8256019: JLabel HTML text does not support translucent text colors

Reviewed-by: serb

src/java.desktop/share/classes/javax/swing/text/html/CSS.java

@@ -1387,7 +1387,7 @@ public class CSS implements Serializable {
 
     /**
      * Convert a color string such as "RED" or "#NNNNNN" or "rgb(r, g, b)"
-     * to a Color.
+     * or "rgba(r, g, b, a)" to a Color.
      */
     static Color stringToColor(String str) {
       Color color;
@@ -1399,6 +1399,8 @@ public class CSS implements Serializable {
         color = Color.black;
       else if (str.startsWith("rgb(")) {
           color = parseRGB(str);
+      } else if (str.startsWith("rgba(")) {
+          color = parseRGBA(str);
       }
       else if (str.charAt(0) == '#')
         color = hexToColor(str);
@@ -1452,20 +1454,33 @@ public class CSS implements Serializable {
         int[] index = new int[1];
 
         index[0] = 4;
-        int red = getColorComponent(string, index);
-        int green = getColorComponent(string, index);
-        int blue = getColorComponent(string, index);
+        int red = (int)getColorComponent(string, index);
+        int green = (int)getColorComponent(string, index);
+        int blue = (int)getColorComponent(string, index);
 
         return new Color(red, green, blue);
     }
 
+    private static Color parseRGBA(String string) {
+        // Find the next numeric char
+        int[] index = new int[1];
+
+        index[0] = 4;
+        float red = getColorComponent(string, index)/255f;
+        float green = getColorComponent(string, index)/255f;
+        float blue = getColorComponent(string, index)/255f;
+        float alpha = getColorComponent(string, index);
+
+        return new Color(red, green, blue, alpha);
+    }
+
     /**
      * Returns the next integer value from <code>string</code> starting
      * at <code>index[0]</code>. The value can either can an integer, or
      * a percentage (floating number ending with %), in which case it is
      * multiplied by 255.
      */
-    private static int getColorComponent(String string, int[] index) {
+    private static float getColorComponent(String string, int[] index) {
         int length = string.length();
         char aChar;
 
@@ -1501,7 +1516,7 @@ public class CSS implements Serializable {
                     index[0]++;
                     value = value * 255f / 100f;
                 }
-                return Math.min(255, Math.max(0, (int)value));
+                return Math.min(255f, Math.max(0, value));
             } catch (NumberFormatException nfe) {
                 // Treat as 0
             }

