--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.max.base/src/com/sun/max/io/SeekableByteArrayOutputStream.java	Sat Dec 17 19:59:18 2011 +0100
@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2007, 2011, 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.
+ */
+package com.sun.max.io;
+
+import java.io.*;
+
+/**
+ * A {@link ByteArrayOutputStream} that can have its write position {@linkplain #seek(int) updated}.
+ */
+public class SeekableByteArrayOutputStream extends ByteArrayOutputStream {
+
+    private int highestCount;
+
+    /**
+     * @see ByteArrayOutputStream#ByteArrayOutputStream()
+     */
+    public SeekableByteArrayOutputStream() {
+    }
+
+    /**
+     * @see ByteArrayOutputStream#ByteArrayOutputStream(int)
+     */
+    public SeekableByteArrayOutputStream(int size) {
+        super(size);
+    }
+
+    /**
+     * Updates the write position of this stream. The stream can only be repositioned between 0 and the
+     * {@linkplain #endOfStream() end of the stream}.
+     * 
+     * @param index
+     *            the index to which the write position of this stream will be set
+     * @throws IllegalArgumentException
+     *             if {@code index > highestSeekIndex()}
+     */
+    public void seek(int index) throws IllegalArgumentException {
+        if (endOfStream() < index) {
+            throw new IllegalArgumentException();
+        }
+        count = index;
+    }
+
+    /**
+     * Gets the index one past the highest index that has been written to in this stream.
+     */
+    public int endOfStream() {
+        if (highestCount < count) {
+            highestCount = count;
+        }
+        return highestCount;
+    }
+
+    @Override
+    public void reset() {
+        super.reset();
+        highestCount = 0;
+    }
+
+    /**
+     * Copies the {@code length} bytes of this byte array output stream starting at {@code offset} to {@code buf}
+     * starting at {@code bufOffset}.
+     */
+    public void copyTo(int offset, byte[] toBuffer, int toOffset, int length) {
+        System.arraycopy(this.buf, offset, toBuffer, toOffset, length);
+    }
+}