Reverting wrong renaming

src/main/java/com/luminiasoft/bitshares/Authority.java

@@ -2,6 +2,7 @@ package com.luminiasoft.bitshares;
 
 import com.google.gson.JsonElement;
 import com.luminiasoft.bitshares.errors.MalformedAddressException;
+import com.luminiasoft.bitshares.interfaces.ByteSerializable;
 import com.luminiasoft.bitshares.interfaces.JsonSerializable;
 
 import java.util.HashMap;

src/main/java/com/luminiasoft/bitshares/Test.java

@@ -35,10 +35,10 @@ public class Test {
     public static final String OPENLEDGER_WITNESS_URL = "wss://bitshares.openledger.info/ws";
 //    public static final String WITNESS_URL = "wss://fr.blockpay.ch:8089";
 
-    private TransferOperation transferOperation;
+    private Transaction transaction;
 
-    public TransferOperation getTransferOperation() {
+    public Transaction getTransaction() {
-        return transferOperation;
+        return transaction;
     }
 
     private WitnessResponseListener mListener = new WitnessResponseListener() {
@@ -109,27 +109,27 @@ public class Test {
     };
 
     public ECKey.ECDSASignature testSigning() {
-        byte[] serializedTransaction = this.transferOperation.toBytes();
+        byte[] serializedTransaction = this.transaction.toBytes();
         Sha256Hash hash = Sha256Hash.wrap(Sha256Hash.hash(serializedTransaction));
         byte[] bytesDigest = hash.getBytes();
-        ECKey sk = transferOperation.getPrivateKey();
+        ECKey sk = transaction.getPrivateKey();
         ECKey.ECDSASignature signature = sk.sign(hash);
         return signature;
     }
 
     public String testSigningMessage() {
-        byte[] serializedTransaction = this.transferOperation.toBytes();
+        byte[] serializedTransaction = this.transaction.toBytes();
         Sha256Hash hash = Sha256Hash.wrap(Sha256Hash.hash(serializedTransaction));
-        ECKey sk = transferOperation.getPrivateKey();
+        ECKey sk = transaction.getPrivateKey();
         return sk.signMessage(hash.toString());
     }
 
     public byte[] signMessage() {
-        byte[] serializedTransaction = this.transferOperation.toBytes();
+        byte[] serializedTransaction = this.transaction.toBytes();
         Sha256Hash hash = Sha256Hash.wrap(Sha256Hash.hash(serializedTransaction));
         System.out.println(">> digest <<");
         System.out.println(Util.bytesToHex(hash.getBytes()));
-        ECKey sk = transferOperation.getPrivateKey();
+        ECKey sk = transaction.getPrivateKey();
         System.out.println("Private key bytes");
         System.out.println(Util.bytesToHex(sk.getPrivKeyBytes()));
         boolean isCanonical = false;
@@ -183,10 +183,10 @@ public class Test {
         UserAccount to = new UserAccount("1.2.129848");
         AssetAmount amount = new AssetAmount(UnsignedLong.valueOf(100), new Asset("1.3.120"));
         AssetAmount fee = new AssetAmount(UnsignedLong.valueOf(264174), new Asset("1.3.0"));
-        operations.add(new Transfer(from, to, amount, fee));
+        operations.add(new TransferOperation(from, to, amount, fee));
-        this.transferOperation = new TransferOperation(Main.WIF, blockData, operations);
+        this.transaction = new Transaction(Main.WIF, blockData, operations);
-        byte[] serializedTransaction = this.transferOperation.toBytes();
+        byte[] serializedTransaction = this.transaction.toBytes();
-        System.out.println("Serialized transferOperation");
+        System.out.println("Serialized transaction");
         System.out.println(Util.bytesToHex(serializedTransaction));
     }
 
@@ -335,7 +335,7 @@ public class Test {
 
     public void testTransactionSerialization() {
         try {
-            TransferOperation transferOperation = new TransferTransactionBuilder()
+            Transaction transaction = new TransferTransactionBuilder()
                     .setSource(new UserAccount("1.2.138632"))
                     .setDestination(new UserAccount("1.2.129848"))
                     .setAmount(new AssetAmount(UnsignedLong.valueOf(100), new Asset("1.3.120")))
@@ -345,9 +345,9 @@ public class Test {
                     .build();
 
             ArrayList<Serializable> transactionList = new ArrayList<>();
-            transactionList.add(transferOperation);
+            transactionList.add(transaction);
 
-            byte[] signature = transferOperation.getGrapheneSignature();
+            byte[] signature = transaction.getGrapheneSignature();
             System.out.println(Util.bytesToHex(signature));
             ApiCall call = new ApiCall(4, "call", "broadcast_transaction", transactionList, "2.0", 1);
             String jsonCall = call.toJsonString();
@@ -420,7 +420,7 @@ public class Test {
         };
 
         try {
-            TransferOperation transferOperation = new TransferTransactionBuilder()
+            Transaction transaction = new TransferTransactionBuilder()
                     .setSource(new UserAccount("1.2.138632"))
                     .setDestination(new UserAccount("1.2.129848"))
                     .setAmount(new AssetAmount(UnsignedLong.valueOf(100), new Asset("1.3.120")))
@@ -430,9 +430,9 @@ public class Test {
                     .build();
 
             ArrayList<Serializable> transactionList = new ArrayList<>();
-            transactionList.add(transferOperation);
+            transactionList.add(transaction);
 
