+                if(signingWallet.getScriptType() == ScriptType.P2TR) {
                     tapInternalKey = keystore.getPubKey(walletNode);
                 }
             }
 
-            PSBTInput psbtInput = new PSBTInput(this, wallet.getScriptType(), transaction, inputIndex, utxo, utxoIndex, redeemScript, witnessScript, derivedPublicKeys, Collections.emptyMap(), tapInternalKey, alwaysIncludeWitnessUtxo);
+            PSBTInput psbtInput = new PSBTInput(this, signingWallet.getScriptType(), transaction, inputIndex, utxo, utxoIndex, redeemScript, witnessScript, derivedPublicKeys, Collections.emptyMap(), tapInternalKey, alwaysIncludeWitnessUtxo);
             psbtInputs.add(psbtInput);
         }
 
@@ -132,7 +136,7 @@ public class PSBT {
                 Address address = txOutput.getScript().getToAddresses()[0];
                 if(walletTransaction.getPayments().stream().anyMatch(payment -> payment.getAddress().equals(address))) {
                     outputNodes.add(wallet.getWalletAddresses().getOrDefault(address, null));
-                } else if(walletTransaction.getChangeMap().keySet().stream().anyMatch(changeNode -> wallet.getAddress(changeNode).equals(address))) {
+                } else if(walletTransaction.getChangeMap().keySet().stream().anyMatch(changeNode -> changeNode.getAddress().equals(address))) {
                     outputNodes.add(wallet.getWalletAddresses().getOrDefault(address, null));
                 }
             } catch(NonStandardScriptException e) {
@@ -151,7 +155,7 @@ public class PSBT {
 
                 //Construct dummy transaction to spend the UTXO created by this wallet's txOutput
                 Transaction transaction = new Transaction();
-                TransactionInput spendingInput = wallet.addDummySpendingInput(transaction, outputNode, txOutput);
+                TransactionInput spendingInput = addDummySpendingInput(transaction, outputNode, txOutput);
 
                 Script redeemScript = null;
                 if(ScriptType.P2SH.isScriptType(txOutput.getScript())) {
@@ -164,7 +168,7 @@ public class PSBT {
                 }
 
                 Map<ECKey, KeyDerivation> derivedPublicKeys = new LinkedHashMap<>();
-                for(Keystore keystore : wallet.getKeystores()) {
+                for(Keystore keystore : outputNode.getWallet().getKeystores()) {
                     derivedPublicKeys.put(keystore.getPubKey(outputNode), keystore.getKeyDerivation().extend(outputNode.getDerivation()));
                 }
 

src/main/java/com/sparrowwallet/drongo/psbt/PSBTInput.java

@@ -102,11 +102,7 @@ public class PSBTInput {
                         log.debug(" Transaction input references txid: " + input.getOutpoint().getHash() + " vout " + input.getOutpoint().getIndex() + " with script " + input.getScriptSig());
                     }
                     for(TransactionOutput output: nonWitnessTx.getOutputs()) {
-                        try {
+                        log.debug(" Transaction output value: " + output.getValue() + (output.getScript().getToAddress() != null ? " to address " + output.getScript().getToAddress() : "") + " with script hex " + Utils.bytesToHex(output.getScript().getProgram()) + " to script " + output.getScript());
-                            log.debug(" Transaction output value: " + output.getValue() + " to addresses " + Arrays.asList(output.getScript().getToAddresses()) + " with script hex " + Utils.bytesToHex(output.getScript().getProgram()) + " to script " + output.getScript());
-                        } catch(NonStandardScriptException e) {
-                            log.error("Unknown script type", e);
-                        }
                     }
                     break;
                 case PSBT_IN_WITNESS_UTXO:

src/main/java/com/sparrowwallet/drongo/wallet/CoinbaseUtxoFilter.java

@@ -12,7 +12,7 @@ public class CoinbaseUtxoFilter implements UtxoFilter {
     @Override
     public boolean isEligible(BlockTransactionHashIndex candidate) {
         //Disallow immature coinbase outputs
-        BlockTransaction blockTransaction = wallet.getTransactions().get(candidate.getHash());
+        BlockTransaction blockTransaction = wallet.getWalletTransaction(candidate.getHash());
         if(blockTransaction != null && blockTransaction.getTransaction() != null && blockTransaction.getTransaction().isCoinBase()
             && wallet.getStoredBlockHeight() != null && candidate.getConfirmations(wallet.getStoredBlockHeight()) < Transaction.COINBASE_MATURITY_THRESHOLD) {
             return false;

src/main/java/com/sparrowwallet/drongo/wallet/OutputGroup.java

@@ -1,5 +1,7 @@
 package com.sparrowwallet.drongo.wallet;
 
+import com.sparrowwallet.drongo.protocol.ScriptType;
+
 import java.util.ArrayList;
 import java.util.List;
 
@@ -7,6 +9,7 @@ import static com.sparrowwallet.drongo.protocol.Transaction.WITNESS_SCALE_FACTOR
 
 public class OutputGroup {
     private final List<BlockTransactionHashIndex> utxos = new ArrayList<>();
+    private final ScriptType scriptType;
     private final int walletBlockHeight;
     private final long inputWeightUnits;
     private final double feeRate;
@@ -18,7 +21,8 @@ public class OutputGroup {
     private int depth = Integer.MAX_VALUE;
     private boolean allInputsFromWallet = true;
 
-    public OutputGroup(int walletBlockHeight, long inputWeightUnits, double feeRate, double longTermFeeRate) {
+    public OutputGroup(ScriptType scriptType, int walletBlockHeight, long inputWeightUnits, double feeRate, double longTermFeeRate) {
+        this.scriptType = scriptType;
         this.walletBlockHeight = walletBlockHeight;
         this.inputWeightUnits = inputWeightUnits;
         this.feeRate = feeRate;
@@ -48,6 +52,10 @@ public class OutputGroup {
         return utxos;
     }
 
+    public ScriptType getScriptType() {
+        return scriptType;
+    }
+
     public long getValue() {
         return value;
     }

src/main/java/com/sparrowwallet/drongo/wallet/StonewallUtxoSelector.java

@@ -1,15 +1,19 @@
 package com.sparrowwallet.drongo.wallet;
 
+import com.sparrowwallet.drongo.protocol.ScriptType;
+
 import java.util.*;
 import java.util.stream.Collectors;
 
 public class StonewallUtxoSelector implements UtxoSelector {
+    private final ScriptType preferredScriptType;
     private final long noInputsFee;
 
     //Use the same seed so the UTXO selection is deterministic
     private final Random random = new Random(42);
 
-    public StonewallUtxoSelector(long noInputsFee) {
+    public StonewallUtxoSelector(ScriptType preferredScriptType, long noInputsFee) {
+        this.preferredScriptType = preferredScriptType;
         this.noInputsFee = noInputsFee;
     }
 
@@ -17,6 +21,16 @@ public class StonewallUtxoSelector implements UtxoSelector {
     public List<Collection<BlockTransactionHashIndex>> selectSets(long targetValue, Collection<OutputGroup> candidates) {
         long actualTargetValue = targetValue + noInputsFee;
 
