Use an alternative version of Serialization.serializeSizedString() and Serialization.deserializeSizedString() for the new ARBITRARY transaction additions.

The modifications made to these methods were causing issues with other transaction types that were expecting blank strings instead of null. To keep risk to a minimum, I have split into two different sets of functions until there is more time to unify them.

src/main/java/org/qortal/transform/transaction/ArbitraryTransactionTransformer.java

@@ -106,9 +106,9 @@ public class ArbitraryTransactionTransformer extends TransactionTransformer {
 		if (version >= 5) {
 			nonce = byteBuffer.getInt();
 
-			name = Serialization.deserializeSizedString(byteBuffer, Name.MAX_NAME_SIZE);
+			name = Serialization.deserializeSizedStringV2(byteBuffer, Name.MAX_NAME_SIZE);
 
-			identifier = Serialization.deserializeSizedString(byteBuffer, ArbitraryTransaction.MAX_IDENTIFIER_LENGTH);
+			identifier = Serialization.deserializeSizedStringV2(byteBuffer, ArbitraryTransaction.MAX_IDENTIFIER_LENGTH);
 
 			method =  ArbitraryTransactionData.Method.valueOf(byteBuffer.getInt());
 
@@ -203,9 +203,9 @@ public class ArbitraryTransactionTransformer extends TransactionTransformer {
 			if (arbitraryTransactionData.getVersion() >= 5) {
 				bytes.write(Ints.toByteArray(arbitraryTransactionData.getNonce()));
 
-				Serialization.serializeSizedString(bytes, arbitraryTransactionData.getName());
+				Serialization.serializeSizedStringV2(bytes, arbitraryTransactionData.getName());
 
-				Serialization.serializeSizedString(bytes, arbitraryTransactionData.getIdentifier());
+				Serialization.serializeSizedStringV2(bytes, arbitraryTransactionData.getIdentifier());
 
 				bytes.write(Ints.toByteArray(arbitraryTransactionData.getMethod().value));
 
@@ -274,9 +274,9 @@ public class ArbitraryTransactionTransformer extends TransactionTransformer {
 			if (arbitraryTransactionData.getVersion() >= 5) {
 				bytes.write(Ints.toByteArray(arbitraryTransactionData.getNonce()));
 
-				Serialization.serializeSizedString(bytes, arbitraryTransactionData.getName());
+				Serialization.serializeSizedStringV2(bytes, arbitraryTransactionData.getName());
 
-				Serialization.serializeSizedString(bytes, arbitraryTransactionData.getIdentifier());
+				Serialization.serializeSizedStringV2(bytes, arbitraryTransactionData.getIdentifier());
 
 				bytes.write(Ints.toByteArray(arbitraryTransactionData.getMethod().value));
 

src/main/java/org/qortal/utils/Serialization.java

@@ -100,7 +100,50 @@ public class Serialization {
 		return bytes;
 	}
 
+	/**
+	 * Original serializeSizedString() method used in various transaction types
+	 * @param bytes
+	 * @param string
+	 * @throws UnsupportedEncodingException
+	 * @throws IOException
+	 */
 	public static void serializeSizedString(ByteArrayOutputStream bytes, String string) throws UnsupportedEncodingException, IOException {
+		byte[] stringBytes = string.getBytes(StandardCharsets.UTF_8);
+		bytes.write(Ints.toByteArray(stringBytes.length));
+		bytes.write(stringBytes);
+	}
+
+	/**
+	 * Original deserializeSizedString() method used in various transaction types
+	 * @param byteBuffer
+	 * @param maxSize
+	 * @return
+	 * @throws TransformationException
+	 */
+	public static String deserializeSizedString(ByteBuffer byteBuffer, int maxSize) throws TransformationException {
+		int size = byteBuffer.getInt();
+		if (size > maxSize)
+			throw new TransformationException("Serialized string too long");
+
+		if (size > byteBuffer.remaining())
+			throw new TransformationException("Byte data too short for serialized string");
+
+		byte[] bytes = new byte[size];
+		byteBuffer.get(bytes);
+
+		return new String(bytes, StandardCharsets.UTF_8);
+	}
+
+	/**
+	 * Alternate version of serializeSizedString() added for ARBITRARY transactions.
+	 * These two methods can ultimately be merged together once unit tests can
+	 * confirm that they process data identically.
+	 * @param bytes
+	 * @param string
+	 * @throws UnsupportedEncodingException
+	 * @throws IOException
+	 */
+	public static void serializeSizedStringV2(ByteArrayOutputStream bytes, String string) throws UnsupportedEncodingException, IOException {
 		byte[] stringBytes = null;
 		int stringBytesLength = 0;
 
@@ -114,7 +157,17 @@ public class Serialization {
 		}
 	}
 
-	public static String deserializeSizedString(ByteBuffer byteBuffer, int maxSize) throws TransformationException {
+	/**
+	 * Alternate version of serializeSizedString() added for ARBITRARY transactions.
+	 * The main difference is that blank strings are returned as null.
+	 * These two methods can ultimately be merged together once any differences are
+	 * solved, and unit tests can confirm that they process data identically.
+	 * @param byteBuffer
+	 * @param maxSize
+	 * @return
+	 * @throws TransformationException
+	 */
+	public static String deserializeSizedStringV2(ByteBuffer byteBuffer, int maxSize) throws TransformationException {
 		int size = byteBuffer.getInt();
 		if (size > maxSize)
 			throw new TransformationException("Serialized string too long");