-            transactionList.add(transferOperation);
+            transactionList.add(transaction);
 
             SSLContext context = null;
             context = NaiveSSLContext.getInstance("TLS");
@@ -443,7 +443,7 @@ public class Test {
 
             WebSocket mWebSocket = factory.createSocket(OPENLEDGER_WITNESS_URL);
 
-            mWebSocket.addListener(new TransactionBroadcastSequence(transferOperation, listener));
+            mWebSocket.addListener(new TransactionBroadcastSequence(transaction, listener));
             mWebSocket.connect();
 
         } catch (MalformedTransactionException e) {
@@ -514,7 +514,7 @@ public class Test {
         UserAccount to = new UserAccount("1.2.129848");
         AssetAmount amount = new AssetAmount(UnsignedLong.valueOf(100), new Asset("1.3.120"));
         AssetAmount fee = new AssetAmount(UnsignedLong.valueOf(264174), new Asset("1.3.0"));
-        Transfer transfer = new Transfer(from, to, amount, fee);
+        TransferOperation transfer = new TransferOperation(from, to, amount, fee);
         ArrayList<BaseOperation> operations = new ArrayList<>();
         operations.add(transfer);
 

src/main/java/com/luminiasoft/bitshares/Transaction.java

@@ -0,0 +1,211 @@
+package com.luminiasoft.bitshares;
+
+import com.google.common.primitives.Bytes;
+import com.google.gson.GsonBuilder;
+import com.google.gson.JsonArray;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonSerializationContext;
+import com.google.gson.JsonSerializer;
+import com.luminiasoft.bitshares.interfaces.ByteSerializable;
+import com.luminiasoft.bitshares.interfaces.JsonSerializable;
+
+import org.bitcoinj.core.DumpedPrivateKey;
+import org.bitcoinj.core.ECKey;
+import org.bitcoinj.core.Sha256Hash;
+import org.bitcoinj.core.Utils;
+
+import java.lang.reflect.Type;
+import java.text.SimpleDateFormat;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.List;
+import java.util.TimeZone;
+
+/**
+ * Class used to represent a generic graphene transaction.
+ */
+public class Transaction implements ByteSerializable, JsonSerializable {
+    private final String TAG = this.getClass().getName();
+
+    public static final String KEY_EXPIRATION = "expiration";
+    public static final String KEY_SIGNATURES = "signatures";
+    public static final String KEY_OPERATIONS = "operations";
+    public static final String KEY_EXTENSIONS = "extensions";
+    public static final String KEY_REF_BLOCK_NUM = "ref_block_num";
+    public static final String KEY_REF_BLOCK_PREFIX = "ref_block_prefix";
+
+    private ECKey privateKey;
+    private BlockData blockData;
+    private List<BaseOperation> operations;
+    private List<Extension> extensions;
+
+    /**
+     * Transaction constructor.
+     * @param wif: The user's private key in the base58 format.
+     * @param block_data: Block data containing important information used to sign a transaction.
+     * @param operation_list: List of operations to include in the transaction.
+     */
+    public Transaction(String wif, BlockData block_data, List<BaseOperation> operation_list){
+        this.privateKey = DumpedPrivateKey.fromBase58(null, wif).getKey();
+        this.blockData = block_data;
+        this.operations = operation_list;
+        this.extensions = new ArrayList<Extension>();
+    }
+
+    /**
+     * Transaction constructor.
+     * @param privateKey : Instance of a ECKey containing the private key that will be used to sign this transaction.
+     * @param blockData : Block data containing important information used to sign a transaction.
+     * @param operationList : List of operations to include in the transaction.
+     */
+    public Transaction(ECKey privateKey, BlockData blockData, List<BaseOperation> operationList){
+        this.privateKey = privateKey;
+        this.blockData = blockData;
+        this.operations = operationList;
+        this.extensions = new ArrayList<Extension>();
+    }
+
+    public ECKey getPrivateKey(){
+        return this.privateKey;
+    }
+
+    public List<BaseOperation> getOperations(){ return this.operations; }
+
+    /**
+     * Obtains a signature of this transaction. Please note that due to the current reliance on
+     * bitcoinj to generate the signatures, and due to the fact that it uses deterministic
+     * ecdsa signatures, we are slightly modifying the expiration time of the transaction while
+     * we look for a signature that will be accepted by the graphene network.
+     *
+     * This should then be called before any other serialization method.
+     * @return: A valid signature of the current transaction.
+     */
+    public byte[] getGrapheneSignature(){
+        boolean isGrapheneCanonical = false;
+        byte[] sigData = null;
+
+        while(!isGrapheneCanonical) {
+            byte[] serializedTransaction = this.toBytes();
+            Sha256Hash hash = Sha256Hash.wrap(Sha256Hash.hash(serializedTransaction));
+            int recId = -1;
+            ECKey.ECDSASignature sig = privateKey.sign(hash);
+
+            // Now we have to work backwards to figure out the recId needed to recover the signature.
