@Override
  public PositionedByteRange setOffset(int offset) {
    this.position = 0;
    super.setOffset(offset);
    return this;
  }
Update the beginning of this range. {@code offset + length} may not be greater than
{@code bytes.length}. Resets {@code position} to 0. the new start of this range.
@return this.
hbase-common/src/main/java/org/apache/hadoop/hbase/util/AbstractPositionedByteRange.java