Create GetBlocksRequestHandler's reply list once

Previously, the onGetBlocksRequest method created an ArrayList and two
LinkedList before creating the GetBlocksResponse. The first two lists
were never used. PR bisq-network#6947 introduced the second LinkedList creation.
With this change, the GetBlocksRequestHandler only creates a single
LinkedList.

core/src/main/java/bisq/core/dao/node/full/network/GetBlocksRequestHandler.java

@@ -92,11 +92,10 @@ public GetBlocksRequestHandler(NetworkNode networkNode, DaoStateService daoState
     public void onGetBlocksRequest(GetBlocksRequest getBlocksRequest, Connection connection) {
         long ts = System.currentTimeMillis();
         // We limit number of blocks to 3000 which is about 3 weeks and about 5 MB on data
-        List<Block> blocks = daoStateService.getBlocksFromBlockHeight(getBlocksRequest.getFromBlockHeight());
-        List<RawBlock> rawBlocks = new LinkedList<>(blocks).stream()
+        List<RawBlock> rawBlocks = daoStateService.getBlocksFromBlockHeightStream(getBlocksRequest.getFromBlockHeight(), 3000)
                 .map(RawBlock::fromBlock)
-                .limit(3000)
-                .collect(Collectors.toList());
+                .collect(Collectors.toCollection(LinkedList::new));
+
         GetBlocksResponse getBlocksResponse = new GetBlocksResponse(rawBlocks, getBlocksRequest.getNonce());
         log.info("Received GetBlocksRequest from {} for blocks from height {}. " +
                         "Building GetBlocksResponse with {} blocks took {} ms.",

core/src/main/java/bisq/core/dao/state/DaoStateService.java

@@ -349,12 +349,22 @@ public long getBlockTime(int height) {
     }
 
     public List<Block> getBlocksFromBlockHeight(int fromBlockHeight) {
+        return getBlocksFromBlockHeight(fromBlockHeight, Integer.MAX_VALUE);
+    }
+
+    public List<Block> getBlocksFromBlockHeight(int fromBlockHeight, int numMaxBlocks) {
+        return getBlocksFromBlockHeightStream(fromBlockHeight, numMaxBlocks)
+                .collect(Collectors.toCollection(LinkedList::new));
+    }
+
+    public Stream<Block> getBlocksFromBlockHeightStream(int fromBlockHeight, int numMaxBlocks) {
+        // We limit requests to numMaxBlocks blocks, to avoid performance issues and too
+        // large network data in case a node requests too far back in history.
         return getBlocks().stream()
                 .filter(block -> block.getHeight() >= fromBlockHeight)
-                .collect(Collectors.toList());
+                .limit(numMaxBlocks);
     }
 
-
     ///////////////////////////////////////////////////////////////////////////////////////////
     // Genesis
     ///////////////////////////////////////////////////////////////////////////////////////////