+            for (int i = 0; i < 4; i++) {
+                ECKey k = ECKey.recoverFromSignature(i, sig, hash, privateKey.isCompressed());
+                if (k != null && k.getPubKeyPoint().equals(privateKey.getPubKeyPoint())) {
+                    recId = i;
+                    break;
+                }
+            }
+
+            sigData = new byte[65];  // 1 header + 32 bytes for R + 32 bytes for S
+            int headerByte = recId + 27 + (privateKey.isCompressed() ? 4 : 0);
+            sigData[0] = (byte) headerByte;
+            System.arraycopy(Utils.bigIntegerToBytes(sig.r, 32), 0, sigData, 1, 32);
+            System.arraycopy(Utils.bigIntegerToBytes(sig.s, 32), 0, sigData, 33, 32);
+
+            // Further "canonicality" tests
+            if(((sigData[0] & 0x80) != 0) || (sigData[0] == 0) ||
+                    ((sigData[1] & 0x80) != 0) || ((sigData[32] & 0x80) != 0) ||
+                    (sigData[32] == 0) || ((sigData[33] & 0x80)  != 0)){
+                this.blockData.setRelativeExpiration(this.blockData.getRelativeExpiration() + 1);
+            }else{
+                isGrapheneCanonical = true;
+            }
+        }
+        return sigData;
+    }
+
+    /**
+     * Method that creates a serialized byte array with compact information about this transaction
+     * that is needed for the creation of a signature.
+     * @return: byte array with serialized information about this transaction.
+     */
+    public byte[] toBytes(){
+        // Creating a List of Bytes and adding the first bytes from the chain apiId
+        List<Byte> byteArray = new ArrayList<Byte>();
+        byteArray.addAll(Bytes.asList(Util.hexToBytes(Chains.BITSHARES.CHAIN_ID)));
+
+        // Adding the block data
+        byteArray.addAll(Bytes.asList(this.blockData.toBytes()));
+
+        // Adding the number of operations
+        byteArray.add((byte) this.operations.size());
+
+        // Adding all the operations
+        for(BaseOperation operation : operations){
+            byteArray.add(operation.getId());
+            byteArray.addAll(Bytes.asList(operation.toBytes()));
+        }
+
+        //Adding the number of extensions
+        byteArray.add((byte) this.extensions.size());
+
+        for(Extension extension : extensions){
+            //TODO: Implement the extension serialization
+        }
+        // Adding a last zero byte to match the result obtained by the python-graphenelib code
+        // I'm not exactly sure what's the meaning of this last zero byte, but for now I'll just
+        // leave it here and work on signing the transaction.
+        //TODO: Investigate the origin and meaning of this last byte.
+        byteArray.add((byte) 0 );
+
+        return Bytes.toArray(byteArray);
+    }
+
+    @Override
+    public String toJsonString() {
+        GsonBuilder gsonBuilder = new GsonBuilder();
+        gsonBuilder.registerTypeAdapter(Transaction.class, new TransactionSerializer());
+        return gsonBuilder.create().toJson(this);
+    }
+
+    @Override
+    public JsonObject toJsonObject() {
+        JsonObject obj = new JsonObject();
+
+        // Getting the signature before anything else,
+        // since this might change the transaction expiration data slightly
+        byte[] signature = getGrapheneSignature();
+
+        // Formatting expiration time
+        Date expirationTime = new Date(blockData.getRelativeExpiration() * 1000);
+        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
+        dateFormat.setTimeZone(TimeZone.getTimeZone("GMT"));
+
+        // Adding expiration
+        obj.addProperty(KEY_EXPIRATION, dateFormat.format(expirationTime));
+
+        // Adding signatures
+        JsonArray signatureArray = new JsonArray();
+        signatureArray.add(Util.bytesToHex(signature));
+        obj.add(KEY_SIGNATURES, signatureArray);
+
+        JsonArray operationsArray = new JsonArray();
+        for(BaseOperation operation : operations){
+            operationsArray.add(operation.toJsonObject());
+        }
+        // Adding operations
+        obj.add(KEY_OPERATIONS, operationsArray);
+
+        // Adding extensions
+        obj.add(KEY_EXTENSIONS, new JsonArray());
+
+        // Adding block data
+        obj.addProperty(KEY_REF_BLOCK_NUM, blockData.getRefBlockNum());
+        obj.addProperty(KEY_REF_BLOCK_PREFIX, blockData.getRefBlockPrefix());
+
+        return obj;
+
+    }
+
+    class TransactionSerializer implements JsonSerializer<Transaction> {
+
+        @Override
+        public JsonElement serialize(Transaction transaction, Type type, JsonSerializationContext jsonSerializationContext) {
+            return transaction.toJsonObject();
+        }
+    }
+}

src/main/java/com/luminiasoft/bitshares/TransactionBuilder.java

@@ -11,5 +11,5 @@ public abstract class TransactionBuilder {
     protected ECKey privateKey;
     protected BlockData blockData;
 
-    public abstract TransferOperation build() throws MalformedTransactionException;
+    public abstract Transaction build() throws MalformedTransactionException;
 }

