bufDataOffset = totalParameterCount; // data comes right after data

            int available = maxBufferSize - parameterOffset;
            parameterCount = Math.min( totalParameterCount, available );
            available -= parameterCount;

            dataOffset = parameterOffset + parameterCount;
            pad1 = dataOffset % PADDING_SIZE;

            end = Math.max(end, this.headerStart + this.parameterOffset + this.parameterCount + this.pad2);
        }

        if ( this.dataCount > 0 ) {
            System.arraycopy(this.txn_buf, this.bufDataOffset, dst, this.headerStart + this.dataOffset, this.dataCount);
            this.bufDataOffset += this.dataCount;
            end = Math.max(end, this.headerStart + this.dataOffset + this.dataCount);