/*
* Copyright 2011 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.ipc.invalidation.common;
/**
* Interface specifying a function to compute digests.
*
*/
public interface DigestFunction {
/** Clears the digest state. */
void reset();
/** Adds {@code data} to the digest being computed. */
void update(byte[] data);
/**
* Returns the digest of the data added by {@link #update}. After this call has been made,
* reset must be called before {@link #update} and {@link #getDigest} can be called.
*/
byte[] getDigest();
}