src/main/java/com/luminiasoft/bitshares/Transfer.java

@@ -1,168 +0,0 @@
-package com.luminiasoft.bitshares;
-
-import com.google.common.primitives.Bytes;
-import com.google.common.primitives.UnsignedLong;
-import com.google.gson.*;
-
-import java.lang.reflect.Type;
-
-/**
- * Class used to encapsulate the Transfer operation related functionalities.
- * TODO: Add extensions support
- */
-public class Transfer extends BaseOperation {
-    public static final String KEY_FEE = "fee";
-    public static final String KEY_AMOUNT = "amount";
-    public static final String KEY_EXTENSIONS = "extensions";
-    public static final String KEY_FROM = "from";
-    public static final String KEY_TO = "to";
-
-    private AssetAmount fee;
-    private AssetAmount amount;
-    private UserAccount from;
-    private UserAccount to;
-    private Memo memo;
-    private String[] extensions;
-
-    public Transfer(UserAccount from, UserAccount to, AssetAmount transferAmount, AssetAmount fee){
-        super(OperationType.transfer_operation);
-        this.from = from;
-        this.to = to;
-        this.amount = transferAmount;
-        this.fee = fee;
-        this.memo = new Memo();
-    }
-
-    public Transfer(UserAccount from, UserAccount to, AssetAmount transferAmount){
-        super(OperationType.transfer_operation);
-        this.from = from;
-        this.to = to;
-        this.amount = transferAmount;
-        this.memo = new Memo();
-    }
-
-    public void setFee(AssetAmount newFee){
-        this.fee = newFee;
-    }
-
-    @Override
-    public byte getId() {
-        return (byte) this.type.ordinal();
-    }
-
-    public UserAccount getFrom(){
-        return this.from;
-    }
-
-    public UserAccount getTo(){
-        return this.to;
-    }
-
-    public AssetAmount getAmount(){
-        return this.amount;
-    }
-
-    public AssetAmount getFee(){
-        return this.fee;
-    }
-
-    @Override
-    public byte[] toBytes() {
-        byte[] feeBytes = fee.toBytes();
-        byte[] fromBytes = from.toBytes();
-        byte[] toBytes = to.toBytes();
-        byte[] amountBytes = amount.toBytes();
-        byte[] memoBytes = memo.toBytes();
-        return Bytes.concat(feeBytes, fromBytes, toBytes, amountBytes, memoBytes);
-    }
-
-    @Override
-    public String toJsonString() {
-        GsonBuilder gsonBuilder = new GsonBuilder();
-        gsonBuilder.registerTypeAdapter(Transfer.class, new TransferSerializer());
-        return gsonBuilder.create().toJson(this);
-    }
-
-    @Override
-    public JsonElement toJsonObject() {
-        JsonArray array = new JsonArray();
-        array.add(this.getId());
-        JsonObject jsonObject = new JsonObject();
-        jsonObject.add(KEY_FEE, fee.toJsonObject());
-        jsonObject.add(KEY_AMOUNT, amount.toJsonObject());
-        jsonObject.add(KEY_EXTENSIONS, new JsonArray());
-        jsonObject.addProperty(KEY_FROM, from.toJsonString());
-        jsonObject.addProperty(KEY_TO, to.toJsonString());
-        array.add(jsonObject);
-        return array;
-    }
-
-    public static class TransferSerializer implements JsonSerializer<Transfer> {
-
-        @Override
-        public JsonElement serialize(Transfer transfer, Type type, JsonSerializationContext jsonSerializationContext) {
-            JsonArray arrayRep = new JsonArray();
-            arrayRep.add(transfer.getId());
-            arrayRep.add(transfer.toJsonObject());
-            return arrayRep;
-        }
-    }
-
-    /**
-     * This deserializer will work on any transfer operation serialized in the 'array form' used a lot in
-     * the Graphene Blockchain API.
-     *
-     * An example of this serialized form is the following:
-     *
-     *    [
-     *       0,
-     *       {
-     *           "fee": {
-     *               "amount": 264174,
-     *               "asset_id": "1.3.0"
-     *           },
-     *           "from": "1.2.138632",
-     *           "to": "1.2.129848",
-     *           "amount": {
-     *               "amount": 100,
-     *               "asset_id": "1.3.0"
-     *           },
-     *           "extensions": []
-     *       }
-     *    ]
-     *
-     * It will convert this data into a nice Transfer object.
-     */
-    public static class TransferDeserializer implements JsonDeserializer<Transfer> {
-
-        @Override
-        public Transfer deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException {
-            if(json.isJsonArray()){
-                // This block is used just to check if we are in the first step of the deserialization
-                // when we are dealing with an array.
-                JsonArray serializedTransfer = json.getAsJsonArray();
-                if(serializedTransfer.get(0).getAsInt() != OperationType.transfer_operation.ordinal()){
-                    // If the operation type does not correspond to a transfer operation, we return null
-                    return null;
-                }else{
-                    // Calling itself recursively, this is only done once, so there will be no problems.
-                    return context.deserialize(serializedTransfer.get(1), Transfer.class);
-                }
-            }else{
-                // This block is called in the second recursion and takes care of deserializing the
-                // transfer data itself.
-                JsonObject jsonObject = json.getAsJsonObject();
-
-                // Deserializing AssetAmount objects
-                AssetAmount amount = context.deserialize(jsonObject.get("amount"), AssetAmount.class);
-                AssetAmount fee = context.deserialize(jsonObject.get("fee"), AssetAmount.class);
-
-                // Deserializing UserAccount objects
-                UserAccount from = new UserAccount(jsonObject.get("from").getAsString());
-                UserAccount to = new UserAccount(jsonObject.get("to").getAsString());
-                Transfer transfer = new Transfer(from, to, amount, fee);
-                return transfer;
-            }
-        }
-    }
-}

src/main/java/com/luminiasoft/bitshares/TransferOperation.java

@@ -1,218 +1,167 @@
 package com.luminiasoft.bitshares;
 
 import com.google.common.primitives.Bytes;
-import com.google.gson.GsonBuilder;
+import com.google.gson.*;
-import com.google.gson.JsonArray;
-import com.google.gson.JsonElement;
-import com.google.gson.JsonObject;
-import com.google.gson.JsonSerializationContext;
-import com.google.gson.JsonSerializer;
-import com.luminiasoft.bitshares.interfaces.ByteSerializable;
-import com.luminiasoft.bitshares.interfaces.JsonSerializable;
-
-import org.bitcoinj.core.DumpedPrivateKey;
-import org.bitcoinj.core.ECKey;
-import org.bitcoinj.core.Sha256Hash;
-import org.bitcoinj.core.Utils;
 
 import java.lang.reflect.Type;
-import java.text.SimpleDateFormat;
-import java.util.ArrayList;
-import java.util.Date;
-import java.util.List;
-import java.util.TimeZone;
 