+        List<OutputGroup> preferredCandidates = candidates.stream().filter(outputGroup -> outputGroup.getScriptType().equals(preferredScriptType)).collect(Collectors.toList());
+        List<Collection<BlockTransactionHashIndex>> preferredSets = selectSets(targetValue, preferredCandidates, actualTargetValue);
+        if(!preferredSets.isEmpty()) {
+            return preferredSets;
+        }
+
+        return selectSets(targetValue, candidates, actualTargetValue);
+    }
+
+    private List<Collection<BlockTransactionHashIndex>> selectSets(long targetValue, Collection<OutputGroup> candidates, long actualTargetValue) {
         for(int i = 0; i < 10; i++) {
             List<OutputGroup> randomized = new ArrayList<>(candidates);
             Collections.shuffle(randomized, random);

src/main/java/com/sparrowwallet/drongo/wallet/Wallet.java

@@ -117,6 +117,7 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
         childWallet.purposeNodes.clear();
         childWallet.transactions.clear();
         childWallet.detachedLabels.clear();
+        childWallet.childWallets.clear();
         childWallet.storedBlockHeight = null;
         childWallet.gapLimit = standardAccount.getMinimumGapLimit();
         childWallet.birthDate = null;
@@ -156,9 +157,11 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
 
     public Wallet getChildWallet(StandardAccount account) {
         for(Wallet childWallet : getChildWallets()) {
-            for(Keystore keystore : childWallet.getKeystores()) {
+            if(!childWallet.isNested()) {
-                if(keystore.getKeyDerivation().getDerivation().get(keystore.getKeyDerivation().getDerivation().size() - 1).equals(account.getChildNumber())) {
+                for(Keystore keystore : childWallet.getKeystores()) {
-                    return childWallet;
+                    if(keystore.getKeyDerivation().getDerivation().get(keystore.getKeyDerivation().getDerivation().size() - 1).equals(account.getChildNumber())) {
+                        return childWallet;
+                    }
                 }
             }
         }
@@ -229,7 +232,12 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
         List<Wallet> allWallets = new ArrayList<>();
         Wallet masterWallet = isMasterWallet() ? this : getMasterWallet();
         allWallets.add(masterWallet);
-        allWallets.addAll(masterWallet.getChildWallets());
+        for(Wallet childWallet : getChildWallets()) {
+            if(!childWallet.isNested()) {
+                allWallets.add(childWallet);
+            }
+        }
+
         return allWallets;
     }
 
@@ -274,7 +282,7 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
         Address notificationAddress = externalPaymentCode.getNotificationAddress();
         for(Map.Entry<BlockTransactionHashIndex, WalletNode> txoEntry : getWalletTxos().entrySet()) {
             if(txoEntry.getKey().isSpent()) {
-                BlockTransaction blockTransaction = transactions.get(txoEntry.getKey().getSpentBy().getHash());
+                BlockTransaction blockTransaction = getWalletTransaction(txoEntry.getKey().getSpentBy().getHash());
                 if(blockTransaction != null) {
                     for(TransactionOutput txOutput : blockTransaction.getTransaction().getOutputs()) {
                         if(notificationAddress.equals(txOutput.getScript().getToAddress())) {
@@ -293,6 +301,10 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
         return Collections.emptyMap();
     }
 
+    public boolean isNested() {
+        return isBip47();
+    }
+
     public boolean isBip47() {
         return !isMasterWallet() && getKeystores().size() == 1 && getKeystores().get(0).getSource() == KeystoreSource.SW_PAYMENT_CODE;
     }
@@ -329,7 +341,9 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
 
         Set<StandardAccount> whirlpoolAccounts = new HashSet<>(Set.of(StandardAccount.WHIRLPOOL_PREMIX, StandardAccount.WHIRLPOOL_POSTMIX, StandardAccount.WHIRLPOOL_BADBANK));
         for(Wallet childWallet : getChildWallets()) {
-            whirlpoolAccounts.remove(childWallet.getStandardAccountType());
+            if(!childWallet.isNested()) {
+                whirlpoolAccounts.remove(childWallet.getStandardAccountType());
+            }
         }
 
         return whirlpoolAccounts.isEmpty();
@@ -525,7 +539,7 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
         WalletNode purposeNode;
         Optional<WalletNode> optionalPurposeNode = purposeNodes.stream().filter(node -> node.getKeyPurpose().equals(keyPurpose)).findFirst();
         if(optionalPurposeNode.isEmpty()) {
-            purposeNode = new WalletNode(keyPurpose);
+            purposeNode = new WalletNode(this, keyPurpose);
             purposeNodes.add(purposeNode);
         } else {
             purposeNode = optionalPurposeNode.get();
@@ -598,10 +612,10 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
 
     public Address getAddress(WalletNode node) {
         if(policyType == PolicyType.SINGLE) {
-            ECKey pubKey = getPubKey(node);
+            ECKey pubKey = node.getPubKey();
             return scriptType.getAddress(pubKey);
         } else if(policyType == PolicyType.MULTI) {
-            List<ECKey> pubKeys = getPubKeys(node);
+            List<ECKey> pubKeys = node.getPubKeys();
             Script script = ScriptType.MULTISIG.getOutputScript(defaultPolicy.getNumSignaturesRequired(), pubKeys);
             return scriptType.getAddress(script);
         } else {
@@ -611,10 +625,10 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
 
     public Script getOutputScript(WalletNode node) {
         if(policyType == PolicyType.SINGLE) {
-            ECKey pubKey = getPubKey(node);
+            ECKey pubKey = node.getPubKey();
             return scriptType.getOutputScript(pubKey);
         } else if(policyType == PolicyType.MULTI) {
-            List<ECKey> pubKeys = getPubKeys(node);
+            List<ECKey> pubKeys = node.getPubKeys();
             Script script = ScriptType.MULTISIG.getOutputScript(defaultPolicy.getNumSignaturesRequired(), pubKeys);
             return scriptType.getOutputScript(script);
         } else {
@@ -624,10 +638,10 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
 
     public String getOutputDescriptor(WalletNode node) {
         if(policyType == PolicyType.SINGLE) {
-            ECKey pubKey = getPubKey(node);
+            ECKey pubKey = node.getPubKey();
             return scriptType.getOutputDescriptor(pubKey);
         } else if(policyType == PolicyType.MULTI) {
-            List<ECKey> pubKeys = getPubKeys(node);
+            List<ECKey> pubKeys = node.getPubKeys();
             Script script = ScriptType.MULTISIG.getOutputScript(defaultPolicy.getNumSignaturesRequired(), pubKeys);
             return scriptType.getOutputDescriptor(script);
         } else {
@@ -662,12 +676,20 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
             getWalletAddresses(walletAddresses, getNode(keyPurpose));
         }
 
+        for(Wallet childWallet : getChildWallets()) {
+            if(childWallet.isNested()) {
+                for(KeyPurpose keyPurpose : childWallet.getWalletKeyPurposes()) {
+                    getWalletAddresses(walletAddresses, childWallet.getNode(keyPurpose));
+                }
+            }
+        }
+
         return walletAddresses;
     }
 
     private void getWalletAddresses(Map<Address, WalletNode> walletAddresses, WalletNode purposeNode) {
         for(WalletNode addressNode : purposeNode.getChildren()) {
-            walletAddresses.put(getAddress(addressNode), addressNode);
+            walletAddresses.put(addressNode.getAddress(), addressNode);
         }
     }
 
