| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 org.apache.hadoop.hbase.io.hfile; |
| |
| import java.util.Random; |
| import org.apache.hadoop.hbase.util.RandomDistribution.DiscreteRNG; |
| import org.apache.hadoop.io.BytesWritable; |
| |
| /* |
| * <p> |
| * Copied from |
| * <a href="https://issues.apache.org/jira/browse/HADOOP-3315">hadoop-3315 tfile</a>. |
| * Remove after tfile is committed and use the tfile version of this class |
| * instead.</p> |
| */ |
| class KeySampler { |
| Random random; |
| int min, max; |
| DiscreteRNG keyLenRNG; |
| private static final int MIN_KEY_LEN = 4; |
| |
| public KeySampler(Random random, byte[] first, byte[] last, DiscreteRNG keyLenRNG) { |
| this.random = random; |
| int firstLen = keyPrefixToInt(first); |
| int lastLen = keyPrefixToInt(last); |
| min = Math.min(firstLen, lastLen); |
| max = Math.max(firstLen, lastLen); |
| System.out.println(min); |
| System.out.println(max); |
| this.keyLenRNG = keyLenRNG; |
| } |
| |
| private int keyPrefixToInt(byte[] key) { |
| byte[] b = key; |
| int o = 0; |
| return (b[o] & 0xff) << 24 | (b[o + 1] & 0xff) << 16 | (b[o + 2] & 0xff) << 8 |
| | (b[o + 3] & 0xff); |
| } |
| |
| public void next(BytesWritable key) { |
| key.setSize(Math.max(MIN_KEY_LEN, keyLenRNG.nextInt())); |
| random.nextBytes(key.get()); |
| int rnd = 0; |
| if (max != min) { |
| rnd = random.nextInt(max - min); |
| } |
| int n = rnd + min; |
| byte[] b = key.get(); |
| b[0] = (byte) (n >> 24); |
| b[1] = (byte) (n >> 16); |
| b[2] = (byte) (n >> 8); |
| b[3] = (byte) n; |
| } |
| } |