 /**
- * Class used to represent a generic graphene transaction.
+ * Class used to encapsulate the TransferOperation operation related functionalities.
+ * TODO: Add extensions support
  */
-public class TransferOperation extends BaseOperation implements ByteSerializable, JsonSerializable {
+public class TransferOperation extends BaseOperation {
-    private final String TAG = this.getClass().getName();
+    public static final String KEY_FEE = "fee";
-
+    public static final String KEY_AMOUNT = "amount";
-    public static final String KEY_EXPIRATION = "expiration";
-    public static final String KEY_SIGNATURES = "signatures";
-    public static final String KEY_OPERATIONS = "operations";
     public static final String KEY_EXTENSIONS = "extensions";
-    public static final String KEY_REF_BLOCK_NUM = "ref_block_num";
+    public static final String KEY_FROM = "from";
-    public static final String KEY_REF_BLOCK_PREFIX = "ref_block_prefix";
+    public static final String KEY_TO = "to";
 
-    private ECKey privateKey;
+    private AssetAmount fee;
-    private BlockData blockData;
+    private AssetAmount amount;
-    private List<BaseOperation> operations;
+    private UserAccount from;
-    private List<Extension> extensions;
+    private UserAccount to;
+    private Memo memo;
+    private String[] extensions;
 
-    /**
+    public TransferOperation(UserAccount from, UserAccount to, AssetAmount transferAmount, AssetAmount fee){
-     * TransferOperation constructor.
-     * @param wif: The user's private key in the base58 format.
-     * @param block_data: Block data containing important information used to sign a transaction.
-     * @param operation_list: List of operations to include in the transaction.
-     */
-    public TransferOperation(String wif, BlockData block_data, List<BaseOperation> operation_list){
         super(OperationType.transfer_operation);
-        this.privateKey = DumpedPrivateKey.fromBase58(null, wif).getKey();
+        this.from = from;
-        this.blockData = block_data;
+        this.to = to;
-        this.operations = operation_list;
+        this.amount = transferAmount;
-        this.extensions = new ArrayList<Extension>();
+        this.fee = fee;
+        this.memo = new Memo();
     }
 
-    /**
+    public TransferOperation(UserAccount from, UserAccount to, AssetAmount transferAmount){
-     * TransferOperation constructor.
-     * @param privateKey : Instance of a ECKey containing the private key that will be used to sign this transaction.
-     * @param blockData : Block data containing important information used to sign a transaction.
-     * @param operationList : List of operations to include in the transaction.
-     */
-    public TransferOperation(ECKey privateKey, BlockData blockData, List<BaseOperation> operationList){
         super(OperationType.transfer_operation);
-        this.privateKey = privateKey;
+        this.from = from;
-        this.blockData = blockData;
+        this.to = to;
-        this.operations = operationList;
+        this.amount = transferAmount;
-        this.extensions = new ArrayList<Extension>();
+        this.memo = new Memo();
     }
 
-    public ECKey getPrivateKey(){
+    public void setFee(AssetAmount newFee){
-        return this.privateKey;
+        this.fee = newFee;
-    }
-
-    public List<BaseOperation> getOperations(){ return this.operations; }
-
-    /**
-     * Obtains a signature of this transaction. Please note that due to the current reliance on
-     * bitcoinj to generate the signatures, and due to the fact that it uses deterministic
-     * ecdsa signatures, we are slightly modifying the expiration time of the transaction while
-     * we look for a signature that will be accepted by the graphene network.
-     *
-     * This should then be called before any other serialization method.
-     * @return: A valid signature of the current transaction.
-     */
-    public byte[] getGrapheneSignature(){
-        boolean isGrapheneCanonical = false;
-        byte[] sigData = null;
-
-        while(!isGrapheneCanonical) {
-            byte[] serializedTransaction = this.toBytes();
-            Sha256Hash hash = Sha256Hash.wrap(Sha256Hash.hash(serializedTransaction));
-            int recId = -1;
-            ECKey.ECDSASignature sig = privateKey.sign(hash);
-
-            // Now we have to work backwards to figure out the recId needed to recover the signature.
-            for (int i = 0; i < 4; i++) {
-                ECKey k = ECKey.recoverFromSignature(i, sig, hash, privateKey.isCompressed());
-                if (k != null && k.getPubKeyPoint().equals(privateKey.getPubKeyPoint())) {
-                    recId = i;
-                    break;
-                }
-            }
-
-            sigData = new byte[65];  // 1 header + 32 bytes for R + 32 bytes for S
-            int headerByte = recId + 27 + (privateKey.isCompressed() ? 4 : 0);
-            sigData[0] = (byte) headerByte;
-            System.arraycopy(Utils.bigIntegerToBytes(sig.r, 32), 0, sigData, 1, 32);
-            System.arraycopy(Utils.bigIntegerToBytes(sig.s, 32), 0, sigData, 33, 32);
-
-            // Further "canonicality" tests
-            if(((sigData[0] & 0x80) != 0) || (sigData[0] == 0) ||
-                    ((sigData[1] & 0x80) != 0) || ((sigData[32] & 0x80) != 0) ||
-                    (sigData[32] == 0) || ((sigData[33] & 0x80)  != 0)){
-                this.blockData.setRelativeExpiration(this.blockData.getRelativeExpiration() + 1);
-            }else{
-                isGrapheneCanonical = true;
-            }
-        }
-        return sigData;
     }
 