@@ -692,12 +714,23 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
         for(KeyPurpose keyPurpose : keyPurposes) {
             getWalletOutputScripts(walletOutputScripts, getNode(keyPurpose));
         }
+
+        for(Wallet childWallet : getChildWallets()) {
+            if(childWallet.isNested()) {
+                for(KeyPurpose keyPurpose : childWallet.getWalletKeyPurposes()) {
+                    if(keyPurposes.contains(keyPurpose)) {
+                        getWalletOutputScripts(walletOutputScripts, childWallet.getNode(keyPurpose));
+                    }
+                }
+            }
+        }
+
         return walletOutputScripts;
     }
 
     private void getWalletOutputScripts(Map<Script, WalletNode> walletOutputScripts, WalletNode purposeNode) {
         for(WalletNode addressNode : purposeNode.getChildren()) {
-            walletOutputScripts.put(getOutputScript(addressNode), addressNode);
+            walletOutputScripts.put(addressNode.getOutputScript(), addressNode);
         }
     }
 
@@ -719,6 +752,14 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
             getWalletTxos(walletTxos, getNode(keyPurpose));
         }
 
+        for(Wallet childWallet : getChildWallets()) {
+            if(childWallet.isNested()) {
+                for(KeyPurpose keyPurpose : childWallet.getWalletKeyPurposes()) {
+                    getWalletTxos(walletTxos, childWallet.getNode(keyPurpose));
+                }
+            }
+        }
+
         return walletTxos;
     }
 
@@ -740,6 +781,14 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
             getWalletUtxos(walletUtxos, getNode(keyPurpose), includeSpentMempoolOutputs);
         }
 
+        for(Wallet childWallet : getChildWallets()) {
+            if(childWallet.isNested()) {
+                for(KeyPurpose keyPurpose : childWallet.getWalletKeyPurposes()) {
+                    getWalletUtxos(walletUtxos, childWallet.getNode(keyPurpose), includeSpentMempoolOutputs);
+                }
+            }
+        }
+
         return walletUtxos;
     }
 
@@ -751,6 +800,51 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
         }
     }
 
+    public boolean hasTransactions() {
+        if(!transactions.isEmpty()) {
+            return true;
+        }
+
+        for(Wallet childWallet : getChildWallets()) {
+            if(childWallet.isNested()) {
+                if(!childWallet.transactions.isEmpty()) {
+                    return true;
+                }
+            }
+        }
+
+        return false;
+    }
+
+    public BlockTransaction getWalletTransaction(Sha256Hash txid) {
+        BlockTransaction blockTransaction = transactions.get(txid);
+        if(blockTransaction != null) {
+            return blockTransaction;
+        }
+
+        for(Wallet childWallet : getChildWallets()) {
+            if(childWallet.isNested()) {
+                blockTransaction = childWallet.transactions.get(txid);
+                if(blockTransaction != null) {
+                    return blockTransaction;
+                }
+            }
+        }
+
+        return null;
+    }
+
+    public Map<Sha256Hash, BlockTransaction> getWalletTransactions() {
+        Map<Sha256Hash, BlockTransaction> allTransactions = new HashMap<>(transactions);
+        for(Wallet childWallet : getChildWallets()) {
+            if(childWallet.isNested()) {
+                allTransactions.putAll(childWallet.transactions);
+            }
+        }
+
+        return allTransactions;
+    }
+
     /**
      * Determines the dust threshold for creating a new change output in this wallet.
      *
@@ -828,15 +922,15 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
         WalletNode receiveNode = getFreshNode(KeyPurpose.RECEIVE);
 
         Transaction transaction = new Transaction();
-        TransactionOutput prevTxOut = transaction.addOutput(1L, getAddress(receiveNode));
+        TransactionOutput prevTxOut = transaction.addOutput(1L, receiveNode.getAddress());
 
         TransactionInput txInput = null;
         if(getPolicyType().equals(PolicyType.SINGLE)) {
-            ECKey pubKey = getPubKey(receiveNode);
+            ECKey pubKey = receiveNode.getPubKey();
             TransactionSignature signature = TransactionSignature.dummy(getScriptType().getSignatureType());
             txInput = getScriptType().addSpendingInput(transaction, prevTxOut, pubKey, signature);
         } else if(getPolicyType().equals(PolicyType.MULTI)) {
-            List<ECKey> pubKeys = getPubKeys(receiveNode);
+            List<ECKey> pubKeys = receiveNode.getPubKeys();
             int threshold = getDefaultPolicy().getNumSignaturesRequired();
             Map<ECKey, TransactionSignature> pubKeySignatures = new TreeMap<>(new ECKey.LexicographicECKeyComparator());
             for(int i = 0; i < pubKeys.size(); i++) {
@@ -856,7 +950,7 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
 
     public long getCostOfChange(double feeRate, double longTermFeeRate) {
         WalletNode changeNode = getFreshNode(KeyPurpose.CHANGE);
-        TransactionOutput changeOutput = new TransactionOutput(new Transaction(), 1L, getOutputScript(changeNode));
+        TransactionOutput changeOutput = new TransactionOutput(new Transaction(), 1L, changeNode.getOutputScript());
         return getFee(changeOutput, feeRate, longTermFeeRate);
     }
 
@@ -898,7 +992,7 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
 
             //Add inputs
             for(Map.Entry<BlockTransactionHashIndex, WalletNode> selectedUtxo : selectedUtxos.entrySet()) {
-                Transaction prevTx = getTransactions().get(selectedUtxo.getKey().getHash()).getTransaction();
+                Transaction prevTx = getWalletTransaction(selectedUtxo.getKey().getHash()).getTransaction();
                 TransactionOutput prevTxOut = prevTx.getOutputs().get((int)selectedUtxo.getKey().getIndex());
                 TransactionInput txInput = addDummySpendingInput(transaction, selectedUtxo.getValue(), prevTxOut);
 
@@ -913,7 +1007,7 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
             for(int i = 1; i < numSets; i+=2) {
                 WalletNode mixNode = getFreshNode(getChangeKeyPurpose());
                 txExcludedChangeNodes.add(mixNode);
-                Payment fakeMixPayment = new Payment(getAddress(mixNode), ".." + mixNode + " (Fake Mix)", totalPaymentAmount, false);
+                Payment fakeMixPayment = new Payment(mixNode.getAddress(), ".." + mixNode + " (Fake Mix)", totalPaymentAmount, false);
                 fakeMixPayment.setType(Payment.Type.FAKE_MIX);
                 txPayments.add(fakeMixPayment);
             }
@@ -972,7 +1066,7 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
                 while(txExcludedChangeNodes.contains(changeNode)) {
                     changeNode = getFreshNode(getChangeKeyPurpose(), changeNode);
                 }
-                TransactionOutput changeOutput = new TransactionOutput(transaction, setChangeAmts.iterator().next(), getOutputScript(changeNode));
+                TransactionOutput changeOutput = new TransactionOutput(transaction, setChangeAmts.iterator().next(), changeNode.getOutputScript());
                 double changeVSize = noChangeVSize + changeOutput.getLength() * numSets;
                 long changeFeeRequiredAmt = (fee == null ? (long)Math.floor(feeRate * changeVSize) : fee);
                 changeFeeRequiredAmt = (fee == null && feeRate == Transaction.DEFAULT_MIN_RELAY_FEE ? changeFeeRequiredAmt + 1 : changeFeeRequiredAmt);
@@ -984,7 +1078,7 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
                 Map<WalletNode, Long> changeMap = new LinkedHashMap<>();
                 setChangeAmts = getSetChangeAmounts(selectedUtxoSets, totalPaymentAmount, changeFeeRequiredAmt);
                 for(Long setChangeAmt : setChangeAmts) {
-                    transaction.addOutput(setChangeAmt, getOutputScript(changeNode));
+                    transaction.addOutput(setChangeAmt, changeNode.getOutputScript());
                     changeMap.put(changeNode, setChangeAmt);
                     changeNode = getFreshNode(getChangeKeyPurpose(), changeNode);
                 }
@@ -1041,20 +1135,21 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
         return changeAmts;
     }
 
