Don't add data if it's been removed recently

p2p/src/main/java/bisq/network/p2p/storage/P2PDataStorage.java

@@ -75,6 +75,7 @@
 import java.security.KeyPair;
 import java.security.PublicKey;
 
+import java.util.ArrayList;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.HashSet;
@@ -120,6 +121,7 @@ public class P2PDataStorage implements MessageListener, ConnectionListener, Pers
 
     private final Set<AppendOnlyDataStoreListener> appendOnlyDataStoreListeners = new CopyOnWriteArraySet<>();
     private final Set<ProtectedDataStoreListener> protectedDataStoreListeners = new CopyOnWriteArraySet<>();
+    private List<ByteArray> recentlyRemovedMessages = new ArrayList<>();
 
 
     ///////////////////////////////////////////////////////////////////////////////////////////
@@ -349,6 +351,13 @@ public boolean addProtectedStorageEntry(ProtectedStorageEntry protectedStorageEn
                 && checkSignature(protectedStorageEntry)
                 && sequenceNrValid;
 
+        synchronized (recentlyRemovedMessages) {
+            if (recentlyRemovedMessages.contains(hashOfPayload)) {
+                log.trace("We ignore this message as we received a remove command for this very data only recently");
+                return false;
+            }
+        }
+
         boolean containsKey = map.containsKey(hashOfPayload);
         if (containsKey)
             result = result && checkIfStoredDataPubKeyMatchesNewDataPubKey(protectedStorageEntry.getOwnerPubKey(), hashOfPayload);
@@ -576,6 +585,13 @@ public void removeProtectedDataStoreListener(ProtectedDataStoreListener listener
 
     private void doRemoveProtectedExpirableData(ProtectedStorageEntry protectedStorageEntry, ByteArray hashOfPayload) {
         map.remove(hashOfPayload);
+
+        synchronized (recentlyRemovedMessages) {
+            recentlyRemovedMessages.add(hashOfPayload);
+            while (recentlyRemovedMessages.size() > 500)
+                recentlyRemovedMessages.remove(0);
+        }
+
         log.trace("Data removed from our map. We broadcast the message to our peers.");
         hashMapChangedListeners.stream().forEach(e -> e.onRemoved(protectedStorageEntry));
     }