Batch rich HTML updates

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- `RichHtmlView#setHtml(String, HtmlRenderOptions)`, which updates the HTML and the render options with a single model rebuild instead of one per property.
+
 ## [0.1.0] - 2026-07-14
 
 ### Added

src/main/java/org/jabref/htmltonode/rich/RichHtmlView.java

@@ -22,22 +22,24 @@
 /// `org.jabref.htmltonode.HtmlView`, but with native text selection, caret navigation, and
 /// accessibility. The area scrolls itself; do not wrap this view in a `ScrollPane`.
 ///
-/// Re-renders whenever [#htmlProperty()] or [#optionsProperty()] changes. Must be used on the
-/// JavaFX application thread. Requires the `jfx.incubator.richtext` module at runtime.
+/// Re-renders whenever [#htmlProperty()] or [#optionsProperty()] changes, except while
+/// [#setHtml(String,HtmlRenderOptions)] updates both — that renders once, at the end. Must be used
+/// on the JavaFX application thread. Requires the `jfx.incubator.richtext` module at runtime.
 public class RichHtmlView extends StackPane {
 
     private final RichTextArea area = new HtmlRichTextArea();
     private final StringProperty html = new SimpleStringProperty(this, "html", "");
     private final ObjectProperty<HtmlRenderOptions> options =
             new SimpleObjectProperty<>(this, "options", HtmlRenderOptions.defaults());
+    private boolean updatesAreBatched;
 
     /// Creates an empty view with [HtmlRenderOptions#defaults()].
     public RichHtmlView() {
         setAlignment(Pos.TOP_LEFT);
         getStylesheets().add(HtmlToNode.stylesheet());
         getChildren().add(area);
-        html.addListener((observable, oldValue, newValue) -> rerender());
-        options.addListener((observable, oldValue, newValue) -> rerender());
+        html.addListener((observable, oldValue, newValue) -> rerenderIfNeeded());
+        options.addListener((observable, oldValue, newValue) -> rerenderIfNeeded());
         rerender();
     }
 
@@ -58,6 +60,24 @@ public final void setHtml(@Nullable String newHtml) {
         html.set(newHtml == null ? "" : newHtml);
     }
 
+    /// Updates the HTML content and render options in one model rebuild.
+    ///
+    /// @param newHtml the HTML content to render; `null` is treated as empty
+    /// @param newOptions the rendering options; `null` restores [HtmlRenderOptions#defaults()]
+    public final void setHtml(@Nullable String newHtml, @Nullable HtmlRenderOptions newOptions) {
+        HtmlRenderOptions effectiveOptions = newOptions == null ? HtmlRenderOptions.defaults() : newOptions;
+        updatesAreBatched = true;
+        try {
+            html.set(newHtml == null ? "" : newHtml);
+            options.set(effectiveOptions);
+        } finally {
+            // In the finally block so a throwing property listener cannot leave the rendered
+            // content out of sync with the already-updated properties.
+            updatesAreBatched = false;
+            rerender();
+        }
+    }
+
     /// The rendering options of this view. Setting a new value re-renders. Never `null`.
     ///
     /// @return the options property
@@ -138,4 +158,10 @@ private void rerender() {
         area.setModel(RichTextRenderer.buildModel(HtmlToNode.parse(getHtml(), renderOptions.baseUri()), renderOptions));
         RichTextRenderer.configure(area, renderOptions);
     }
+
+    private void rerenderIfNeeded() {
+        if (!updatesAreBatched) {
+            rerender();
+        }
+    }
 }

src/test/java/org/jabref/htmltonode/RichHtmlViewTest.java

@@ -2,11 +2,13 @@
 
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReference;
 
 import javafx.application.Platform;
 import javafx.scene.Scene;
 
+import org.jabref.htmltonode.HtmlRenderOptions;
 import org.jabref.htmltonode.rich.RichHtmlView;
 
 import org.junit.jupiter.api.BeforeAll;
@@ -63,6 +65,45 @@ void selectionFacadeReturnsSelectedText() throws Exception {
         assertEquals(java.util.Optional.of("First entry\nSecond one"), after.get());
     }
 
+    @Test
+    void setHtmlWithOptionsRebuildsModelOnce() throws Exception {
+        AtomicReference<Throwable> error = new AtomicReference<>();
+        AtomicInteger batchedRebuilds = new AtomicInteger();
+        AtomicInteger separateRebuilds = new AtomicInteger();
+        AtomicReference<String> renderedText = new AtomicReference<>();
+        CountDownLatch done = new CountDownLatch(1);
+
+        Platform.runLater(() -> {
+            try {
+                HtmlRenderOptions newOptions = HtmlRenderOptions.defaults().withBaseFontSize(19.0);
+
+                RichHtmlView batched = new RichHtmlView();
+                batched.getRichTextArea().modelProperty()
+                       .addListener((observable, oldValue, newValue) -> batchedRebuilds.incrementAndGet());
+                batched.setHtml("<p>Updated</p>", newOptions);
+                renderedText.set(batched.getRichTextArea().getModel().getPlainText(0));
+
+                RichHtmlView separate = new RichHtmlView();
+                separate.getRichTextArea().modelProperty()
+                        .addListener((observable, oldValue, newValue) -> separateRebuilds.incrementAndGet());
+                separate.setHtml("<p>Updated</p>");
+                separate.setOptions(newOptions);
+            } catch (Throwable t) {
+                error.set(t);
+            } finally {
+                done.countDown();
+            }
+        });
+
+        assertTrue(done.await(15, TimeUnit.SECONDS), "FX task timed out");
+        if (error.get() != null) {
+            throw new AssertionError("FX task failed", error.get());
+        }
+        assertEquals(1, batchedRebuilds.get(), "batched update should rebuild the model once");
+        assertEquals(2, separateRebuilds.get(), "separate setters rebuild the model per property");
+        assertEquals("Updated", renderedText.get());
+    }
+
     @Test
     void viewRendersHtmlIntoRichTextArea() throws Exception {
         AtomicReference<Throwable> error = new AtomicReference<>();