| /* Checksum.java - Interface to compute a data checksum |
| Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| package java.util.zip; |
| |
| /* |
| * Written using on-line Java Platform 1.2 API Specification, as well |
| * as "The Java Class Libraries", 2nd edition (Addison-Wesley, 1998). |
| * Status: Believed complete and correct. |
| */ |
| |
| /** |
| * Interface to compute a data checksum used by checked input/output streams. |
| * A data checksum can be updated by one byte or with a byte array. After each |
| * update the value of the current checksum can be returned by calling |
| * <code>getValue</code>. The complete checksum object can also be reset |
| * so it can be used again with new data. |
| * |
| * @see CheckedInputStream |
| * @see CheckedOutputStream |
| * |
| * @author Per Bothner |
| * @author Jochen Hoenicke |
| */ |
| public interface Checksum |
| { |
| /** |
| * Returns the data checksum computed so far. |
| */ |
| long getValue(); |
| |
| /** |
| * Resets the data checksum as if no update was ever called. |
| */ |
| void reset(); |
| |
| /** |
| * Adds one byte to the data checksum. |
| * |
| * @param bval the data value to add. The high byte of the int is ignored. |
| */ |
| void update (int bval); |
| |
| /** |
| * Adds the byte array to the data checksum. |
| * |
| * @param buf the buffer which contains the data |
| * @param off the offset in the buffer where the data starts |
| * @param len the length of the data |
| */ |
| void update (byte[] buf, int off, int len); |
| } |