this.pad = this.pad1 = 0;
        if (this.parameterCount > 0) {
            bufferIndex += this.pad = this.parameterOffset - (bufferIndex - this.headerStart);
            System.arraycopy(buffer, bufferIndex, this.txn_buf, this.bufParameterStart + this.parameterDisplacement, this.parameterCount);
            bufferIndex += this.parameterCount;
        }
        if (this.dataCount > 0) {

        assertEquals(smbComNtTransaction.maxDataCount, SmbComTransaction.readInt4(dst, 15), "maxDataCount should be written correctly");
        assertEquals(smbComNtTransaction.parameterCount, SmbComTransaction.readInt4(dst, 19), "parameterCount should be written correctly");
        assertEquals(smbComNtTransaction.parameterOffset, SmbComTransaction.readInt4(dst, 23),
                "parameterOffset should be written correctly");

            return totalParameterCount;
        }

        int getTotalDataCount() {
            return totalDataCount;
        }

        int getParameterCount() {
            return parameterCount;
        }

        int getDataCount() {
            return dataCount;
        }

        int getSetupCount() {
            return setupCount;
        }

            // caclulate parameterDisplacement before calculating new parameterCount
            this.parameterDisplacement += this.parameterCount;

            int available = this.maxBufferSize - this.parameterOffset - this.pad1;
            this.parameterCount = Math.min(this.totalParameterCount - this.parameterDisplacement, available);
            available -= this.parameterCount;

            parameterDisplacement += parameterCount;

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

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

        pad = pad1 = 0;
        final int n;

        if (parameterCount > 0) {
            bufferIndex += pad = parameterOffset - (bufferIndex - headerStart);
            System.arraycopy(buffer, bufferIndex, txn_buf, bufParameterStart + parameterDisplacement, parameterCount);
            bufferIndex += parameterCount;
        }
        if (dataCount > 0) {

        // totalParameterCount = 10
        writeInt4(10, buffer, bufferIndex);
        bufferIndex += 4;
        // totalDataCount = 20
        writeInt4(20, buffer, bufferIndex);
        bufferIndex += 4;
        // parameterCount = 5
        writeInt4(5, buffer, bufferIndex);
        bufferIndex += 4;
        // parameterOffset = 30
        writeInt4(30, buffer, bufferIndex);
        bufferIndex += 4;
        // parameterDisplacement = 0

            dstIndex += 4;
            writeInt4(maxDataCount, dst, dstIndex);
            dstIndex += 4;
        }
        writeInt4(parameterCount, dst, dstIndex);
        dstIndex += 4;
        writeInt4(parameterCount == 0 ? 0 : parameterOffset, dst, dstIndex);
        dstIndex += 4;
        if (command == SMB_COM_NT_TRANSACT_SECONDARY) {
            writeInt4(parameterDisplacement, dst, dstIndex);

            this.bufDataStart = this.totalParameterCount;
        }
        bufferIndex += 4;
        this.totalDataCount = SMBUtil.readInt4(buffer, bufferIndex);
        bufferIndex += 4;
        this.parameterCount = SMBUtil.readInt4(buffer, bufferIndex);
        bufferIndex += 4;
        this.parameterOffset = SMBUtil.readInt4(buffer, bufferIndex);
        bufferIndex += 4;

        if (bufDataStart == 0) {
            bufDataStart = totalParameterCount;
        }
        bufferIndex += 4;
        totalDataCount = readInt4(buffer, bufferIndex);
        bufferIndex += 4;
        parameterCount = readInt4(buffer, bufferIndex);
        bufferIndex += 4;
        parameterOffset = readInt4(buffer, bufferIndex);
        bufferIndex += 4;
        parameterDisplacement = readInt4(buffer, bufferIndex);