001 /** 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017 018 package org.apache.geronimo.util.crypto; 019 020 /** 021 * interface that a message digest conforms to. 022 */ 023 public interface Digest 024 { 025 /** 026 * return the algorithm name 027 * 028 * @return the algorithm name 029 */ 030 public String getAlgorithmName(); 031 032 /** 033 * return the size, in bytes, of the digest produced by this message digest. 034 * 035 * @return the size, in bytes, of the digest produced by this message digest. 036 */ 037 public int getDigestSize(); 038 039 /** 040 * update the message digest with a single byte. 041 * 042 * @param in the input byte to be entered. 043 */ 044 public void update(byte in); 045 046 /** 047 * update the message digest with a block of bytes. 048 * 049 * @param in the byte array containing the data. 050 * @param inOff the offset into the byte array where the data starts. 051 * @param len the length of the data. 052 */ 053 public void update(byte[] in, int inOff, int len); 054 055 /** 056 * close the digest, producing the final digest value. The doFinal 057 * call leaves the digest reset. 058 * 059 * @param out the array the digest is to be copied into. 060 * @param outOff the offset into the out array the digest is to start at. 061 */ 062 public int doFinal(byte[] out, int outOff); 063 064 /** 065 * reset the digest back to it's initial state. 066 */ 067 public void reset(); 068 }