hbase-common/src/main/java/org/apache/hadoop/hbase/util/PositionedByteRange.java

   1 /*
   2  * Licensed to the Apache Software Foundation (ASF) under one
   3  * or more contributor license agreements.  See the NOTICE file
   4  * distributed with this work for additional information
   5  * regarding copyright ownership.  The ASF licenses this file
   6  * to you under the Apache License, Version 2.0 (the
   7  * "License"); you may not use this file except in compliance
   8  * with the License.  You may obtain a copy of the License at
   9  *
  10  *     http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  * Unless required by applicable law or agreed to in writing, software
  13  * distributed under the License is distributed on an "AS IS" BASIS,
  14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  * See the License for the specific language governing permissions and
  16  * limitations under the License.
  17  */
  18
  19 package org.apache.hadoop.hbase.util;
  20
  21
  22 import org.apache.yetus.audience.InterfaceAudience;
  23
  24 /**
  25  * <p>
  26  * Extends {@link ByteRange} with additional methods to support tracking a
  27  * consumers position within the viewport. The API is extended with methods
  28  * {@link #get()} and {@link #put(byte)} for interacting with the backing
  29  * array from the current position forward. This frees the caller from managing
  30  * their own index into the array.
  31  * </p>
  32  * <p>
  33  * Designed to be a slimmed-down, mutable alternative to {@link java.nio.ByteBuffer}.
  34  * </p>
  35  */
  36 @InterfaceAudience.Public
  37 public interface PositionedByteRange extends ByteRange {
  38
  39   // net new API is here.
  40
  41   /**
  42    * The current {@code position} marker. This valuae is 0-indexed, relative to
  43    * the beginning of the range.
  44    */
  45   public int getPosition();
  46
  47   /**
  48    * Update the {@code position} index. May not be greater than {@code length}.
  49    * @param position the new position in this range.
  50    * @return this.
  51    */
  52   public PositionedByteRange setPosition(int position);
  53
  54   /**
  55    * The number of bytes remaining between position and the end of the range.
  56    */
  57   public int getRemaining();
  58
  59   /**
  60    * Retrieve the next byte from this range without incrementing position.
  61    */
  62   public byte peek();
  63
  64   /**
  65    * Retrieve the next byte from this range.
  66    */
  67   public byte get();
  68
  69   /**
  70    * Retrieve the next short value from this range.
  71    */
  72   public short getShort();
  73
  74   /**
  75    * Retrieve the next int value from this range.
  76    */
  77   public int getInt();
  78
  79   /**
  80    * Retrieve the next long value from this range.
  81    */
  82   public long getLong();
  83
  84   /**
  85    * Retrieve the next long value, which is stored as VLong, from this range
  86    * @return the long value which is stored as VLong
  87    */
  88   public long getVLong();
  89
  90   /**
  91    * Fill {@code dst} with bytes from the range, starting from {@code position}.
  92    * This range's {@code position} is incremented by the length of {@code dst},
  93    * the number of bytes copied.
  94    * @param dst the destination of the copy.
  95    * @return this.
  96    */
  97   public PositionedByteRange get(byte[] dst);
  98
  99   /**
 100    * Fill {@code dst} with bytes from the range, starting from the current
 101    * {@code position}. {@code length} bytes are copied into {@code dst},
 102    * starting at {@code offset}. This range's {@code position} is incremented
 103    * by the number of bytes copied.
 104    * @param dst the destination of the copy.
 105    * @param offset the offset into {@code dst} to start the copy.
 106    * @param length the number of bytes to copy into {@code dst}.
 107    * @return this.
 108    */
 109   public PositionedByteRange get(byte[] dst, int offset, int length);
 110
 111   /**
 112    * Store {@code val} at the next position in this range.
 113    * @param val the new value.
 114    * @return this.
 115    */
 116   public PositionedByteRange put(byte val);
 117
 118   /**
 119    * Store short {@code val} at the next position in this range.
 120    * @param val the new value.
 121    * @return this.
 122    */
 123   public PositionedByteRange putShort(short val);
 124
 125   /**
 126    * Store int {@code val} at the next position in this range.
 127    * @param val the new value.
 128    * @return this.
 129    */
 130   public PositionedByteRange putInt(int val);
 131
 132   /**
 133    * Store long {@code val} at the next position in this range.
 134    * @param val the new value.
 135    * @return this.
 136    */
 137   public PositionedByteRange putLong(long val);
 138
 139   /**
 140    * Store the long {@code val} at the next position as a VLong
 141    * @param val the value to store
 142    * @return number of bytes written
 143    */
 144   public int putVLong(long val);
 145
 146   /**
 147    * Store the content of {@code val} in this range, starting at the next position.
 148    * @param val the new value.
 149    * @return this.
 150    */
 151   public PositionedByteRange put(byte[] val);
 152
 153   /**
 154    * Store {@code length} bytes from {@code val} into this range. Bytes from
 155    * {@code val} are copied starting at {@code offset} into the range, starting at
 156    * the current position.
 157    * @param val the new value.
 158    * @param offset the offset in {@code val} from which to start copying.
 159    * @param length the number of bytes to copy from {@code val}.
 160    * @return this.
 161    */
 162   public PositionedByteRange put(byte[] val, int offset, int length);
 163
 164   /**
 165    * Limits the byte range upto a specified value. Limit cannot be greater than
 166    * capacity
 167    *
 168    * @param limit
 169    * @return PositionedByteRange
 170    */
 171   public PositionedByteRange setLimit(int limit);
 172
 173   /**
 174    * Return the current limit
 175    *
 176    * @return limit
 177    */
 178   public int getLimit();
 179
 180   // override parent interface declarations to return this interface.
 181
 182   @Override
 183   public PositionedByteRange unset();
 184
 185   @Override
 186   public PositionedByteRange set(int capacity);
 187
 188   @Override
 189   public PositionedByteRange set(byte[] bytes);
 190
 191   @Override
 192   public PositionedByteRange set(byte[] bytes, int offset, int length);
 193
 194   @Override
 195   public PositionedByteRange setOffset(int offset);
 196
 197   @Override
 198   public PositionedByteRange setLength(int length);
 199
 200   @Override
 201   public PositionedByteRange get(int index, byte[] dst);
 202
 203   @Override
 204   public PositionedByteRange get(int index, byte[] dst, int offset, int length);
 205
 206   @Override
 207   public PositionedByteRange put(int index, byte val);
 208
 209   @Override
 210   public PositionedByteRange putShort(int index, short val);
 211
 212   @Override
 213   public PositionedByteRange putInt(int index, int val);
 214
 215   @Override
 216   public PositionedByteRange putLong(int index, long val);
 217
 218   @Override
 219   public PositionedByteRange put(int index, byte[] val);
 220
 221   @Override
 222   public PositionedByteRange put(int index, byte[] val, int offset, int length);
 223
 224   @Override
 225   public PositionedByteRange deepCopy();
 226
 227   @Override
 228   public PositionedByteRange shallowCopy();
 229
 230   @Override
 231   public PositionedByteRange shallowCopySubRange(int innerOffset, int copyLength);
 232 }