-    public TransactionInput addDummySpendingInput(Transaction transaction, WalletNode walletNode, TransactionOutput prevTxOut) {
+    public static TransactionInput addDummySpendingInput(Transaction transaction, WalletNode walletNode, TransactionOutput prevTxOut) {
-        if(getPolicyType().equals(PolicyType.SINGLE)) {
+        Wallet signingWallet = walletNode.getWallet();
-            ECKey pubKey = getPubKey(walletNode);
+        if(signingWallet.getPolicyType().equals(PolicyType.SINGLE)) {
-            return getScriptType().addSpendingInput(transaction, prevTxOut, pubKey, TransactionSignature.dummy(getScriptType().getSignatureType()));
+            ECKey pubKey = walletNode.getPubKey();
-        } else if(getPolicyType().equals(PolicyType.MULTI)) {
+            return signingWallet.getScriptType().addSpendingInput(transaction, prevTxOut, pubKey, TransactionSignature.dummy(signingWallet.getScriptType().getSignatureType()));
-            List<ECKey> pubKeys = getPubKeys(walletNode);
+        } else if(signingWallet.getPolicyType().equals(PolicyType.MULTI)) {
-            int threshold = getDefaultPolicy().getNumSignaturesRequired();
+            List<ECKey> pubKeys = walletNode.getPubKeys();
+            int threshold = signingWallet.getDefaultPolicy().getNumSignaturesRequired();
             Map<ECKey, TransactionSignature> pubKeySignatures = new TreeMap<>(new ECKey.LexicographicECKeyComparator());
             for(int i = 0; i < pubKeys.size(); i++) {
-                pubKeySignatures.put(pubKeys.get(i), i < threshold ? TransactionSignature.dummy(getScriptType().getSignatureType()) : null);
+                pubKeySignatures.put(pubKeys.get(i), i < threshold ? TransactionSignature.dummy(signingWallet.getScriptType().getSignatureType()) : null);
             }
-            return getScriptType().addMultisigSpendingInput(transaction, prevTxOut, threshold, pubKeySignatures);
+            return signingWallet.getScriptType().addMultisigSpendingInput(transaction, prevTxOut, threshold, pubKeySignatures);
         } else {
-            throw new UnsupportedOperationException("Cannot create transaction for policy type " + getPolicyType());
+            throw new UnsupportedOperationException("Cannot create transaction for policy type " + signingWallet.getPolicyType());
         }
     }
 
@@ -1104,14 +1199,23 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
 
     private List<OutputGroup> getGroupedUtxos(List<UtxoFilter> utxoFilters, double feeRate, double longTermFeeRate, boolean groupByAddress, boolean includeSpentMempoolOutputs) {
         List<OutputGroup> outputGroups = new ArrayList<>();
+        Map<Sha256Hash, BlockTransaction> walletTransactions = getWalletTransactions();
         for(KeyPurpose keyPurpose : getWalletKeyPurposes()) {
-            getGroupedUtxos(outputGroups, getNode(keyPurpose), utxoFilters, feeRate, longTermFeeRate, groupByAddress, includeSpentMempoolOutputs);
+            getGroupedUtxos(outputGroups, getNode(keyPurpose), utxoFilters, walletTransactions, feeRate, longTermFeeRate, groupByAddress, includeSpentMempoolOutputs);
+        }
+
+        for(Wallet childWallet : getChildWallets()) {
+            if(childWallet.isNested()) {
+                for(KeyPurpose keyPurpose : childWallet.getWalletKeyPurposes()) {
+                    childWallet.getGroupedUtxos(outputGroups, childWallet.getNode(keyPurpose), utxoFilters, walletTransactions, feeRate, longTermFeeRate, groupByAddress, includeSpentMempoolOutputs);
+                }
+            }
         }
 
         return outputGroups;
     }
 
-    private void getGroupedUtxos(List<OutputGroup> outputGroups, WalletNode purposeNode, List<UtxoFilter> utxoFilters, double feeRate, double longTermFeeRate, boolean groupByAddress, boolean includeSpentMempoolOutputs) {
+    private void getGroupedUtxos(List<OutputGroup> outputGroups, WalletNode purposeNode, List<UtxoFilter> utxoFilters, Map<Sha256Hash, BlockTransaction> walletTransactions, double feeRate, double longTermFeeRate, boolean groupByAddress, boolean includeSpentMempoolOutputs) {
         for(WalletNode addressNode : purposeNode.getChildren()) {
             OutputGroup outputGroup = null;
             for(BlockTransactionHashIndex utxo : addressNode.getUnspentTransactionOutputs(includeSpentMempoolOutputs)) {
@@ -1121,11 +1225,11 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
                 }
 
                 if(outputGroup == null || !groupByAddress) {
-                    outputGroup = new OutputGroup(getStoredBlockHeight(), getInputWeightUnits(), feeRate, longTermFeeRate);
+                    outputGroup = new OutputGroup(addressNode.getWallet().getScriptType(), getStoredBlockHeight(), getInputWeightUnits(), feeRate, longTermFeeRate);
                     outputGroups.add(outputGroup);
                 }
 
-                outputGroup.add(utxo, allInputsFromWallet(utxo.getHash()));
+                outputGroup.add(utxo, allInputsFromWallet(walletTransactions, utxo.getHash()));
             }
         }
     }
@@ -1137,7 +1241,12 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
      * @return Whether the transaction was created entirely from inputs that reference outputs that belong to this wallet
      */
     public boolean allInputsFromWallet(Sha256Hash txId) {
-        BlockTransaction utxoBlkTx = getTransactions().get(txId);
+        Map<Sha256Hash, BlockTransaction> allTransactions = getWalletTransactions();
+        return allInputsFromWallet(allTransactions, txId);
+    }
+
+    private boolean allInputsFromWallet(Map<Sha256Hash, BlockTransaction> walletTransactions, Sha256Hash txId) {
+        BlockTransaction utxoBlkTx = walletTransactions.get(txId);
         if(utxoBlkTx == null) {
             //Provided txId was not a wallet transaction
             return false;
@@ -1145,7 +1254,7 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
 
         for(int i = 0; i < utxoBlkTx.getTransaction().getInputs().size(); i++) {
             TransactionInput utxoTxInput = utxoBlkTx.getTransaction().getInputs().get(i);
-            BlockTransaction prevBlkTx = getTransactions().get(utxoTxInput.getOutpoint().getHash());
+            BlockTransaction prevBlkTx = walletTransactions.get(utxoTxInput.getOutpoint().getHash());
             if(prevBlkTx == null) {
                 return false;
             }
@@ -1171,13 +1280,13 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
      */
     public long getMaxSpendable(List<Address> paymentAddresses, double feeRate) {
         long maxInputValue = 0;
-        int inputWeightUnits = getInputWeightUnits();
-        long minInputValue = (long)Math.ceil(feeRate * inputWeightUnits / WITNESS_SCALE_FACTOR);
 
