Improve UI responsiveness when UpdatePricesJob is running on slower

computers

The change ensures that running asynchronously ClientInput.setDirty in
the display thread is not scheduled if the previous request has not yet
been executed and thus no backlog of requests arises.

Issue: portfolio-performance#5557
Co-authored-by: Stephan Wahlbrink <sw@wahlbrink.eu>
Co-authored-by: Andreas Buchen <andreas.buchen@gmail.com>

Author: wahlbrink

name.abuchen.portfolio.ui/src/name/abuchen/portfolio/ui/editor/ClientInput.java

@@ -83,6 +83,10 @@ public class ClientInput
     private List<Runnable> disposeJobs = new ArrayList<>();
     private List<ClientInputListener> listeners = new ArrayList<>();
 
+    private final Object pendingLock = new Object();
+    private boolean pendingDirty;
+    private boolean pendingRecalculate;
+
     @Inject
     private IEventBroker broker;
 
@@ -148,6 +152,37 @@ public void touch()
         setDirty(true, false);
     }
 
+    private void scheduleDirty(boolean recalculate)
+    {
+        if (Display.getDefault().getThread() == Thread.currentThread())
+        {
+            setDirty(true, recalculate);
+            return;
+        }
+        synchronized (pendingLock)
+        {
+            pendingRecalculate |= recalculate;
+            if (pendingDirty)
+                return; // asyncExec already queued; it will pick up the merged state
+            pendingDirty = true;
+        }
+        Display.getDefault().asyncExec(this::applyPendingDirty);
+    }
+
+    private void applyPendingDirty()
+    {
+        boolean recalculate;
+        synchronized (pendingLock)
+        {
+            if (!pendingDirty)
+                return; // consumed by a save() that ran before we fired
+            recalculate = pendingRecalculate;
+            pendingDirty = false;
+            pendingRecalculate = false;
+        }
+        setDirty(true, recalculate);
+    }
+
     private void setDirty(boolean isDirty, boolean recalculate)
     {
         this.isDirty = isDirty;
@@ -230,7 +265,21 @@ public void save(Shell shell)
                 storePreferences(false);
 
                 broker.post(UIConstants.Event.File.SAVED, clientFile.getAbsolutePath());
-                setDirty(false, false);
+
+                // Cancel any pending asyncExec dirty notification. If a background
+                // modification arrived during the save the on-disk file may not reflect
+                // it, so we conservatively remain dirty in that case.
+                boolean hadPendingModification;
+                boolean hadPendingRecalculate;
+                synchronized (pendingLock)
+                {
+                    hadPendingModification = pendingDirty;
+                    hadPendingRecalculate = pendingRecalculate;
+                    pendingDirty = false;
+                    pendingRecalculate = false;
+                }
+                setDirty(hadPendingModification, hadPendingRecalculate);
+
                 listeners.forEach(ClientInputListener::onSaved);
             }
             catch (IOException e)
@@ -269,7 +318,18 @@ public void doSaveAs(Shell shell, String extension, Set<SaveFlag> flags) // NOSO
                 storePreferences(true);
 
                 broker.post(UIConstants.Event.File.SAVED, clientFile.getAbsolutePath());
-                setDirty(false, false);
+
+                boolean hadPendingModification;
+                boolean hadPendingRecalculate;
+                synchronized (pendingLock)
+                {
+                    hadPendingModification = pendingDirty;
+                    hadPendingRecalculate = pendingRecalculate;
+                    pendingDirty = false;
+                    pendingRecalculate = false;
+                }
+                setDirty(hadPendingModification, hadPendingRecalculate);
+
                 listeners.forEach(ClientInputListener::onSaved);
             }
             catch (IOException e)
@@ -658,15 +718,7 @@ private void scheduleAutoSaveJob()
             // convenience: Client#markDirty can be called on any thread, but
             // ClientInputListener#onDirty will always be called on the UI
             // thread
-
-            if (Display.getDefault().getThread() == Thread.currentThread())
-            {
-                setDirty(true, recalculate);
-            }
-            else
-            {
-                Display.getDefault().asyncExec(() -> setDirty(true, recalculate));
-            }
+            scheduleDirty(recalculate);
         };
         client.addPropertyChangeListener(listener);
         disposeJobs.add(() -> client.removePropertyChangeListener(listener));