Changeset 17136 in josm for trunk

Timestamp:

2020-10-09T14:19:58+02:00 (4 years ago)

Author:

GerdP

Message:

see #19898: Performance improvements for DatasetMerger
Avoid to avoid to materialise unneeded copies of SubclassFilteredCollection

Location:

trunk/src/org/openstreetmap/josm

Files:

• data/osm/DataSetMerger.java (modified) (4 diffs)
• io/OsmServerBackreferenceReader.java (modified) (1 diff)

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

@@ -425 +425 @@
         }
         targetDataSet.update(() -> {
-            List<? extends OsmPrimitive> candidates = new ArrayList<>(targetDataSet.getNodes());
+            List<? extends OsmPrimitive> candidates = null;
             for (Node node: sourceDataSet.getNodes()) {
+                // lazy initialisation to improve performance, see #19898
+                if (candidates == null) {
+                    candidates = new ArrayList<>(targetDataSet.getNodes());
+                }
                 mergePrimitive(node, candidates);
                 if (progressMonitor != null) {
@@ -432 +436 @@
                 }
             }
-            candidates.clear();
-            candidates = new ArrayList<>(targetDataSet.getWays());
+            candidates = null;
             for (Way way: sourceDataSet.getWays()) {
+                // lazy initialisation to improve performance
+                if (candidates == null) {
+                    candidates = new ArrayList<>(targetDataSet.getWays());
+                }
                 mergePrimitive(way, candidates);
                 if (progressMonitor != null) {
@@ -440 +447 @@
                 }
             }
-            candidates.clear();
-            candidates = new ArrayList<>(targetDataSet.getRelations());
+            candidates = null;
             for (Relation relation: sourceDataSet.getRelations()) {
+                // lazy initialisation to improve performance
+                if (candidates == null) {
+                    candidates = new ArrayList<>(targetDataSet.getRelations());
+                }
                 mergePrimitive(relation, candidates);
                 if (progressMonitor != null) {
@@ -448 +458 @@
                 }
             }
-            candidates.clear();
+            candidates = null;
             fixReferences();
 

trunk/src/org/openstreetmap/josm/io/OsmServerBackreferenceReader.java

@@ -215 +215 @@
         progressMonitor.beginTask(null, 2);
         try {
-            Collection<Way> waysToCheck = new ArrayList<>(ds.getWays());
             if (isReadFull() || (primitiveType == OsmPrimitiveType.NODE && !isAllowIncompleteParentWays())) {
+                Collection<Way> waysToCheck = new ArrayList<>(ds.getWays());
                 for (Way way: waysToCheck) {
                     if (!way.isNew() && way.hasIncompleteNodes()) {