long ioff = 0;
                        for ( int i = 0; i < chunks; i++ ) {
                            long absoff = ooff + ioff;
                            int csize = i == chunks - 1 ? lastChunkSize : maxChunkSize;
                            chunkInfo[ i ] = new SrvCopychunk(absoff, absoff, csize);
                            ioff += maxChunkSize;
                        }

        i = j = 0;
    }
    public void update(byte[] src, int soff, int slen, byte[] dst, int doff)
    {
        int slim;

        slim = soff + slen;
        while (soff < slim) {
            i = (i + 1) & 0xff;
            j = (j + s[i]) & 0xff;
            byte t = s[i];
            s[i] = s[j];
            s[j] = t;
            dst[doff++] = (byte)(src[soff++] ^ s[(s[i] + s[j]) & 0xff]);
        }
    }

    private long sourceOffset;
    private long targetOffset;
    private int length;


    /**
     * @param soff
     * @param toff
     * @param len
     */
    public SrvCopychunk ( long soff, long toff, int len ) {
        this.sourceOffset = soff;
        this.targetOffset = toff;
        this.length = len;
    }


    /**
     * {@inheritDoc}
     *

John Howard <******@****.***> 1578852924 -0800

Shinsuke Sugaya <******@****.***> 1576358545 +0900

Shinsuke Sugaya <******@****.***> 1576358545 +0900

   * single "stop" control is required to interrupt or turn off ancillary devices, DC4 is the
   * preferred assignment.)
   *
   * @since 8.0
   */
  public static final byte DC3 = 19; // aka XOFF

  /**
   * Transmission off. See {@link #XON} for explanation.
   *
   * @since 8.0
   */
  public static final byte XOFF = 19; // aka DC3

  /**

Shinsuke Sugaya <******@****.***> 1576358545 +0900

Shinsuke Sugaya <******@****.***> 1576358545 +0900

   * single "stop" control is required to interrupt or turn off ancillary devices, DC4 is the
   * preferred assignment.)
   *
   * @since 8.0
   */
  public static final byte DC3 = 19; // aka XOFF

  /**
   * Transmission off. See {@link #XON} for explanation.
   *
   * @since 8.0
   */
  public static final byte XOFF = 19; // aka DC3

  /**