fix(footer): Use java.awt.Desktop as fallback for HostServices (#500)

This introduces a wrapper around HostServices/Desktop, the `HostServicesWrapper`. This abstraction hides what technology is used to open links in the system browser.

Co-authored-by: jdrueckert <[email protected]>

src/main/java/org/terasology/launcher/TerasologyLauncher.java

@@ -46,6 +46,7 @@
 import org.terasology.launcher.gui.javafx.ApplicationController;
 import org.terasology.launcher.log.TempLogFilePropertyDefiner;
 import org.terasology.launcher.util.BundleUtils;
+import org.terasology.launcher.util.HostServicesWrapper;
 import org.terasology.launcher.util.Languages;
 import org.terasology.launcher.util.LauncherStartFailedException;
 import org.terasology.launcher.version.TerasologyLauncherVersionInfo;
@@ -68,12 +69,32 @@ public final class TerasologyLauncher extends Application {
     private ProgressBar loadProgress;
     private Label progressText;
     private Stage mainStage;
-    private HostServices hostServices;
+    private HostServicesWrapper hostServices;
 
     public static void main(String[] args) {
         launch(args);
     }
 
+    /**
+     * Initialize the host service wrapper by attempting to use the JavaFX {@link HostServices}.
+     * @return the configured host service wrapper
+     */
+    private HostServicesWrapper initHostServices() {
+        HostServices hs;
+        try {
+            // This may throw an exception on a different thread, but we cannot catch it here o.O
+            // In addition, `hostServices` will be initialized, but disfunctional.
+            // Thus, we have no idea whether we can use the services or not...
+             hs = getHostServices();
+            // poor man's check: this will throw a NPE if the internal `hostServices.delegate` is not initialized
+            hs.getCodeBase();
+        } catch (NullPointerException e) {
+            logger.warn("Host Services not available - won't be able to open hyperlinks in the system browser.");
+            hs = null;
+        }
+        return new HostServicesWrapper(hs);
+    }
+
     @Override
     public void init() {
         ImageView splash = new ImageView(BundleUtils.getFxImage("splash"));
@@ -85,18 +106,7 @@ public void init() {
         progressText.setAlignment(Pos.CENTER);
         splashLayout.getStylesheets().add(BundleUtils.getStylesheet("css_splash"));
         splashLayout.setEffect(new DropShadow());
-
-        try {
-            // This may throw an exception on a different thread, but we cannot catch it here o.O
-            // In addition, `hostServices` will be initialized, but disfunctional.
-            // Thus, we have no idea whether we can use the services or not...
-            hostServices = getHostServices();
-            // poor man's check: this will throw a NPE if the internal `hostServices.deleagte` is not initialized
-            hostServices.getCodeBase();
-        } catch (NullPointerException e) {
-            logger.warn("Host Services not available - won't be able to open hyperlinks in the system browser.");
-            hostServices = null;
-        }
+        hostServices = initHostServices();
     }
 
     @Override

src/main/java/org/terasology/launcher/gui/javafx/ApplicationController.java

@@ -17,7 +17,6 @@
 package org.terasology.launcher.gui.javafx;
 
 import javafx.animation.Transition;
-import javafx.application.HostServices;
 import javafx.application.Platform;
 import javafx.beans.property.BooleanProperty;
 import javafx.beans.property.Property;
@@ -62,6 +61,7 @@
 import org.terasology.launcher.util.BundleUtils;
 import org.terasology.launcher.util.DownloadException;
 import org.terasology.launcher.util.GuiUtils;
+import org.terasology.launcher.util.HostServicesWrapper;
 import org.terasology.launcher.util.Languages;
 import org.terasology.launcher.util.ProgressListener;
 
@@ -376,7 +376,7 @@ protected void deleteAction() {
     }
 
     public void update(final Path newLauncherDirectory, final Path newDownloadDirectory, final Path newTempDirectory, final BaseLauncherSettings newLauncherSettings,
-                       final PackageManager newPackageManager, final Stage newStage, final HostServices hostServices) {
+                       final PackageManager newPackageManager, final Stage newStage, final HostServicesWrapper hostServices) {
         this.launcherDirectory = newLauncherDirectory;
         this.downloadDirectory = newDownloadDirectory;
         this.tempDirectory = newTempDirectory;

src/main/java/org/terasology/launcher/gui/javafx/FooterController.java

@@ -17,7 +17,6 @@
 package org.terasology.launcher.gui.javafx;
 
 import javafx.animation.Transition;
-import javafx.application.HostServices;
 import javafx.beans.property.Property;
 import javafx.beans.property.ReadOnlyProperty;
 import javafx.beans.property.SimpleObjectProperty;
@@ -30,9 +29,9 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.terasology.launcher.util.BundleUtils;
+import org.terasology.launcher.util.HostServicesWrapper;
 import org.terasology.launcher.version.TerasologyLauncherVersionInfo;
 