         Transaction transaction = new Transaction();
         for(Map.Entry<BlockTransactionHashIndex, WalletNode> utxo : getWalletUtxos().entrySet()) {
+            int inputWeightUnits = utxo.getValue().getWallet().getInputWeightUnits();
+            long minInputValue = (long)Math.ceil(feeRate * inputWeightUnits / WITNESS_SCALE_FACTOR);
             if(utxo.getKey().getValue() > minInputValue) {
-                Transaction prevTx = getTransactions().get(utxo.getKey().getHash()).getTransaction();
+                Transaction prevTx = getWalletTransaction(utxo.getKey().getHash()).getTransaction();
                 TransactionOutput prevTxOut = prevTx.getOutputs().get((int)utxo.getKey().getIndex());
                 addDummySpendingInput(transaction, utxo.getValue(), prevTxOut);
                 maxInputValue += utxo.getKey().getValue();
@@ -1207,7 +1316,7 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
         Map<Script, WalletNode> walletOutputScripts = getWalletOutputScripts();
 
         for(TransactionInput txInput : transaction.getInputs()) {
-            BlockTransaction blockTransaction = transactions.get(txInput.getOutpoint().getHash());
+            BlockTransaction blockTransaction = getWalletTransaction(txInput.getOutpoint().getHash());
             if(blockTransaction != null && blockTransaction.getTransaction().getOutputs().size() > txInput.getOutpoint().getIndex()) {
                 TransactionOutput utxo = blockTransaction.getTransaction().getOutputs().get((int)txInput.getOutpoint().getIndex());
 
@@ -1236,20 +1345,22 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
 
         for(TransactionInput txInput : signingNodes.keySet()) {
             WalletNode walletNode = signingNodes.get(txInput);
-            Map<ECKey, Keystore> keystoreKeysForNode = getKeystores().stream().collect(Collectors.toMap(keystore -> getScriptType().getOutputKey(keystore.getPubKey(walletNode)), Function.identity(),
+            Wallet signingWallet = walletNode.getWallet();
+            Map<ECKey, Keystore> keystoreKeysForNode = signingWallet.getKeystores().stream()
+                    .collect(Collectors.toMap(keystore -> signingWallet.getScriptType().getOutputKey(keystore.getPubKey(walletNode)), Function.identity(),
                     (u, v) -> { throw new IllegalStateException("Duplicate keys from different keystores for node " + walletNode); },
                     LinkedHashMap::new));
 
             Map<ECKey, TransactionSignature> keySignatureMap = new LinkedHashMap<>();
 
-            BlockTransaction blockTransaction = transactions.get(txInput.getOutpoint().getHash());
+            BlockTransaction blockTransaction = signingWallet.transactions.get(txInput.getOutpoint().getHash());
             if(blockTransaction != null && blockTransaction.getTransaction().getOutputs().size() > txInput.getOutpoint().getIndex()) {
                 TransactionOutput spentTxo = blockTransaction.getTransaction().getOutputs().get((int)txInput.getOutpoint().getIndex());
 
                 Script signingScript = getSigningScript(txInput, spentTxo);
                 Sha256Hash hash;
-                if(getScriptType() == P2TR) {
+                if(signingWallet.getScriptType() == P2TR) {
-                    List<TransactionOutput> spentOutputs = transaction.getInputs().stream().map(input -> transactions.get(input.getOutpoint().getHash()).getTransaction().getOutputs().get((int)input.getOutpoint().getIndex())).collect(Collectors.toList());
+                    List<TransactionOutput> spentOutputs = transaction.getInputs().stream().map(input -> signingWallet.transactions.get(input.getOutpoint().getHash()).getTransaction().getOutputs().get((int)input.getOutpoint().getIndex())).collect(Collectors.toList());
                     hash = transaction.hashForTaprootSignature(spentOutputs, txInput.getIndex(), !P2TR.isScriptType(signingScript), signingScript, SigHash.ALL_TAPROOT, null);
                 } else if(txInput.hasWitness()) {
                     hash = transaction.hashForWitnessSignature(txInput.getIndex(), signingScript, spentTxo.getValue(), SigHash.ALL);
@@ -1336,7 +1447,9 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
 
         for(PSBTInput psbtInput : signingNodes.keySet()) {
             WalletNode walletNode = signingNodes.get(psbtInput);
-            Map<ECKey, Keystore> keystoreKeysForNode = getKeystores().stream().collect(Collectors.toMap(keystore -> getScriptType().getOutputKey(keystore.getPubKey(walletNode)), Function.identity(),
+            Wallet signingWallet = walletNode.getWallet();
+            Map<ECKey, Keystore> keystoreKeysForNode = signingWallet.getKeystores().stream()
+                    .collect(Collectors.toMap(keystore -> signingWallet.getScriptType().getOutputKey(keystore.getPubKey(walletNode)), Function.identity(),
                     (u, v) -> { throw new IllegalStateException("Duplicate keys from different keystores for node " + walletNode); },
                     LinkedHashMap::new));
 
@@ -1362,10 +1475,11 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
 
     public void sign(PSBT psbt) throws MnemonicException {
         Map<PSBTInput, WalletNode> signingNodes = getSigningNodes(psbt);
-        for(Keystore keystore : getKeystores()) {
+        for(Map.Entry<PSBTInput, WalletNode> signingEntry : signingNodes.entrySet()) {
-            if(keystore.hasPrivateKey()) {
+            Wallet signingWallet = signingEntry.getValue().getWallet();
-                for(Map.Entry<PSBTInput, WalletNode> signingEntry : signingNodes.entrySet()) {
+            for(Keystore keystore : signingWallet.getKeystores()) {
-                    ECKey privKey = getScriptType().getOutputKey(keystore.getKey(signingEntry.getValue()));
+                if(keystore.hasPrivateKey()) {
+                    ECKey privKey = signingWallet.getScriptType().getOutputKey(keystore.getKey(signingEntry.getValue()));
                     PSBTInput psbtInput = signingEntry.getKey();
 
                     if(!psbtInput.isSigned()) {
@@ -1410,15 +1524,15 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
 
                 TransactionInput finalizedTxInput;
                 if(getPolicyType().equals(PolicyType.SINGLE)) {
-                    ECKey pubKey = getPubKey(signingNode);
+                    ECKey pubKey = signingNode.getPubKey();
                     TransactionSignature transactionSignature = psbtInput.isTaproot() ? psbtInput.getTapKeyPathSignature() : psbtInput.getPartialSignature(pubKey);
                     if(transactionSignature == null) {
                         throw new IllegalArgumentException("Pubkey of partial signature does not match wallet pubkey");
                     }
 
-                    finalizedTxInput = getScriptType().addSpendingInput(transaction, utxo, pubKey, transactionSignature);
+                    finalizedTxInput = signingNode.getWallet().getScriptType().addSpendingInput(transaction, utxo, pubKey, transactionSignature);
                 } else if(getPolicyType().equals(PolicyType.MULTI)) {
-                    List<ECKey> pubKeys = getPubKeys(signingNode);
+                    List<ECKey> pubKeys = signingNode.getPubKeys();
 
