8259687: JTabbedPane.setComponentAt doesn't hide previously visible tab component

Reviewed-by: psadhukhan, dnguyen

Author: Harshitha Onkar

src/java.desktop/share/classes/javax/swing/JTabbedPane.java

@@ -1598,6 +1598,11 @@ public void setComponentAt(int index, Component component) {
             boolean selectedPage = (getSelectedIndex() == index);
 
             if (selectedPage) {
+                if (this.visComp != null && this.visComp.isVisible()
+                        && !this.visComp.equals(component)) {
+                    // previous component visibility is set to false
+                    this.visComp.setVisible(false);
+                }
                 this.visComp = component;
             }
 

test/jdk/javax/swing/JTabbedPane/TabbedPaneBug.java

@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+import java.awt.AWTException;
+import java.awt.Color;
+import java.awt.Robot;
+import java.lang.reflect.InvocationTargetException;
+import javax.swing.JFrame;
+import javax.swing.JPanel;
+import javax.swing.JTabbedPane;
+import javax.swing.SwingUtilities;
+
+/*
+ * @test
+ * @bug 8259687
+ * @key headful
+ * @summary Tests whether the selected tab's component is on the top and visible.
+ * @run main TabbedPaneBug
+ */
+public class TabbedPaneBug {
+
+    private static final int FIRST = 0;
+    private static final int SECOND = 1;
+    private static JFrame window;
+    private static JTabbedPane tabs;
+    private static final JPanel firstTab = new JPanel();
+    private static final JPanel secondTab = new JPanel();
+
+    public static void main(String[] args) throws AWTException,
+            InterruptedException, InvocationTargetException {
+        try {
+            Robot robot = new Robot();
+            robot.setAutoDelay(200);
+            SwingUtilities.invokeAndWait(() -> createAndShowGUI());
+
+            robot.waitForIdle();
+            robot.mouseMove(window.getWidth()/2, window.getHeight()/2);
+            robot.delay(500);
+            Color actualColor = robot.getPixelColor(window.getWidth()/2,
+                    window.getHeight()/2);
+            robot.delay(200);
+
+            if (actualColor.equals(Color.RED)) {
+                throw new RuntimeException("The second (selected) component" +
+                        " is not on the top!!");
+            }
+        } finally {
+            SwingUtilities.invokeAndWait(() -> {
+                if (window != null) {
+                    window.dispose();
+                }
+            });
+        }
+
+    }
+
+    private static void createAndShowGUI() {
+        window = new JFrame("Tabbed Pane Bug");
+        tabs = new JTabbedPane();
+
+        firstTab.setBackground(Color.RED);
+        secondTab.setBackground(Color.GREEN);
+
+        tabs.addChangeListener((e) -> {
+            if (tabs.getSelectedComponent() == null) {
+                switch (tabs.getSelectedIndex()) {
+                    case FIRST:
+                        tabs.setComponentAt(tabs.getSelectedIndex(), firstTab);
+                        break;
+                    case SECOND:
+                        tabs.setComponentAt(tabs.getSelectedIndex(), secondTab);
+                        break;
+                    default:
+                }
+            }
+        });
+
+        tabs.addTab("First", null);
+        tabs.addTab("Second", null);
+
+        tabs.setSelectedIndex(SECOND);
+        window.add(tabs);
+        window.setSize(200, 200);
+        window.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
+        window.setVisible(true);
+    }
+}