Maintain backwards support for pre-3.2.0 peers by only including new file list message params when sending to newer peers.

These params are optional and the process will function without them, just less efficiently.

src/main/java/org/qortal/controller/arbitrary/ArbitraryDataFileListManager.java

@@ -29,6 +29,7 @@ public class ArbitraryDataFileListManager {
 
     private static ArbitraryDataFileListManager instance;
 
+    private static String MIN_PEER_VERSION_FOR_FILE_LIST_STATS = "3.2.0";
 
     /**
      * Map of recent incoming requests for ARBITRARY transaction data file lists.
@@ -488,6 +489,12 @@ public class ArbitraryDataFileListManager {
                         arbitraryDataFileListMessage.setRequestHops(++requestHops);
                     }
 
+                    // Remove optional parameters if the requesting peer doesn't support it yet
+                    // A message with less statistical data is better than no message at all
+                    if (!requestingPeer.isAtLeastVersion(MIN_PEER_VERSION_FOR_FILE_LIST_STATS)) {
+                        arbitraryDataFileListMessage.removeOptionalStats();
+                    }
+
                     // Forward to requesting peer
                     LOGGER.debug("Forwarding file list with {} hashes to requesting peer: {}", hashes.size(), requestingPeer);
                     if (!requestingPeer.sendMessage(arbitraryDataFileListMessage)) {
@@ -594,6 +601,13 @@ public class ArbitraryDataFileListManager {
             ArbitraryDataFileListMessage arbitraryDataFileListMessage = new ArbitraryDataFileListMessage(signature,
                     hashes, NTP.getTime(), 0, ourAddress, true);
             arbitraryDataFileListMessage.setId(message.getId());
+
+            // Remove optional parameters if the requesting peer doesn't support it yet
+            // A message with less statistical data is better than no message at all
+            if (!peer.isAtLeastVersion(MIN_PEER_VERSION_FOR_FILE_LIST_STATS)) {
+                arbitraryDataFileListMessage.removeOptionalStats();
+            }
+
             if (!peer.sendMessage(arbitraryDataFileListMessage)) {
                 LOGGER.debug("Couldn't send list of hashes");
                 peer.disconnect("failed to send list of hashes");

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

@@ -22,10 +22,10 @@ public class ArbitraryDataFileListMessage extends Message {
 
 	private final byte[] signature;
 	private final List<byte[]> hashes;
-	private final Long requestTime;
+	private Long requestTime;
 	private Integer requestHops;
-	private final String peerAddress;
+	private String peerAddress;
-	private final boolean isRelayPossible;
+	private Boolean isRelayPossible;
 
 
 	public ArbitraryDataFileListMessage(byte[] signature, List<byte[]> hashes, Long requestTime,
@@ -109,7 +109,7 @@ public class ArbitraryDataFileListMessage extends Message {
 				bytes.write(hash);
 			}
 
-			if (this.requestTime == null) { // Just in case
+			if (this.requestTime == null) { // To maintain backwards support
 				return bytes.toByteArray();
 			}
 
@@ -136,15 +136,26 @@ public class ArbitraryDataFileListMessage extends Message {
 		return clone;
 	}
 
+	public void removeOptionalStats() {
+		this.requestTime = null;
+		this.requestHops = null;
+		this.peerAddress = null;
+		this.isRelayPossible = null;
+	}
+
 	public Long getRequestTime() {
 		return this.requestTime;
 	}
 
+	public void setRequestTime(Long requestTime) {
+		this.requestTime = requestTime;
+	}
+
 	public Integer getRequestHops() {
 		return this.requestHops;
 	}
 
-	public void setRequestHops(int requestHops) {
+	public void setRequestHops(Integer requestHops) {
 		this.requestHops = requestHops;
 	}
 
@@ -152,8 +163,16 @@ public class ArbitraryDataFileListMessage extends Message {
 		return this.peerAddress;
 	}
 
-	public boolean isRelayPossible() {
+	public void setPeerAddress(String peerAddress) {
+		this.peerAddress = peerAddress;
+	}
+
+	public Boolean isRelayPossible() {
 		return this.isRelayPossible;
 	}
 
+	public void setIsRelayPossible(Boolean isRelayPossible) {
+		this.isRelayPossible = isRelayPossible;
+	}
+
 }