Summary

Add the reducedData platform preference.

Problem

Users on a limited-data network will often request applications to minimize internet traffic. The reducedData preference allows JavaFX applications to detect this user request.

Solution

The reducedData preference corresponds to the following OS settings:

Windows: Settings -> Network and Internet -> Ethernet/WiFi -> Metered connection

macOS: Settings -> Network -> Ethernet/WiFi -> Network Settings -> Low data mode

Ubuntu: Settings -> Network -> Wired/WiFi -> Metered connection

Specification

--- a/modules/javafx.graphics/src/main/java/javafx/application/Platform.java
+++ b/modules/javafx.graphics/src/main/java/javafx/application/Platform.java
@@ -498,6 +498,7 @@
      *         <tr><td>{@code Windows.UIColor.AccentLight3}</td><td>{@link Color}</td></tr>
      *         <tr><td>{@code Windows.UISettings.AdvancedEffectsEnabled}</td><td>{@link Boolean}</td></tr>
      *         <tr><td>{@code Windows.UISettings.AutoHideScrollBars}</td><td>{@link Boolean}</td></tr>
+     *         <tr><td>{@code Windows.NetworkInformation.InternetCostType}</td><td>{@link String}</td></tr>
      *         <tr></tr>
      *     </tbody>
      * </table>
@@ -553,6 +554,8 @@
      *         <tr><td>{@code macOS.NSWorkspace.accessibilityDisplayShouldReduceMotion}</td><td>{@link Boolean}</td></tr>
      *         <tr><td>{@code macOS.NSWorkspace.accessibilityDisplayShouldReduceTransparency}</td><td>{@link Boolean}</td></tr>
      *         <tr><td>{@code macOS.NSScroller.preferredScrollerStyle}</td><td>{@link String}</td></tr>
+     *         <tr><td>{@code macOS.NWPathMonitor.currentPathConstrained}</td><td>{@link Boolean}</td></tr>
+     *         <tr><td>{@code macOS.NWPathMonitor.currentPathExpensive}</td><td>{@link Boolean}</td></tr>
      *         <tr></tr>
      *     </tbody>
      * </table>
@@ -580,6 +583,7 @@
      *         <tr><td>{@code GTK.success_color}</td><td>{@link Color}</td></tr>
      *         <tr><td>{@code GTK.enable_animations}</td><td>{@link Boolean}</td></tr>
      *         <tr><td>{@code GTK.overlay_scrolling}</td><td>{@link Boolean}</td></tr>
+     *         <tr><td>{@code GTK.network_metered}</td><td>{@link Boolean}</td></tr>
      *         <tr></tr>
      *     </tbody>
      * </table>
@@ -631,6 +635,20 @@

         boolean isReducedTransparency();

+        /**
+         * Specifies whether applications should minimize the amount of internet traffic, which users
+         * might request because they are on a metered network or a limited data plan.
+         * <p>
+         * If the platform does not report this preference, this property defaults to {@code false}.
+         *
+         * @return the {@code reducedData} property
+         * @defaultValue {@code false}
+         * @since 24
+         */
+        ReadOnlyBooleanProperty reducedDataProperty();
+
+        boolean isReducedData();
+
         /**
          * The platform color scheme, which specifies whether applications should prefer light text on
          * dark backgrounds, or dark text on light backgrounds.