--- /dev/null	2015-07-25 15:02:20.097409468 -0700
+++ new/test/java/lang/String/CompactString/RegionMatches.java	2015-10-30 14:04:16.938208874 -0700
@@ -0,0 +1,105 @@
+/*
+ * Copyright (c) 2015, 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 org.testng.annotations.DataProvider;
+import org.testng.annotations.Test;
+
+import static org.testng.Assert.assertEquals;
+
+/*
+ * @test
+ * @bug 8077559
+ * @summary Tests Compact String. This one is for String.regionMatches.
+ * @run testng/othervm -XX:+CompactStrings RegionMatches
+ * @run testng/othervm -XX:-CompactStrings RegionMatches
+ */
+
+public class RegionMatches extends CompactString {
+
+    @DataProvider
+    public Object[][] provider() {
+        return new Object[][] {
+
+                new Object[] { STRING_EMPTY, true, 0, "", 0, 0, true },
+                new Object[] { STRING_EMPTY, true, 0, "", 0, 1, false },
+                new Object[] { STRING_EMPTY, true, 0, "A", 0, 0, true },
+                new Object[] { STRING_EMPTY, true, 0, "", 0, 0, true },
+                new Object[] { STRING_EMPTY, true, 0, "", 0, 1, false },
+                new Object[] { STRING_L1, false, 0, "a", 0, 1, false },
+                new Object[] { STRING_L1, false, 0, "BA", 1, 1, true },
+                new Object[] { STRING_L1, false, 0, "Ba", 1, 1, false },
+                new Object[] { STRING_L1, true, 0, "a", 0, 1, true },
+                new Object[] { STRING_L1, true, 0, "BA", 1, 1, true },
+                new Object[] { STRING_L1, true, 0, "Ba", 1, 1, true },
+                new Object[] { STRING_L2, true, 1, "b", 0, 1, true },
+                new Object[] { STRING_L2, true, 1, "B", 0, 1, true },
+                new Object[] { STRING_L2, true, 0, "xaBc", 1, 2, true },
+                new Object[] { STRING_L2, false, 0, "AB", 0, 2, true },
+                new Object[] { STRING_L2, false, 0, "Ab", 0, 2, false },
+                new Object[] { STRING_L2, false, 1, "BAB", 2, 1, true },
+                new Object[] { STRING_LLONG, true, 1, "bCdEF", 0, 5, true },
+                new Object[] { STRING_LLONG, false, 2, "CDEFG", 0, 5, true },
+                new Object[] { STRING_LLONG, true, 2, "CDEFg", 0, 5, true },
+                new Object[] { STRING_U1, true, 0, "\uFF41", 0, 1, true },
+                new Object[] { STRING_U1, false, 0, "\uFF41", 0, 1, false },
+                new Object[] { STRING_MDUPLICATE1, true, 0, "\uFF41a\uFF41", 0,
+                        3, true },
+                new Object[] { STRING_MDUPLICATE1, false, 0, "\uFF21a\uFF21",
+                        0, 3, false },
+                new Object[] { STRING_SUPPLEMENTARY, true, 1, "\uDC00\uD801",
+                        0, 2, true },
+                new Object[] { STRING_SUPPLEMENTARY, true, 4, "\uFF21", 0, 1,
+                        true },
+                new Object[] { STRING_SUPPLEMENTARY, true, 5, "A", 0, 1, true },
+                new Object[] { STRING_SUPPLEMENTARY_LOWERCASE, false, 0,
+                        "\uD801\uDC28\uD801\uDC29", 0, 4, true },
+                new Object[] { STRING_SUPPLEMENTARY_LOWERCASE, true, 1,
+                        "\uDC28\uD801", 0, 2, true },
+                new Object[] { STRING_SUPPLEMENTARY_LOWERCASE, true, 1,
+                        "\uDC00\uD801", 0, 2, false },
+                new Object[] { STRING_SUPPLEMENTARY_LOWERCASE, true, 4,
+                        "\uFF21", 0, 1, true },
+                new Object[] { STRING_SUPPLEMENTARY_LOWERCASE, false, 4,
+                        "\uFF21", 0, 1, false },
+                new Object[] { STRING_SUPPLEMENTARY_LOWERCASE, false, 4,
+                        "\uFF41", 0, 1, true }, };
+    }
+
+    @Test(dataProvider = "provider")
+    public void testRegionMatches(String str, boolean ignoreCase, int toffset,
+            String other, int ooffset, int len, boolean expected) {
+        map.get(str)
+                .forEach(
+                        (source, data) -> {
+                            assertEquals(
+                                    data.regionMatches(ignoreCase, toffset,
+                                            other, ooffset, len),
+                                    expected,
+                                    String.format(
+                                            "testing String(%s).regionMatches(%b, %d, %s, %d, %d), source : %s, ",
+                                            escapeNonASCIIs(data), ignoreCase,
+                                            toffset, escapeNonASCIIs(other),
+                                            ooffset, len, source));
+                        });
+    }
+}