--- /dev/null	2015-07-25 15:02:20.097409468 -0700
+++ new/test/java/lang/String/CompactString/CompareTo.java	2015-10-30 14:04:08.500240827 -0700
@@ -0,0 +1,94 @@
+/*
+ * 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.compareTo.
+ * @run testng/othervm -XX:+CompactStrings CompareTo
+ * @run testng/othervm -XX:-CompactStrings CompareTo
+ */
+
+public class CompareTo extends CompactString {
+
+    @DataProvider
+    public Object[][] provider() {
+        return new Object[][] {
+
+        new Object[] { STRING_EMPTY, "A", -1 },
+                new Object[] { STRING_EMPTY, "\uFF21", -1 },
+                new Object[] { STRING_L1, "AB", -1 },
+                new Object[] { STRING_L1, "A", 0 },
+                new Object[] { STRING_L1, "a", -32 },
+                new Object[] { STRING_L1, "\uFF21", -65248 },
+                new Object[] { STRING_L2, "AB", 0 },
+                new Object[] { STRING_L2, "Ab", -32 },
+                new Object[] { STRING_L2, "AA", 1 },
+                new Object[] { STRING_L2, "\uFF21", -65248 },
+                new Object[] { STRING_L2, "A\uFF21", -65247 },
+                new Object[] { STRING_L4, "ABC", 1 },
+                new Object[] { STRING_L4, "AB", 2 },
+                new Object[] { STRING_L4, "ABcD", -32 },
+                new Object[] { STRING_L4, "ABCD\uFF21\uFF21", -2 },
+                new Object[] { STRING_L4, "ABCD\uFF21", -1 },
+                new Object[] { STRING_LLONG, "ABCDEFG\uFF21", -65241 },
+                new Object[] { STRING_LLONG, "AB", 6 },
+                new Object[] { STRING_LLONG, "ABCD", 4 },
+                new Object[] { STRING_LLONG, "ABCDEFGH\uFF21\uFF21", -2 },
+                new Object[] { STRING_U1, "\uFF21", 0 },
+                new Object[] { STRING_U1, "\uFF22", -1 },
+                new Object[] { STRING_U1, "\uFF21\uFF22", -1 },
+                new Object[] { STRING_U1, "A", 65248 },
+                new Object[] { STRING_U2, "\uFF21\uFF22", 0 },
+                new Object[] { STRING_U2, "\uFF22", -1 },
+                new Object[] { STRING_U2, "\uFF21\uFF21", 1 },
+                new Object[] { STRING_U2, "A", 65248 },
+                new Object[] { STRING_M12, "\uFF21A", 0 },
+                new Object[] { STRING_M12, "A\uFF21", 65248 },
+                new Object[] { STRING_M12, "\uFF21\uFF21", -65248 },
+                new Object[] { STRING_M11, "A\uFF21", 0 },
+                new Object[] { STRING_M11, "\uFF21A", -65248 },
+                new Object[] { STRING_M11, "AA", 65248 }, };
+    }
+
+    @Test(dataProvider = "provider")
+    public void testCompareTo(String str, String anotherString, int expected) {
+        map.get(str)
+                .forEach(
+                        (source, data) -> {
+                            assertEquals(
+                                    data.compareTo(anotherString),
+                                    expected,
+                                    String.format(
+                                            "testing String(%s).compareTo(%s), source : %s, ",
+                                            escapeNonASCIIs(data),
+                                            escapeNonASCIIs(anotherString),
+                                            source));
+                        });
+    }
+}