                     Map<ECKey, TransactionSignature> pubKeySignatures = new TreeMap<>(new ECKey.LexicographicECKeyComparator());
                     for(ECKey pubKey : pubKeys) {
@@ -1430,7 +1544,7 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
                         throw new IllegalArgumentException("Pubkeys of partial signatures do not match wallet pubkeys");
                     }
 
-                    finalizedTxInput = getScriptType().addMultisigSpendingInput(transaction, utxo, threshold, pubKeySignatures);
+                    finalizedTxInput = signingNode.getWallet().getScriptType().addMultisigSpendingInput(transaction, utxo, threshold, pubKeySignatures);
                 } else {
                     throw new UnsupportedOperationException("Cannot finalise PSBT for policy type " + getPolicyType());
                 }
@@ -1471,6 +1585,12 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
 
         transactions.clear();
         storedBlockHeight = 0;
+
+        for(Wallet childWallet : getChildWallets()) {
+            if(childWallet.isNested()) {
+                childWallet.clearHistory();
+            }
+        }
     }
 
     private Map<String, String> getDetachedLabels(boolean includeAddresses) {
@@ -1484,7 +1604,7 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
         for(WalletNode purposeNode : purposeNodes) {
             for(WalletNode addressNode : purposeNode.getChildren()) {
                 if(includeAddresses && addressNode.getLabel() != null && !addressNode.getLabel().isEmpty()) {
-                    labels.put(getAddress(addressNode).toString(), addressNode.getLabel());
+                    labels.put(addressNode.getAddress().toString(), addressNode.getLabel());
                 }
 
                 for(BlockTransactionHashIndex output : addressNode.getTransactionOutputs()) {
@@ -1637,7 +1757,7 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
             copy.getKeystores().add(keystore.copy());
         }
         for(WalletNode node : purposeNodes) {
-            copy.purposeNodes.add(node.copy());
+            copy.purposeNodes.add(node.copy(copy));
         }
         for(Sha256Hash hash : transactions.keySet()) {
             copy.transactions.put(hash, transactions.get(hash));
@@ -1684,6 +1804,12 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
             }
         }
 
+        for(Wallet childWallet : getChildWallets()) {
+            if(childWallet.isNested() && childWallet.isEncrypted()) {
+                return true;
+            }
+        }
+
         return false;
     }
 
@@ -1691,24 +1817,48 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
         for(Keystore keystore : keystores) {
             keystore.encrypt(key);
         }
+
+        for(Wallet childWallet : getChildWallets()) {
+            if(childWallet.isNested()) {
+                childWallet.encrypt(key);
+            }
+        }
     }
 
     public void decrypt(CharSequence password) {
         for(Keystore keystore : keystores) {
             keystore.decrypt(password);
         }
+
+        for(Wallet childWallet : getChildWallets()) {
+            if(childWallet.isNested()) {
+                childWallet.decrypt(password);
+            }
+        }
     }
 
     public void decrypt(Key key) {
         for(Keystore keystore : keystores) {
             keystore.decrypt(key);
         }
+
+        for(Wallet childWallet : getChildWallets()) {
+            if(childWallet.isNested()) {
+                childWallet.decrypt(key);
+            }
+        }
     }
 
     public void clearPrivate() {
         for(Keystore keystore : keystores) {
             keystore.clearPrivate();
         }
+
+        for(Wallet childWallet : getChildWallets()) {
+            if(childWallet.isNested()) {
+                childWallet.clearPrivate();
+            }
+        }
     }
 
     @Override

src/main/java/com/sparrowwallet/drongo/wallet/WalletNode.java

@@ -2,7 +2,10 @@ package com.sparrowwallet.drongo.wallet;
 
 import com.sparrowwallet.drongo.KeyDerivation;
 import com.sparrowwallet.drongo.KeyPurpose;
+import com.sparrowwallet.drongo.address.Address;
 import com.sparrowwallet.drongo.crypto.ChildNumber;
+import com.sparrowwallet.drongo.crypto.ECKey;
+import com.sparrowwallet.drongo.protocol.Script;
 
 import java.util.*;
 import java.util.stream.Collectors;
@@ -13,29 +16,53 @@ public class WalletNode extends Persistable implements Comparable<WalletNode> {
     private TreeSet<WalletNode> children = new TreeSet<>();
     private TreeSet<BlockTransactionHashIndex> transactionOutputs = new TreeSet<>();
 
+    private transient Wallet wallet;
     private transient KeyPurpose keyPurpose;
     private transient int index = -1;
     private transient List<ChildNumber> derivation;
 
+    //Cache pubkeys for BIP47 wallets to avoid time-consuming ECDH calculations
+    private transient ECKey cachedPubKey;
+
+    //Note use of this constructor must be followed by setting the wallet field
     public WalletNode(String derivationPath) {
         this.derivationPath = derivationPath;
         parseDerivation();
     }
 
-    public WalletNode(KeyPurpose keyPurpose) {
+    public WalletNode(Wallet wallet, String derivationPath) {
+        this.wallet = wallet;
+        this.derivationPath = derivationPath;
+        parseDerivation();
+    }
+
+    public WalletNode(Wallet wallet, KeyPurpose keyPurpose) {
+        this.wallet = wallet;
         this.derivation = List.of(keyPurpose.getPathIndex());
         this.derivationPath = KeyDerivation.writePath(derivation);
         this.keyPurpose = keyPurpose;
         this.index = keyPurpose.getPathIndex().num();
     }
 
-    public WalletNode(KeyPurpose keyPurpose, int index) {
+    public WalletNode(Wallet wallet, KeyPurpose keyPurpose, int index) {
+        this.wallet = wallet;
         this.derivation = List.of(keyPurpose.getPathIndex(), new ChildNumber(index));
         this.derivationPath = KeyDerivation.writePath(derivation);
         this.keyPurpose = keyPurpose;
         this.index = index;
     }
 
+    public Wallet getWallet() {
+        return wallet;
+    }
+
+    public void setWallet(Wallet wallet) {
+        this.wallet = wallet;
+        for(WalletNode childNode : getChildren()) {
+            childNode.setWallet(wallet);
+        }
+    }
+
     public String getDerivationPath() {
         return derivationPath;
     }
@@ -154,7 +181,7 @@ public class WalletNode extends Persistable implements Comparable<WalletNode> {
         Set<WalletNode> newNodes = fillToIndex(index);
         if(!wallet.getDetachedLabels().isEmpty() && wallet.isValid()) {
             for(WalletNode newNode : newNodes) {
-                String label = wallet.getDetachedLabels().remove(wallet.getAddress(newNode).toString());
+                String label = wallet.getDetachedLabels().remove(newNode.getAddress().toString());
                 if(label != null && (newNode.getLabel() == null || newNode.getLabel().isEmpty())) {
                     newNode.setLabel(label);
                 }
@@ -167,7 +194,7 @@ public class WalletNode extends Persistable implements Comparable<WalletNode> {
     public synchronized Set<WalletNode> fillToIndex(int index) {
         Set<WalletNode> newNodes = new TreeSet<>();
         for(int i = 0; i <= index; i++) {
-            WalletNode node = new WalletNode(getKeyPurpose(), i);
+            WalletNode node = new WalletNode(wallet, getKeyPurpose(), i);
             if(children.add(node)) {
                 newNodes.add(node);
             }
@@ -190,6 +217,35 @@ public class WalletNode extends Persistable implements Comparable<WalletNode> {
         return highestNode == null ? null : highestNode.index;
     }
 
