diff -r fd16c54261b3 -r 90ce3da70b43 jdk/test/java/nio/channels/FileChannel/MapReadOnly.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/nio/channels/FileChannel/MapReadOnly.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,50 @@
+/*
+ * Copyright 2001 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/* @test
+ * @bug 4510489
+ * @summary Verify IOUtil.java reads to buffer limits
+ */
+import java.io.*;
+import java.nio.*;
+import java.nio.channels.*;
+
+public class MapReadOnly {
+    public static void main (String args[]) throws Exception {
+        File testFile = File.createTempFile("test2", null);
+        testFile.deleteOnExit();
+        RandomAccessFile raf = new RandomAccessFile(testFile, "rw");
+        FileChannel fc = raf.getChannel();
+        MappedByteBuffer mbb = fc.map(FileChannel.MapMode.READ_ONLY, 0L,
+                                      (int) fc.size());
+        mbb.load();
+        try {
+            mbb.put((byte)3);
+            throw new Exception("Test failed");
+        } catch (ReadOnlyBufferException robe) {
+            // Correct result
+        }
+        fc.close();
+        raf.close();
+    }
+}