@Override
  public long skip(long n) {
    long k = Math.min(n, available());
    if (k <= 0) {
      return 0;
    }
    this.buf.skip((int) k);
    return k;
  }
Skips <code>n</code> bytes of input from this input stream. Fewer bytes might be skipped if the
end of the input stream is reached. The actual number <code>k</code> of bytes to be skipped is
equal to the smaller of <code>n</code> and remaining bytes in the stream.
@param n the number of bytes to be skipped.
@return the actual number of bytes skipped.
hbase-common/src/main/java/org/apache/hadoop/hbase/io/ByteBuffInputStream.java