+    public ECKey getPubKey() {
+        if(cachedPubKey != null) {
+            return cachedPubKey;
+        }
+
+        if(wallet.isBip47()) {
+            cachedPubKey = wallet.getPubKey(this);
+            return cachedPubKey;
+        }
+
+        return wallet.getPubKey(this);
+    }
+
+    public List<ECKey> getPubKeys() {
+        return wallet.getPubKeys(this);
+    }
+
+    public Address getAddress() {
+        return wallet.getAddress(this);
+    }
+
+    public Script getOutputScript() {
+        return wallet.getOutputScript(this);
+    }
+
+    public String getOutputDescriptor() {
+        return wallet.getOutputDescriptor(this);
+    }
+
     @Override
     public String toString() {
         return derivationPath.replace("m", "..");
@@ -200,12 +256,12 @@ public class WalletNode extends Persistable implements Comparable<WalletNode> {
         if (this == o) return true;
         if (o == null || getClass() != o.getClass()) return false;
         WalletNode node = (WalletNode) o;
-        return derivationPath.equals(node.derivationPath);
+        return Objects.equals(wallet, node.wallet) && derivationPath.equals(node.derivationPath);
     }
 
     @Override
     public int hashCode() {
-        return derivationPath.hashCode();
+        return Objects.hash(wallet, derivationPath);
     }
 
     @Override
@@ -232,13 +288,13 @@ public class WalletNode extends Persistable implements Comparable<WalletNode> {
         }
     }
 
-    public WalletNode copy() {
+    public WalletNode copy(Wallet walletCopy) {
-        WalletNode copy = new WalletNode(derivationPath);
+        WalletNode copy = new WalletNode(walletCopy, derivationPath);
         copy.setId(getId());
         copy.setLabel(label);
 
         for(WalletNode child : getChildren()) {
-            copy.children.add(child.copy());
+            copy.children.add(child.copy(walletCopy));
         }
 
         for(BlockTransactionHashIndex txo : getTransactionOutputs()) {

src/main/java/com/sparrowwallet/drongo/wallet/WalletTransaction.java

@@ -79,7 +79,7 @@ public class WalletTransaction {
     }
 
     public Address getChangeAddress(WalletNode changeNode) {
-        return getWallet().getAddress(changeNode);
+        return changeNode.getAddress();
     }
 
     public long getFee() {

src/test/java/com/sparrowwallet/drongo/bip47/PaymentCodeTest.java

@@ -126,15 +126,15 @@ public class PaymentCodeTest {
         Assert.assertEquals("1JDdmqFLhpzcUwPeinhJbUPw4Co3aWLyzW", paymentCodeAlice.getNotificationAddress().toString());
 
         WalletNode sendNode0 = aliceBip47Wallet.getFreshNode(KeyPurpose.SEND);
-        Address address0 = aliceBip47Wallet.getAddress(sendNode0);
+        Address address0 = sendNode0.getAddress();
         Assert.assertEquals("141fi7TY3h936vRUKh1qfUZr8rSBuYbVBK", address0.toString());
 
         WalletNode sendNode1 = aliceBip47Wallet.getFreshNode(KeyPurpose.SEND, sendNode0);
-        Address address1 = aliceBip47Wallet.getAddress(sendNode1);
+        Address address1 = sendNode1.getAddress();
         Assert.assertEquals("12u3Uued2fuko2nY4SoSFGCoGLCBUGPkk6", address1.toString());
 
         WalletNode sendNode2 = aliceBip47Wallet.getFreshNode(KeyPurpose.SEND, sendNode1);
-        Address address2 = aliceBip47Wallet.getAddress(sendNode2);
+        Address address2 = sendNode2.getAddress();
         Assert.assertEquals("1FsBVhT5dQutGwaPePTYMe5qvYqqjxyftc", address2.toString());
 
         DeterministicSeed bobSeed = new DeterministicSeed("reward upper indicate eight swift arch injury crystal super wrestle already dentist", "", 0, DeterministicSeed.Type.BIP39);
@@ -149,15 +149,15 @@ public class PaymentCodeTest {
         Assert.assertEquals("1ChvUUvht2hUQufHBXF8NgLhW8SwE2ecGV", paymentCodeBob.getNotificationAddress().toString());
 
         WalletNode receiveNode0 = bobBip47Wallet.getFreshNode(KeyPurpose.RECEIVE);
-        Address receiveAddress0 = bobBip47Wallet.getAddress(receiveNode0);
+        Address receiveAddress0 = receiveNode0.getAddress();
         Assert.assertEquals("141fi7TY3h936vRUKh1qfUZr8rSBuYbVBK", receiveAddress0.toString());
 
         WalletNode receiveNode1 = bobBip47Wallet.getFreshNode(KeyPurpose.RECEIVE, receiveNode0);
-        Address receiveAddress1 = bobBip47Wallet.getAddress(receiveNode1);
+        Address receiveAddress1 = receiveNode1.getAddress();
         Assert.assertEquals("12u3Uued2fuko2nY4SoSFGCoGLCBUGPkk6", receiveAddress1.toString());
 
         WalletNode receiveNode2 = bobBip47Wallet.getFreshNode(KeyPurpose.RECEIVE, receiveNode1);
-        Address receiveAddress2 = bobBip47Wallet.getAddress(receiveNode2);
+        Address receiveAddress2 = receiveNode2.getAddress();
         Assert.assertEquals("1FsBVhT5dQutGwaPePTYMe5qvYqqjxyftc", receiveAddress2.toString());
 
         ECKey privKey0 = bobWallet.getKeystores().get(0).getKey(receiveNode0);

src/test/java/com/sparrowwallet/drongo/crypto/ECKeyTest.java

@@ -22,7 +22,7 @@ public class ECKeyTest {
         wallet.setDefaultPolicy(Policy.getPolicy(PolicyType.SINGLE, ScriptType.P2PKH, wallet.getKeystores(), 1));
 
         WalletNode firstReceive = wallet.getNode(KeyPurpose.RECEIVE).getChildren().iterator().next();
-        Address address = wallet.getAddress(firstReceive);
+        Address address = firstReceive.getAddress();
         Assert.assertEquals("14JmU9a7SzieZNEtBnsZo688rt3mGrw6hr", address.toString());
         ECKey privKey = keystore.getKey(firstReceive);
 

src/test/java/com/sparrowwallet/drongo/wallet/WalletTest.java

@@ -104,8 +104,10 @@ public class WalletTest {
         wallet.getKeystores().add(keystore);
         wallet.setDefaultPolicy(Policy.getPolicy(PolicyType.SINGLE, ScriptType.P2PKH, wallet.getKeystores(), 1));
 
-        Assert.assertEquals("12kTQjuWDp7Uu6PwY6CsS1KLTt3d1DBHZa", wallet.getAddress(new WalletNode(KeyPurpose.RECEIVE, 0)).toString());
+        WalletNode receive0 = new WalletNode(wallet, KeyPurpose.RECEIVE, 0);
-        Assert.assertEquals("1HbQwQCitHQxVtP39isXmUdHx7hQCZovrK", wallet.getAddress(new WalletNode(KeyPurpose.RECEIVE, 1)).toString());
+        Assert.assertEquals("12kTQjuWDp7Uu6PwY6CsS1KLTt3d1DBHZa", receive0.getAddress().toString());
+        WalletNode receive1 = new WalletNode(wallet, KeyPurpose.RECEIVE, 1);
+        Assert.assertEquals("1HbQwQCitHQxVtP39isXmUdHx7hQCZovrK", receive1.getAddress().toString());
     }
 
