HUEditorViewBuffer_HighVolume: sorting support (partial)

src/main/java/de/metas/ui/web/handlingunits/HUEditorViewBuffer_HighVolume.java

@@ -5,6 +5,7 @@
 import java.util.List;
 import java.util.Objects;
 import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.function.UnaryOperator;
 import java.util.stream.Stream;
@@ -57,7 +58,10 @@ public class HUEditorViewBuffer_HighVolume implements HUEditorViewBuffer
 
 	private final HUEditorViewRepository huEditorRepo;
 	private final ImmutableList<DocumentFilter> stickyFilters;
+
 	private final AtomicReference<ViewRowIdsOrderedSelection> defaultSelectionRef;
+	private final transient ConcurrentHashMap<ImmutableList<DocumentQueryOrderBy>, ViewRowIdsOrderedSelection> selectionsByOrderBys = new ConcurrentHashMap<>();
+
 	private final CCache<DocumentId, HUEditorRow> cache_huRowsById = CCache.newLRUCache(I_M_HU.Table_Name + "#HUEditorRows#by#Id", 100, 2);
 
 	HUEditorViewBuffer_HighVolume(
@@ -85,12 +89,32 @@ private ViewRowIdsOrderedSelection getDefaultSelection()
 	{
 		return defaultSelectionRef.get();
 	}
+
+	private ViewRowIdsOrderedSelection getSelection(final List<DocumentQueryOrderBy> orderBys)
+	{
+		final ViewRowIdsOrderedSelection defaultSelection = getDefaultSelection();
+
+		if (orderBys == null || orderBys.isEmpty())
+		{
+			return defaultSelection;
+		}
+
+		if (Objects.equals(defaultSelection.getOrderBys(), orderBys))
+		{
+			return defaultSelection;
+		}
+
+		return selectionsByOrderBys.computeIfAbsent(ImmutableList.copyOf(orderBys), orderBysImmutable -> huEditorRepo.createSelectionFromSelection(defaultSelection, orderBysImmutable));
+	}
+
 
 	/** @return true if selection was really changed */
-	private boolean changeDefaultSelection(final UnaryOperator<ViewRowIdsOrderedSelection> mapper)
+	private boolean changeSelection(final UnaryOperator<ViewRowIdsOrderedSelection> mapper)
 	{
 		final ViewRowIdsOrderedSelection defaultSelectionOld = defaultSelectionRef.get();
 		final ViewRowIdsOrderedSelection defaultSelectionNew = defaultSelectionRef.updateAndGet(mapper);
+		selectionsByOrderBys.clear(); // invalidate all the other selections, let it recompute when needed
+
 		return !Objects.equals(defaultSelectionOld, defaultSelectionNew);
 	}
 
@@ -127,7 +151,7 @@ public boolean addHUIds(final Collection<Integer> huIdsToAdd)
 			return false;
 		}
 
-		return changeDefaultSelection(defaultSelection -> huEditorRepo.addRowIdsToSelection(defaultSelection, rowIdsToAdd));
+		return changeSelection(defaultSelection -> huEditorRepo.addRowIdsToSelection(defaultSelection, rowIdsToAdd));
 	}
 
 	@Override
@@ -142,7 +166,7 @@ public boolean removeHUIds(final Collection<Integer> huIdsToRemove)
 
 		rowIdsToRemove.forEach(rowId -> cache_huRowsById.remove(rowId));
 
-		return changeDefaultSelection(defaultSelection -> huEditorRepo.removeRowIdsFromSelection(defaultSelection, rowIdsToRemove));
+		return changeSelection(defaultSelection -> huEditorRepo.removeRowIdsFromSelection(defaultSelection, rowIdsToRemove));
 	}
 
 	@Override
@@ -215,23 +239,6 @@ public Stream<HUEditorRow> streamPage(
 				.stream();
 	}
 
-	private ViewRowIdsOrderedSelection getSelection(final List<DocumentQueryOrderBy> orderBys)
-	{
-		final ViewRowIdsOrderedSelection defaultSelection = getDefaultSelection();
-
-		if (orderBys == null || orderBys.isEmpty())
-		{
-			return defaultSelection;
-		}
-
-		if (!Objects.equals(orderBys, defaultSelection.getOrderBys()))
-		{
-			throw new UnsupportedOperationException("Sorting is not supported");
-		}
-
-		return defaultSelection;
-	}
-
 	private PageFetcher<Integer> huIdsPageFetcher(final List<DocumentQueryOrderBy> orderBys)
 	{
 		final ViewRowIdsOrderedSelection selection = getSelection(orderBys);

src/main/java/de/metas/ui/web/handlingunits/HUEditorViewRepository.java

@@ -38,6 +38,10 @@ public interface HUEditorViewRepository
 {
 	void invalidateCache();
 
+	ViewRowIdsOrderedSelection createSelection(ViewId viewId, List<DocumentFilter> filters, List<DocumentQueryOrderBy> orderBys);
+
+	ViewRowIdsOrderedSelection createSelectionFromSelection(ViewRowIdsOrderedSelection fromSelection, List<DocumentQueryOrderBy> orderBys);
+
 	List<HUEditorRow> retrieveHUEditorRows(Set<Integer> huIds, HUEditorRowFilter filter);
 
 	/**
@@ -52,8 +56,6 @@ public interface HUEditorViewRepository
 
 	Page<Integer> retrieveHUIdsPage(ViewRowIdsOrderedSelection selection, int firstRow, int maxRows);
 
-	ViewRowIdsOrderedSelection createSelection(ViewId viewId, List<DocumentFilter> filters, List<DocumentQueryOrderBy> orderBys);
-
 	ViewRowIdsOrderedSelection addRowIdsToSelection(ViewRowIdsOrderedSelection selection, DocumentIdsSelection rowIdsToAdd);
 
 	ViewRowIdsOrderedSelection removeRowIdsFromSelection(ViewRowIdsOrderedSelection selection, DocumentIdsSelection rowIdsToRemove);

src/main/java/de/metas/ui/web/handlingunits/SqlHUEditorViewRepository.java

@@ -107,7 +107,6 @@ public class SqlHUEditorViewRepository implements HUEditorViewRepository
 	private final ViewRowIdsOrderedSelectionFactory viewSelectionFactory;
 	private final SqlViewSelectData sqlViewSelect;
 
-
 	@Builder
 	private SqlHUEditorViewRepository(
 			@NonNull final WindowId windowId,
@@ -558,6 +557,13 @@ public ViewRowIdsOrderedSelection createSelection(final ViewId viewId, final Lis
 		return viewSelectionFactory.createOrderedSelection(viewEvalCtx, viewId, filters, orderBys);
 	}
 
+	@Override
+	public ViewRowIdsOrderedSelection createSelectionFromSelection(final ViewRowIdsOrderedSelection fromSelection, final List<DocumentQueryOrderBy> orderBys)
+	{
+		final ViewEvaluationCtx viewEvalCtx = ViewEvaluationCtx.of(Env.getCtx());
+		return viewSelectionFactory.createOrderedSelectionFromSelection(viewEvalCtx, fromSelection, orderBys);
+	}
+
 	@Override
 	public ViewRowIdsOrderedSelection addRowIdsToSelection(final ViewRowIdsOrderedSelection selection, final DocumentIdsSelection rowIdsToAdd)
 	{