     @Override
     public byte getId() {
-        return 0;
+        return (byte) this.type.ordinal();
     }
 
-    /**
+    public UserAccount getFrom(){
-     * Method that creates a serialized byte array with compact information about this transaction
+        return this.from;
-     * that is needed for the creation of a signature.
+    }
-     * @return: byte array with serialized information about this transaction.
+
-     */
+    public UserAccount getTo(){
+        return this.to;
+    }
+
+    public AssetAmount getAmount(){
+        return this.amount;
+    }
+
+    public AssetAmount getFee(){
+        return this.fee;
+    }
+
+    @Override
     public byte[] toBytes() {
-        // Creating a List of Bytes and adding the first bytes from the chain apiId
+        byte[] feeBytes = fee.toBytes();
-        List<Byte> byteArray = new ArrayList<Byte>();
+        byte[] fromBytes = from.toBytes();
-        byteArray.addAll(Bytes.asList(Util.hexToBytes(Chains.BITSHARES.CHAIN_ID)));
+        byte[] toBytes = to.toBytes();
-
+        byte[] amountBytes = amount.toBytes();
-        // Adding the block data
+        byte[] memoBytes = memo.toBytes();
-        byteArray.addAll(Bytes.asList(this.blockData.toBytes()));
+        return Bytes.concat(feeBytes, fromBytes, toBytes, amountBytes, memoBytes);
-
-        // Adding the number of operations
-        byteArray.add((byte) this.operations.size());
-
-        // Adding all the operations
-        for(BaseOperation operation : operations){
-            byteArray.add(operation.getId());
-            byteArray.addAll(Bytes.asList(operation.toBytes()));
-        }
-
-        //Adding the number of extensions
-        byteArray.add((byte) this.extensions.size());
-
-        for(Extension extension : extensions){
-            //TODO: Implement the extension serialization
-        }
-        // Adding a last zero byte to match the result obtained by the python-graphenelib code
-        // I'm not exactly sure what's the meaning of this last zero byte, but for now I'll just
-        // leave it here and work on signing the transaction.
-        //TODO: Investigate the origin and meaning of this last byte.
-        byteArray.add((byte) 0 );
-
-        return Bytes.toArray(byteArray);
     }
 
     @Override
     public String toJsonString() {
         GsonBuilder gsonBuilder = new GsonBuilder();
-        gsonBuilder.registerTypeAdapter(TransferOperation.class, new TransactionSerializer());
+        gsonBuilder.registerTypeAdapter(TransferOperation.class, new TransferSerializer());
         return gsonBuilder.create().toJson(this);
     }
 
     @Override
-    public JsonObject toJsonObject() {
+    public JsonElement toJsonObject() {
-        JsonObject obj = new JsonObject();
+        JsonArray array = new JsonArray();
-
+        array.add(this.getId());
-        // Getting the signature before anything else,
+        JsonObject jsonObject = new JsonObject();
-        // since this might change the transaction expiration data slightly
+        jsonObject.add(KEY_FEE, fee.toJsonObject());
-        byte[] signature = getGrapheneSignature();
+        jsonObject.add(KEY_AMOUNT, amount.toJsonObject());
-
+        jsonObject.add(KEY_EXTENSIONS, new JsonArray());
-        // Formatting expiration time
+        jsonObject.addProperty(KEY_FROM, from.toJsonString());
-        Date expirationTime = new Date(blockData.getRelativeExpiration() * 1000);
+        jsonObject.addProperty(KEY_TO, to.toJsonString());
-        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
+        array.add(jsonObject);
-        dateFormat.setTimeZone(TimeZone.getTimeZone("GMT"));
+        return array;
-
-        // Adding expiration
-        obj.addProperty(KEY_EXPIRATION, dateFormat.format(expirationTime));
-
-        // Adding signatures
-        JsonArray signatureArray = new JsonArray();
-        signatureArray.add(Util.bytesToHex(signature));
-        obj.add(KEY_SIGNATURES, signatureArray);
-
-        JsonArray operationsArray = new JsonArray();
-        for(BaseOperation operation : operations){
-            operationsArray.add(operation.toJsonObject());
-        }
-        // Adding operations
-        obj.add(KEY_OPERATIONS, operationsArray);
-
-        // Adding extensions
-        obj.add(KEY_EXTENSIONS, new JsonArray());
-
-        // Adding block data
-        obj.addProperty(KEY_REF_BLOCK_NUM, blockData.getRefBlockNum());
-        obj.addProperty(KEY_REF_BLOCK_PREFIX, blockData.getRefBlockPrefix());
-
-        return obj;
-
     }
 
-    class TransactionSerializer implements JsonSerializer<TransferOperation> {
+    public static class TransferSerializer implements JsonSerializer<TransferOperation> {
 
