Added support for file hashes to optionally be included in GetArbitraryDataFileListMessage.

Needs testing on testnet, as the majority of nodes need to update before the hashes can be used.

src/main/java/org/qortal/network/message/GetArbitraryDataFileListMessage.java

@@ -3,11 +3,14 @@ package org.qortal.network.message;
 import com.google.common.primitives.Ints;
 import com.google.common.primitives.Longs;
 import org.qortal.transform.Transformer;
+import org.qortal.transform.transaction.TransactionTransformer;
 
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.UnsupportedEncodingException;
 import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.List;
 
 import static org.qortal.transform.Transformer.INT_LENGTH;
 import static org.qortal.transform.Transformer.LONG_LENGTH;
@@ -15,19 +18,22 @@ import static org.qortal.transform.Transformer.LONG_LENGTH;
 public class GetArbitraryDataFileListMessage extends Message {
 
 	private static final int SIGNATURE_LENGTH = Transformer.SIGNATURE_LENGTH;
+	private static final int HASH_LENGTH = TransactionTransformer.SHA256_LENGTH;
 
 	private final byte[] signature;
+	private List<byte[]> hashes;
 	private final long requestTime;
 	private int requestHops;
 
-	public GetArbitraryDataFileListMessage(byte[] signature, long requestTime, int requestHops) {
-		this(-1, signature, requestTime, requestHops);
+	public GetArbitraryDataFileListMessage(byte[] signature, List<byte[]> hashes, long requestTime, int requestHops) {
+		this(-1, signature, hashes, requestTime, requestHops);
 	}
 
-	private GetArbitraryDataFileListMessage(int id, byte[] signature, long requestTime, int requestHops) {
+	private GetArbitraryDataFileListMessage(int id, byte[] signature, List<byte[]> hashes, long requestTime, int requestHops) {
 		super(id, MessageType.GET_ARBITRARY_DATA_FILE_LIST);
 
 		this.signature = signature;
+		this.hashes = hashes;
 		this.requestTime = requestTime;
 		this.requestHops = requestHops;
 	}
@@ -36,10 +42,11 @@ public class GetArbitraryDataFileListMessage extends Message {
 		return this.signature;
 	}
 
-	public static Message fromByteBuffer(int id, ByteBuffer bytes) throws UnsupportedEncodingException {
-		if (bytes.remaining() != SIGNATURE_LENGTH + LONG_LENGTH + INT_LENGTH)
-			return null;
+	public List<byte[]> getHashes() {
+		return this.hashes;
+	}
 
+	public static Message fromByteBuffer(int id, ByteBuffer bytes) throws UnsupportedEncodingException {
 		byte[] signature = new byte[SIGNATURE_LENGTH];
 
 		bytes.get(signature);
@@ -48,7 +55,23 @@ public class GetArbitraryDataFileListMessage extends Message {
 
 		int requestHops = bytes.getInt();
 
-		return new GetArbitraryDataFileListMessage(id, signature, requestTime, requestHops);
+		List<byte[]> hashes = null;
+		if (bytes.hasRemaining()) {
+			int hashCount = bytes.getInt();
+
+			if (bytes.remaining() != hashCount * HASH_LENGTH) {
+				return null;
+			}
+
+			hashes = new ArrayList<>();
+			for (int i = 0; i < hashCount; ++i) {
+				byte[] hash = new byte[HASH_LENGTH];
+				bytes.get(hash);
+				hashes.add(hash);
+			}
+		}
+
+		return new GetArbitraryDataFileListMessage(id, signature, hashes, requestTime, requestHops);
 	}
 
 	@Override
@@ -62,6 +85,14 @@ public class GetArbitraryDataFileListMessage extends Message {
 
 			bytes.write(Ints.toByteArray(this.requestHops));
 
+			if (this.hashes != null) {
+				bytes.write(Ints.toByteArray(this.hashes.size()));
+
+				for (byte[] hash : this.hashes) {
+					bytes.write(hash);
+				}
+			}
+
 			return bytes.toByteArray();
 		} catch (IOException e) {
 			return null;