Changeset 18470 in josm for trunk/src/org

Timestamp:

2022-06-07T17:54:52+02:00 (2 years ago)

Author:

taylor.smock

Message:

Reduce memory allocations and CPU calls in Way#getNodePairs

This reduces memory allocations and CPU calls by ~33% for the method call
by setting the size of the list at construction time.

See #20716 comment:68.

File:

• trunk/src/org/openstreetmap/josm/data/osm/Way.java (modified) (1 diff)

trunk/src/org/openstreetmap/josm/data/osm/Way.java

@@ -157 +157 @@
      */
     public List<Pair<Node, Node>> getNodePairs(boolean sort) {
-        List<Pair<Node, Node>> chunkSet = new ArrayList<>();
+        // For a way of size n, there are n - 1 pairs (a -> b, b -> c, c -> d, etc., 4 nodes -> 3 pairs)
+        List<Pair<Node, Node>> chunkSet = new ArrayList<>(this.getNodesCount() - 1);
         if (isIncomplete()) return chunkSet;
         Node lastN = null;