001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase.util;
019
020import org.apache.yetus.audience.InterfaceAudience;
021
022/**
023 * Used to calculate the hash {@link Hash} algorithms for Bloomfilters.
024 *
025 * @param <T> the type of HashKey
026 */
027@InterfaceAudience.Private
028public abstract class HashKey<T> {
029  protected final T t;
030
031  public HashKey(T t) {
032    this.t = t;
033  }
034
035  /**
036   * @param pos
037   * @return The byte at the given position in this HashKey
038   */
039  public abstract byte get(int pos);
040
041  /**
042   * @return The number of bytes in this HashKey
043   */
044  public abstract int length();
045}