     @Test
@@ -119,8 +121,10 @@ public class WalletTest {
         wallet.getKeystores().add(keystore);
         wallet.setDefaultPolicy(Policy.getPolicy(PolicyType.SINGLE, ScriptType.P2SH_P2WPKH, wallet.getKeystores(), 1));
 
-        Assert.assertEquals("3NZLE4TntsjtcZ5MbrfxwtYo9meBVybVQj", wallet.getAddress(new WalletNode(KeyPurpose.RECEIVE, 0)).toString());
+        WalletNode receive0 = new WalletNode(wallet, KeyPurpose.RECEIVE, 0);
-        Assert.assertEquals("32YBBuRsp8XTeLx4T6BmD2L4nANGaNDkSg", wallet.getAddress(new WalletNode(KeyPurpose.RECEIVE, 1)).toString());
+        Assert.assertEquals("3NZLE4TntsjtcZ5MbrfxwtYo9meBVybVQj", receive0.getAddress().toString());
+        WalletNode receive1 = new WalletNode(wallet, KeyPurpose.RECEIVE, 1);
+        Assert.assertEquals("32YBBuRsp8XTeLx4T6BmD2L4nANGaNDkSg", receive1.getAddress().toString());
     }
 
     @Test
@@ -134,8 +138,10 @@ public class WalletTest {
         wallet.getKeystores().add(keystore);
         wallet.setDefaultPolicy(Policy.getPolicy(PolicyType.SINGLE, ScriptType.P2WPKH, wallet.getKeystores(), 1));
 
-        Assert.assertEquals("bc1quvxdut936uswuxwxrk6nvjmgwxh463r0fjwn55", wallet.getAddress(new WalletNode(KeyPurpose.RECEIVE, 0)).toString());
+        WalletNode receive0 = new WalletNode(wallet, KeyPurpose.RECEIVE, 0);
-        Assert.assertEquals("bc1q95j2862dz7mqpraw6qdjc70gumyu5z7adgq9x9", wallet.getAddress(new WalletNode(KeyPurpose.RECEIVE, 1)).toString());
+        Assert.assertEquals("bc1quvxdut936uswuxwxrk6nvjmgwxh463r0fjwn55", receive0.getAddress().toString());
+        WalletNode receive1 = new WalletNode(wallet, KeyPurpose.RECEIVE, 1);
+        Assert.assertEquals("bc1q95j2862dz7mqpraw6qdjc70gumyu5z7adgq9x9", receive1.getAddress().toString());
     }
 
     @Test
@@ -159,8 +165,10 @@ public class WalletTest {
         wallet.getKeystores().add(keystore2);
         wallet.setDefaultPolicy(Policy.getPolicy(PolicyType.MULTI, ScriptType.P2SH, wallet.getKeystores(), 2));
 
-        Assert.assertEquals("38kq6yz4VcYymTExQPY3gppbz38mtPLveK", wallet.getAddress(new WalletNode(KeyPurpose.RECEIVE, 0)).toString());
+        WalletNode receive0 = new WalletNode(wallet, KeyPurpose.RECEIVE, 0);
-        Assert.assertEquals("3EdKaNsnjBTBggWcSMRyVju6GbHWy68mAH", wallet.getAddress(new WalletNode(KeyPurpose.CHANGE, 1)).toString());
+        Assert.assertEquals("38kq6yz4VcYymTExQPY3gppbz38mtPLveK", receive0.getAddress().toString());
+        WalletNode receive1 = new WalletNode(wallet, KeyPurpose.CHANGE, 1);
+        Assert.assertEquals("3EdKaNsnjBTBggWcSMRyVju6GbHWy68mAH", receive1.getAddress().toString());
     }
 
     @Test
@@ -184,8 +192,10 @@ public class WalletTest {
         wallet.getKeystores().add(keystore2);
         wallet.setDefaultPolicy(Policy.getPolicy(PolicyType.MULTI, ScriptType.P2SH_P2WSH, wallet.getKeystores(), 2));
 
-        Assert.assertEquals("3Mw8xqAHh8g3eBvh7q1UEUmoexqdXDK9Tf", wallet.getAddress(new WalletNode(KeyPurpose.RECEIVE, 0)).toString());
+        WalletNode receive0 = new WalletNode(wallet, KeyPurpose.RECEIVE, 0);
-        Assert.assertEquals("35dFo1ivJ8jyHpyf42MWvnYf5LBU8Siren", wallet.getAddress(new WalletNode(KeyPurpose.CHANGE, 1)).toString());
+        Assert.assertEquals("3Mw8xqAHh8g3eBvh7q1UEUmoexqdXDK9Tf", receive0.getAddress().toString());
+        WalletNode receive1 = new WalletNode(wallet, KeyPurpose.CHANGE, 1);
+        Assert.assertEquals("35dFo1ivJ8jyHpyf42MWvnYf5LBU8Siren", receive1.getAddress().toString());
     }
 
     @Test
@@ -209,8 +219,10 @@ public class WalletTest {
         wallet.getKeystores().add(keystore2);
         wallet.setDefaultPolicy(Policy.getPolicy(PolicyType.MULTI, ScriptType.P2WSH, wallet.getKeystores(), 2));
 
-        Assert.assertEquals("bc1q20e4vm656h5lvmngz9ztz6hjzftvh39yzngqhuqzk8qzj7tqnzaqgclrwc", wallet.getAddress(new WalletNode(KeyPurpose.RECEIVE, 0)).toString());
+        WalletNode receive0 = new WalletNode(wallet, KeyPurpose.RECEIVE, 0);
-        Assert.assertEquals("bc1q2epdx7dplwaas2jucfrzmxm8350rqh68hs6vqreysku80ye44mfqla85f2", wallet.getAddress(new WalletNode(KeyPurpose.CHANGE, 1)).toString());
+        Assert.assertEquals("bc1q20e4vm656h5lvmngz9ztz6hjzftvh39yzngqhuqzk8qzj7tqnzaqgclrwc", receive0.getAddress().toString());
+        WalletNode receive1 = new WalletNode(wallet, KeyPurpose.CHANGE, 1);
+        Assert.assertEquals("bc1q2epdx7dplwaas2jucfrzmxm8350rqh68hs6vqreysku80ye44mfqla85f2", receive1.getAddress().toString());
     }
 
     @Test
@@ -227,6 +239,7 @@ public class WalletTest {
         List<ChildNumber> derivation = List.of(keystore.getExtendedPublicKey().getKeyChildNumber(), new ChildNumber(0));
         Assert.assertEquals("027ecc656f4b91b92881b6f07cf876cd2e42b20df7acc4df54fc3315fbb2d13e1c", Utils.bytesToHex(extendedKey.getKey(derivation).getPubKey()));
 
-        Assert.assertEquals("bc1qarzeu6ncapyvjzdeayjq8vnzp6uvcn4eaeuuqq", wallet.getAddress(new WalletNode(KeyPurpose.RECEIVE, 0)).toString());
+        WalletNode receive0 = new WalletNode(wallet, KeyPurpose.RECEIVE, 0);
+        Assert.assertEquals("bc1qarzeu6ncapyvjzdeayjq8vnzp6uvcn4eaeuuqq", receive0.getAddress().toString());
     }
 }