         @Override
-        public JsonElement serialize(TransferOperation transferOperation, Type type, JsonSerializationContext jsonSerializationContext) {
+        public JsonElement serialize(TransferOperation transfer, Type type, JsonSerializationContext jsonSerializationContext) {
-            return transferOperation.toJsonObject();
+            JsonArray arrayRep = new JsonArray();
+            arrayRep.add(transfer.getId());
+            arrayRep.add(transfer.toJsonObject());
+            return arrayRep;
+        }
+    }
+
+    /**
+     * This deserializer will work on any transfer operation serialized in the 'array form' used a lot in
+     * the Graphene Blockchain API.
+     *
+     * An example of this serialized form is the following:
+     *
+     *    [
+     *       0,
+     *       {
+     *           "fee": {
+     *               "amount": 264174,
+     *               "asset_id": "1.3.0"
+     *           },
+     *           "from": "1.2.138632",
+     *           "to": "1.2.129848",
+     *           "amount": {
+     *               "amount": 100,
+     *               "asset_id": "1.3.0"
+     *           },
+     *           "extensions": []
+     *       }
+     *    ]
+     *
+     * It will convert this data into a nice TransferOperation object.
+     */
+    public static class TransferDeserializer implements JsonDeserializer<TransferOperation> {
+
+        @Override
+        public TransferOperation deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException {
+            if(json.isJsonArray()){
+                // This block is used just to check if we are in the first step of the deserialization
+                // when we are dealing with an array.
+                JsonArray serializedTransfer = json.getAsJsonArray();
+                if(serializedTransfer.get(0).getAsInt() != OperationType.transfer_operation.ordinal()){
+                    // If the operation type does not correspond to a transfer operation, we return null
+                    return null;
+                }else{
+                    // Calling itself recursively, this is only done once, so there will be no problems.
+                    return context.deserialize(serializedTransfer.get(1), TransferOperation.class);
+                }
+            }else{
+                // This block is called in the second recursion and takes care of deserializing the
+                // transfer data itself.
+                JsonObject jsonObject = json.getAsJsonObject();
+
+                // Deserializing AssetAmount objects
+                AssetAmount amount = context.deserialize(jsonObject.get("amount"), AssetAmount.class);
+                AssetAmount fee = context.deserialize(jsonObject.get("fee"), AssetAmount.class);
+
+                // Deserializing UserAccount objects
+                UserAccount from = new UserAccount(jsonObject.get("from").getAsString());
+                UserAccount to = new UserAccount(jsonObject.get("to").getAsString());
+                TransferOperation transfer = new TransferOperation(from, to, amount, fee);
+                return transfer;
+            }
         }
     }
 }

src/main/java/com/luminiasoft/bitshares/TransferTransactionBuilder.java

@@ -46,7 +46,7 @@ public class TransferTransactionBuilder extends TransactionBuilder {
         return this;
     }
 
-    public TransferTransactionBuilder addOperation(Transfer transferOperation){
+    public TransferTransactionBuilder addOperation(TransferOperation transferOperation){
         if(operations == null){
             operations = new ArrayList<BaseOperation>();
         }
@@ -54,7 +54,7 @@ public class TransferTransactionBuilder extends TransactionBuilder {
     }
 
     @Override
-    public TransferOperation build() throws MalformedTransactionException {
+    public Transaction build() throws MalformedTransactionException {
         if(privateKey == null){
             throw new MalformedTransactionException("Missing private key information");
         }else if(blockData == null){
@@ -73,14 +73,14 @@ public class TransferTransactionBuilder extends TransactionBuilder {
             if(transferAmount == null){
                 throw new MalformedTransactionException("Missing transfer amount information");
             }
-            Transfer transferOperation;
+            TransferOperation transferOperation;
             if(feeAmount == null){
-                transferOperation = new Transfer(sourceAccount, destinationAccount, transferAmount);
+                transferOperation = new TransferOperation(sourceAccount, destinationAccount, transferAmount);
             }else{
-                transferOperation = new Transfer(sourceAccount, destinationAccount, transferAmount, feeAmount);
+                transferOperation = new TransferOperation(sourceAccount, destinationAccount, transferAmount, feeAmount);
             }
             operations.add(transferOperation);
         }
-        return new TransferOperation(privateKey, blockData, operations);
+        return new Transaction(privateKey, blockData, operations);
     }
 }

src/main/java/com/luminiasoft/bitshares/models/HistoricalTransfer.java

@@ -1,8 +1,6 @@
 package com.luminiasoft.bitshares.models;
 
-import com.luminiasoft.bitshares.BaseOperation;
+import com.luminiasoft.bitshares.TransferOperation;
-import com.luminiasoft.bitshares.GrapheneObject;
-import com.luminiasoft.bitshares.Transfer;
 
