ceph/src/rocksdb/java/jmh/src/main/java/org/rocksdb/util/KVUtils.java

   1 /**
   2  * Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
   3  *  This source code is licensed under both the GPLv2 (found in the
   4  *  COPYING file in the root directory) and Apache 2.0 License
   5  *  (found in the LICENSE.Apache file in the root directory).
   6  */
   7 package org.rocksdb.util;
   8
   9 import static java.nio.charset.StandardCharsets.UTF_8;
  10
  11 import java.nio.ByteBuffer;
  12 import java.util.ArrayList;
  13 import java.util.List;
  14
  15 public final class KVUtils {
  16
  17   /**
  18    * Get a byte array from a string.
  19    *
  20    * Assumes UTF-8 encoding
  21    *
  22    * @param string the string
  23    *
  24    * @return the bytes.
  25    */
  26   public static byte[] ba(final String string) {
  27     return string.getBytes(UTF_8);
  28   }
  29
  30   /**
  31    * Get a string from a byte array.
  32    *
  33    * Assumes UTF-8 encoding
  34    *
  35    * @param bytes the bytes
  36    *
  37    * @return the string.
  38    */
  39   public static String str(final byte[] bytes) {
  40     return new String(bytes, UTF_8);
  41   }
  42
  43   /**
  44    * Get a list of keys where the keys are named key1..key1+N
  45    * in the range of {@code from} to {@code to} i.e. keyFrom..keyTo.
  46    *
  47    * @param from the first key
  48    * @param to the last key
  49    *
  50    * @return the array of keys
  51    */
  52   public static List<byte[]> keys(final int from, final int to) {
  53     final List<byte[]> keys = new ArrayList<>(to - from);
  54     for (int i = from; i < to; i++) {
  55       keys.add(ba("key" + i));
  56     }
  57     return keys;
  58   }
  59
  60   public static List<ByteBuffer> keys(
  61       final List<ByteBuffer> keyBuffers, final int from, final int to) {
  62     final List<ByteBuffer> keys = new ArrayList<>(to - from);
  63     for (int i = from; i < to; i++) {
  64       final ByteBuffer key = keyBuffers.get(i);
  65       key.clear();
  66       key.put(ba("key" + i));
  67       key.flip();
  68       keys.add(key);
  69     }
  70     return keys;
  71   }
  72 }