Update JDatePicker and fix DateWidget not adapting dark theme

JDatePicker 2.0.2 is compiled for java 17 and won't work for Java 8.

Therefore, this commit updates the minimum Java version to 17,
and fixes backwards-incompatible behavior of the OpenJDK 17 compiler.

Co-Authored-By: Curtis Rueden <ctrueden@wisc.edu>

Author: tferr

.github/workflows/build.yml

@@ -19,7 +19,7 @@ jobs:
       - name: Set up Java
         uses: actions/setup-java@v5
         with:
-          java-version: '8'
+          java-version: '17'
           distribution: 'zulu'
           cache: 'maven'
       - name: Set up CI environment

pom.xml

@@ -102,7 +102,7 @@
 	</ciManagement>
 
 	<properties>
-		<scijava.jvm.version>8</scijava.jvm.version>
+		<scijava.jvm.version>17</scijava.jvm.version>
 		<package-name>org.scijava.ui.swing</package-name>
 		<license.licenseName>bsd_2</license.licenseName>
 		<license.copyrightOwners>SciJava developers.</license.copyrightOwners>
@@ -111,7 +111,7 @@
 		<!-- NB: Deploy releases to the SciJava Maven repository. -->
 		<releaseProfiles>sign,deploy-to-scijava</releaseProfiles>
 
-		<jdatepicker.version>1.3.2</jdatepicker.version>
+		<jdatepicker.version>2.0.1</jdatepicker.version>
 		<object-inspector.version>0.1</object-inspector.version>
 
 		<!-- TEMP: for Task#log(); drop once propagated to pom-scijava. -->
@@ -171,7 +171,7 @@
 			<version>${object-inspector.version}</version>
 		</dependency>
 		<dependency>
-			<groupId>net.sourceforge.jdatepicker</groupId>
+			<groupId>org.jdatepicker</groupId>
 			<artifactId>jdatepicker</artifactId>
 			<version>${jdatepicker.version}</version>
 		</dependency>

src/main/java/org/scijava/ui/swing/commands/WatchEventsFrame.java

@@ -397,7 +397,8 @@ private Iterable<DefaultMutableTreeNode> children(
 		final DefaultMutableTreeNode node)
 	{
 		@SuppressWarnings("unchecked")
-		final Enumeration<DefaultMutableTreeNode> en = node.children();
+		final Enumeration<DefaultMutableTreeNode> en =
+			(Enumeration<DefaultMutableTreeNode>) (Enumeration<?>) node.children();
 		return new IteratorPlus<>(en);
 	}
 

src/main/java/org/scijava/ui/swing/widget/SwingDateWidget.java

@@ -29,15 +29,18 @@
 
 package org.scijava.ui.swing.widget;
 
+import java.awt.Color;
 import java.awt.event.ActionEvent;
 import java.awt.event.ActionListener;
 import java.util.Date;
 
 import javax.swing.JPanel;
+import javax.swing.UIManager;
 
-import net.sourceforge.jdatepicker.impl.JDatePanelImpl;
-import net.sourceforge.jdatepicker.impl.JDatePickerImpl;
-import net.sourceforge.jdatepicker.impl.UtilDateModel;
+import org.jdatepicker.ComponentColorDefaults;
+import org.jdatepicker.ComponentColorDefaults.Key;
+import org.jdatepicker.JDatePicker;
+import org.jdatepicker.UtilDateModel;
 
 import org.scijava.log.LogService;
 import org.scijava.plugin.Parameter;
@@ -75,15 +78,49 @@ public void set(final WidgetModel model) {
 		super.set(model);
 
 		dateModel = new UtilDateModel();
-		final JDatePickerImpl datePicker =
-			new JDatePickerImpl(new JDatePanelImpl(dateModel), null);
+		applyThemeColors();
+		// NB: the picker must be built on our model, or user picks never reach it
+		final JDatePicker datePicker = new JDatePicker(dateModel);
 		setToolTip(datePicker);
 		getComponent().add(datePicker);
 		datePicker.addActionListener(this);
 
 		refreshWidget();
 	}
 
+	// -- Helper methods --
+
+	/**
+	 * Maps the picker colors to the current look and feel. Note that
+	 * {@link ComponentColorDefaults} is a global singleton read when a picker
+	 * is created, so existing pickers keep their colors on a theme change
+	 */
+	private static void applyThemeColors() {
+		setColor(Key.BG_MONTH_SELECTOR, "TableHeader.background");
+		setColor(Key.FG_MONTH_SELECTOR, "TableHeader.foreground");
+		setColor(Key.BG_GRID_HEADER, "TableHeader.background");
+		setColor(Key.FG_GRID_HEADER, "TableHeader.foreground");
+		setColor(Key.BG_GRID, "Table.background");
+		setColor(Key.BG_GRID_NOT_SELECTABLE, "Panel.background");
+		setColor(Key.FG_GRID_THIS_MONTH, "Table.foreground");
+		setColor(Key.FG_GRID_OTHER_MONTH, "Label.disabledForeground");
+		setColor(Key.FG_GRID_TODAY, "Component.accentColor");
+		setColor(Key.FG_GRID_SELECTED, "Table.selectionForeground");
+		setColor(Key.BG_GRID_SELECTED, "Table.selectionBackground");
+		setColor(Key.FG_GRID_TODAY_SELECTED, "Table.selectionForeground");
+		setColor(Key.BG_GRID_TODAY_SELECTED, "Table.selectionBackground");
+		setColor(Key.BG_TODAY_SELECTOR, "Panel.background");
+		setColor(Key.FG_TODAY_SELECTOR_ENABLED, "Label.foreground");
+		setColor(Key.FG_TODAY_SELECTOR_DISABLED, "Label.disabledForeground");
+		setColor(Key.POPUP_BORDER, "Component.borderColor");
+	}
+
+	/** Sets a picker color from a UIManager key, if the key is defined */
+	private static void setColor(final Key key, final String uiKey) {
+		final Color color = UIManager.getColor(uiKey);
+		if (color != null) ComponentColorDefaults.getInstance().setColor(key, color);
+	}
+
 	// -- Typed methods --
 
 	@Override