 /**
  * This class offers support to deserialization of transfer operations received by the API
@@ -13,7 +11,7 @@ import com.luminiasoft.bitshares.Transfer;
  */
 public class HistoricalTransfer {
     public String id;
-    public Transfer op;
+    public TransferOperation op;
     public Object[] result;
     public long block_num;
     public long trx_in_block;

src/main/java/com/luminiasoft/bitshares/ws/GetRelativeAccountHistory.java

@@ -5,7 +5,7 @@ import com.google.gson.GsonBuilder;
 import com.google.gson.reflect.TypeToken;
 import com.luminiasoft.bitshares.AssetAmount;
 import com.luminiasoft.bitshares.RPC;
-import com.luminiasoft.bitshares.Transfer;
+import com.luminiasoft.bitshares.TransferOperation;
 import com.luminiasoft.bitshares.UserAccount;
 import com.luminiasoft.bitshares.interfaces.WitnessResponseListener;
 import com.luminiasoft.bitshares.models.ApiCall;
@@ -119,7 +119,7 @@ public class GetRelativeAccountHistory extends WebSocketAdapter {
                 System.out.println(frame.getPayloadText());
                 Type RelativeAccountHistoryResponse = new TypeToken<WitnessResponse<List<HistoricalTransfer>>>(){}.getType();
                 GsonBuilder gsonBuilder = new GsonBuilder();
-                gsonBuilder.registerTypeAdapter(Transfer.class, new Transfer.TransferDeserializer());
+                gsonBuilder.registerTypeAdapter(TransferOperation.class, new TransferOperation.TransferDeserializer());
                 gsonBuilder.registerTypeAdapter(AssetAmount.class, new AssetAmount.AssetDeserializer());
                 WitnessResponse<List<HistoricalTransfer>> transfersResponse = gsonBuilder.create().fromJson(response, RelativeAccountHistoryResponse);
                 mListener.onSuccess(transfersResponse);

src/main/java/com/luminiasoft/bitshares/ws/TransactionBroadcastSequence.java

@@ -3,7 +3,7 @@ package com.luminiasoft.bitshares.ws;
 import com.google.gson.Gson;
 import com.google.gson.reflect.TypeToken;
 import com.luminiasoft.bitshares.*;
-import com.luminiasoft.bitshares.TransferOperation;
+import com.luminiasoft.bitshares.Transaction;
 import com.luminiasoft.bitshares.interfaces.WitnessResponseListener;
 import com.luminiasoft.bitshares.models.ApiCall;
 import com.luminiasoft.bitshares.models.BaseResponse;
@@ -24,7 +24,7 @@ import java.util.Map;
 import java.util.TimeZone;
 
 /**
- * Class that will handle the transferOperation publication procedure.
+ * Class that will handle the transaction publication procedure.
  */
 public class TransactionBroadcastSequence extends WebSocketAdapter {
     private final String TAG = this.getClass().getName();
@@ -35,7 +35,7 @@ public class TransactionBroadcastSequence extends WebSocketAdapter {
     private final static int BROADCAST_TRANSACTION = 4;
     public final static int EXPIRATION_TIME = 30;
 
-    private TransferOperation transferOperation;
+    private Transaction transaction;
     private long expirationTime;
     private String headBlockId;
     private long headBlockNumber;
@@ -47,13 +47,13 @@ public class TransactionBroadcastSequence extends WebSocketAdapter {
 
     /**
      * Constructor of this class. The ids required
-     * @param transferOperation: The transferOperation to be broadcasted.
+     * @param transaction: The transaction to be broadcasted.
      * @param listener: A class implementing the WitnessResponseListener interface. This should
      *                be implemented by the party interested in being notified about the success/failure
-     *                of the transferOperation broadcast operation.
+     *                of the transaction broadcast operation.
      */
-    public TransactionBroadcastSequence(TransferOperation transferOperation, WitnessResponseListener listener){
+    public TransactionBroadcastSequence(Transaction transaction, WitnessResponseListener listener){
-        this.transferOperation = transferOperation;
+        this.transaction = transaction;
         this.mListener = listener;
     }
 
@@ -102,14 +102,14 @@ public class TransactionBroadcastSequence extends WebSocketAdapter {
                 headBlockNumber = dynamicProperties.head_block_number;
 
                 ArrayList<Serializable> transactionList = new ArrayList<>();
-                transactionList.add(transferOperation);
+                transactionList.add(transaction);
                 ApiCall call = new ApiCall(broadcastApiId,
                         RPC.CALL_BROADCAST_TRANSACTION,
                         transactionList,
                         "2.0",
                         currentId);
 
-                // Finally sending transferOperation
+                // Finally sending transaction
                 websocket.sendText(call.toJsonString());
             }else if(baseResponse.id >= BROADCAST_TRANSACTION){
                 Type WitnessResponseType = new TypeToken<WitnessResponse<String>>(){}.getType();
@@ -131,18 +131,18 @@ public class TransactionBroadcastSequence extends WebSocketAdapter {
                         * with ONE transfer operation.
                         */
                         retries++;
-                        List<BaseOperation> operations = this.transferOperation.getOperations();
+                        List<BaseOperation> operations = this.transaction.getOperations();
-                        Transfer transfer = (Transfer) operations.get(0);
+                        TransferOperation transfer = (TransferOperation) operations.get(0);
-                        transferOperation = new TransferTransactionBuilder()
+                        transaction = new TransferTransactionBuilder()
                                 .setSource(transfer.getFrom())
                                 .setDestination(transfer.getTo())
                                 .setAmount(transfer.getAmount())
                                 .setFee(transfer.getFee())
                                 .setBlockData(new BlockData(headBlockNumber, headBlockId, expirationTime + EXPIRATION_TIME))
-                                .setPrivateKey(transferOperation.getPrivateKey())
+                                .setPrivateKey(transaction.getPrivateKey())
                                 .build();
                         ArrayList<Serializable> transactionList = new ArrayList<>();
-                        transactionList.add(transferOperation);
+                        transactionList.add(transaction);
                         ApiCall call = new ApiCall(broadcastApiId,
                                 RPC.CALL_BROADCAST_TRANSACTION,
                                 transactionList,