-import java.net.URI;
 import java.util.Optional;
 
 public class FooterController {
@@ -43,7 +42,7 @@ public class FooterController {
     private Button warningButton;
     @FXML
     private Label versionInfo;
-    private HostServices hostServices;
+    private HostServicesWrapper hostServices;
     private Property<Optional<Warning>> warningProperty;
 
     public FooterController() {
@@ -59,7 +58,7 @@ private void updateLabels() {
         }
     }
 
-    public void setHostServices(HostServices hostServices) {
+    public void setHostServices(HostServicesWrapper hostServices) {
         this.hostServices = hostServices;
     }
 
@@ -99,32 +98,32 @@ protected void handleSocialButtonMouseReleased(MouseEvent event) {
 
     @FXML
     protected void openFacebook() {
-        openUri(BundleUtils.getURI("terasology_facebook"));
+        hostServices.tryOpenUri(BundleUtils.getURI("terasology_facebook"));
     }
 
     @FXML
     protected void openGithub() {
-        openUri(BundleUtils.getURI("terasology_github"));
+        hostServices.tryOpenUri(BundleUtils.getURI("terasology_github"));
     }
 
     @FXML
     protected void openDiscord() {
-        openUri(BundleUtils.getURI("terasology_discord"));
+        hostServices.tryOpenUri(BundleUtils.getURI("terasology_discord"));
     }
 
     @FXML
     protected void openReddit() {
-        openUri(BundleUtils.getURI("terasology_reddit"));
+        hostServices.tryOpenUri(BundleUtils.getURI("terasology_reddit"));
     }
 
     @FXML
     protected void openTwitter() {
-        openUri(BundleUtils.getURI("terasology_twitter"));
+        hostServices.tryOpenUri(BundleUtils.getURI("terasology_twitter"));
     }
 
     @FXML
     protected void openYoutube() {
-        openUri(BundleUtils.getURI("terasology_youtube"));
+        hostServices.tryOpenUri(BundleUtils.getURI("terasology_youtube"));
     }
 
     @FXML
@@ -133,12 +132,6 @@ protected void openLogs() {
         //contentTabPane.getSelectionModel().select(2);
     }
 
-    private void openUri(URI uri) {
-        if (uri != null && hostServices != null) {
-            hostServices.showDocument(uri.toString());
-        }
-    }
-
     private void updateWarningButton(Optional<Warning> warning) {
         warningButton.setVisible(warning.isPresent());
         warning.ifPresent(w -> {

src/main/java/org/terasology/launcher/util/HostServicesWrapper.java

@@ -0,0 +1,70 @@
+package org.terasology.launcher.util;
+
+import javafx.application.HostServices;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.awt.Desktop;
+import java.io.IOException;
+import java.net.URI;
+
+/**
+ * Provide capabilities to interact with the hosting system (OS).
+ * <p>
+ * For instance, this allows to open a URL in the default browser on the system.
+ * <p>
+ * This abstraction is necessary as {@link javafx.application.HostServices} may not be available and we want to use
+ * {@link java.awt.Desktop} as a fallback solution.
+ */
+public class HostServicesWrapper {
+
+    private static final Logger logger = LoggerFactory.getLogger(HostServicesWrapper.class);
+
+    private final Desktop desktop;
+    private final HostServices hostServices;
+
+    /**
+     * Create a new {@link javafx.application.HostServices} wrapper.
+     * <p>
+     * If the given host service instance is {@code null}
+     *
+     * @param hostServices a JavaFX host services instance or null
+     */
+    public HostServicesWrapper(HostServices hostServices) {
+        this.hostServices = hostServices;
+
+        if (hostServices == null && Desktop.isDesktopSupported()) {
+            Desktop d = Desktop.getDesktop();
+            if (d.isSupported(Desktop.Action.BROWSE)) {
+                desktop = d;
+            } else {
+                desktop = null;
+            }
+        } else {
+            desktop = null;
+        }
+    }
+
+    /**
+     * Attempt to open the given URI with the default browser.
+     * <p>
+     * The preferred way to open the URI is via the {@link javafx.application.HostServices}, as a fallback
+     * {@link java.awt.Desktop} may be used internally.
+     * <p>
+     * In case the URI cannot be opened (e.g., because neither HostServices nor Desktop are available) this method will
+     * fail silently.
+     *
+     * @param uri the URI to open
+     */
+    public void tryOpenUri(URI uri) {
+        if (hostServices != null) {
+            hostServices.showDocument(uri.toString());
+        } else if (desktop != null) {
+            try {
+                desktop.browse(uri);
+            } catch (IOException e) {
+                logger.warn("Unable to open URI with 'Browse' action", e);
+            }
+        }
+    }
+}