Adds regression test.

Adds a regression for DK-8293776 : Adds CSS 4 and 8 digits hex coded Color #13

Author: scientificware

test/jdk/javax/swing/text/html/CSS/Hex3468DigitsColor.java

@@ -0,0 +1,93 @@
+/*
+ * 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 8293776
+ * @summary Adds CSS 4 and 8 digits hex coded Color
+ * @run main Hex3468DigitsColor
+ * @author Guy Abossolo Foh - ScientificWare
+ */
+
+import java.awt.Color;
+import javax.swing.text.html.StyleSheet;
+
+public class Hex3468DigitsColor {
+
+    public static void main(String[] args) {
+        StringBuilder result = new StringBuilder();
+        boolean passed = true;
+        StyleSheet styleSheet = new StyleSheet();
+        // #rgba Should be interpreted as #rrggbbaa according CSS Color Level 4.
+        // Then expecting r=255 g=17 b=34 a=170
+        Color color = styleSheet.stringToColor("#f12a");
+        int red = color.getRed();
+        int green = color.getGreen();
+        int blue = color.getBlue();
+        int alpha = color.getAlpha();
+        result.append("  Test for #f00a");
+        if (red != 255) {
+            result.append(", expected r=255 but r=%s found".formatted(red));
+            passed = false;
+        }
+        if (green != 17) {
+            result.append(", expected g=17 but g=%s found".formatted(green));
+            passed = false;
+        }
+        if (blue != 34) {
+            result.append(", expected b=34 but b=%s found".formatted(blue));
+            passed = false;
+        }
+        if (alpha != 170) {
+            result.append(", expected a=170 but a=%s found".formatted(alpha));
+            passed = false;
+        }
+        // In #rrggbbaa last two digits should be interpreted as Alpha value according CSS Color Level 4.
+        // Then expecting r=255 g=17 b=34 a=170
+        color = styleSheet.stringToColor("#ff1122aa");
+        alpha = color.getAlpha();
+        result.append("\n  Test for #ff1122aa");
+        if (red != 255) {
+            result.append(", expected r=255 but r=%s found".formatted(red));
+            passed = false;
+        }
+        if (green != 17) {
+            result.append(", expected g=17 but g=%s found".formatted(green));
+            passed = false;
+        }
+        if (blue != 34) {
+            result.append(", expected b=34 but b=%s found".formatted(blue));
+            passed = false;
+        }
+        if (alpha != 170) {
+            result.append(", expected a=170 but a=%s found".formatted(alpha));
+            passed = false;
+        }
+        if (!passed) {
+            result.insert(0, "Failed :");
+            throw new RuntimeException(result.toString());
+        }
+    }
+}