--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/util/zip/CRC32.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,90 @@
+/*
+ * Copyright 1996-2005 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.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun 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 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.
+ */
+
+package java.util.zip;
+
+/**
+ * A class that can be used to compute the CRC-32 of a data stream.
+ *
+ * @see         Checksum
+ * @author      David Connelly
+ */
+public
+class CRC32 implements Checksum {
+    private int crc;
+
+    /**
+     * Creates a new CRC32 object.
+     */
+    public CRC32() {
+    }
+
+
+    /**
+     * Updates CRC-32 with specified byte.
+     */
+    public void update(int b) {
+        crc = update(crc, b);
+    }
+
+    /**
+     * Updates CRC-32 with specified array of bytes.
+     */
+    public void update(byte[] b, int off, int len) {
+        if (b == null) {
+            throw new NullPointerException();
+        }
+        if (off < 0 || len < 0 || off > b.length - len) {
+            throw new ArrayIndexOutOfBoundsException();
+        }
+        crc = updateBytes(crc, b, off, len);
+    }
+
+    /**
+     * Updates checksum with specified array of bytes.
+     *
+     * @param b the array of bytes to update the checksum with
+     */
+    public void update(byte[] b) {
+        crc = updateBytes(crc, b, 0, b.length);
+    }
+
+    /**
+     * Resets CRC-32 to initial value.
+     */
+    public void reset() {
+        crc = 0;
+    }
+
+    /**
+     * Returns CRC-32 value.
+     */
+    public long getValue() {
+        return (long)crc & 0xffffffffL;
+    }
+
+    private native static int update(int crc, int b);
+    private native static int updateBytes(int crc, byte[] b, int off, int len);
+}