test/jdk/javax/swing/JLabel/TestTranslucentLabelText.java

@@ -0,0 +1,175 @@
+/*
+ * Copyright (c) 2020, 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.
+ */
+/*
+ * @test
+ * @bug 8256019
+ * @summary Verifies if JLabel HTML text support translucent text colors
+ * @run main/manual TestTranslucentLabelText
+ */
+
+import java.awt.BorderLayout;
+import java.awt.Color;
+import java.awt.Dimension;
+import java.awt.Font;
+import java.awt.FlowLayout;
+import java.awt.event.WindowAdapter;
+import java.awt.event.WindowEvent;
+import java.util.concurrent.CountDownLatch;
+import javax.imageio.ImageIO;
+import javax.swing.JFrame;
+import javax.swing.JDialog;
+import javax.swing.JTextArea;
+import javax.swing.JButton;
+import javax.swing.JPanel;
+import javax.swing.JLabel;
+import javax.swing.SwingUtilities;
+
+public class TestTranslucentLabelText {
+    private static Color background = new Color(0, 150, 0);
+    private static Color foreground = new Color(255, 255, 255, 120);
+    private static Font font = new Font("Sans Serif", Font.PLAIN, 24);
+    private static JFrame frame;
+    static boolean testResult;
+    static CountDownLatch latch;
+    private static Thread mainThread;
+    private static boolean testPassed;
+    private static boolean testGeneratedInterrupt;
+
+    private static void doTest(Runnable action) {
+        String description
+                = " A frame with 2 labels will be shown in middle of screen.\n"
+                + " Left side label text should be opaque.\n "
+                + " Right side label text should be translucent.\n"
+                + " If Right side label text is translucent, press PASS else press FAIL";
+
+        final JDialog dialog = new JDialog();
+        dialog.setTitle("JLabelTranslucentTest");
+        JTextArea textArea = new JTextArea(description);
+        textArea.setEditable(false);
+        final JButton testButton = new JButton("Start Test");
+        final JButton passButton = new JButton("PASS");
+        passButton.setEnabled(false);
+        passButton.addActionListener((e) -> {
+            dialog.dispose();
+            frame.dispose();
+            pass();
+        });
+        final JButton failButton = new JButton("FAIL");
+        failButton.setEnabled(false);
+        failButton.addActionListener((e) -> {
+            dialog.dispose();
+            frame.dispose();
+            fail();
+        });
+        testButton.addActionListener((e) -> {
+            testButton.setEnabled(false);
+            action.run();
+            passButton.setEnabled(true);
+            failButton.setEnabled(true);
+        });
+        JPanel mainPanel = new JPanel(new BorderLayout());
+        mainPanel.add(textArea, BorderLayout.CENTER);
+        JPanel buttonPanel = new JPanel(new FlowLayout());
+        buttonPanel.add(testButton);
+        buttonPanel.add(passButton);
+        buttonPanel.add(failButton);
+        mainPanel.add(buttonPanel, BorderLayout.SOUTH);
+        dialog.add(mainPanel);
+        dialog.pack();
+        dialog.setVisible(true);
+        dialog.addWindowListener(new WindowAdapter() {
+            @Override
+            public void windowClosing(WindowEvent e) {
+                System.out.println("main dialog closing");
+                testGeneratedInterrupt = false;
+                frame.dispose();
+                mainThread.interrupt();
+            }
+        });
+    }
+
+    public static synchronized void pass() {
+        testPassed = true;
+        testGeneratedInterrupt = true;
+        mainThread.interrupt();
+    }
+
+    public static synchronized void fail() {
+        testPassed = false;
+        testGeneratedInterrupt = true;
+        mainThread.interrupt();
+    }
+
+
+    private static JLabel create(String text)
+    {
+        JLabel label = new JLabel(text);
+        label.setOpaque(true);
+        label.setBackground(background);
+        label.setForeground(foreground);
+        label.setFont(font);
+        label.setPreferredSize(new Dimension(200, 40));
+        frame.add(label);
+
+        return label;
+    }
+
+    private static void runTest() {
+        frame = new JFrame();
+        frame.setUndecorated(true);
+        frame.setLayout(new FlowLayout());
+
+        //JLabel l1 = create("Test1");
+        //JLabel opqLabel = create("<html>Test2</html>");
+        JLabel opqLabel = create("<html><p style=\"color:rgba(255, 0, 0, 1.00)\">TestLabel</p></html>");
+        JLabel tranLabel = create("<html><p style=\"color:rgba(255, 0, 0, 0.5)\">TestLabel</p></html>");
+
+        frame.pack();
+
+        frame.setLocationRelativeTo(null);
+        frame.setVisible(true);
+        frame.toFront();
+    }
+
+    public static void main(String[] args) throws Exception {
+        SwingUtilities.invokeAndWait(() -> {
+            doTest(TestTranslucentLabelText::runTest);
+        });
+        mainThread = Thread.currentThread();
+        try {
+            Thread.sleep(180000);
+        } catch (InterruptedException e) {
+            if (!testPassed && testGeneratedInterrupt) {
+                throw new RuntimeException("" +
+                   "Label HTML text does not support translucent text colors");
+            }
+        }
+        if (!testGeneratedInterrupt) {
+            throw new RuntimeException("user has not executed the test");
+        }
+
+    }
+
+
+}
+