# Convert Java.Byte.Array to "normal" Arrays to send Binary Data via Cirrus Link MQTT

**URL:** <https://forum.inductiveautomation.com/t/convert-java-byte-array-to-normal-arrays-to-send-binary-data-via-cirrus-link-mqtt/56200>\
**Category:** Ignition\
**Created:** [February 16, 2022, 11:28am UTC](https://forum.inductiveautomation.com/t/convert-java-byte-array-to-normal-arrays-to-send-binary-data-via-cirrus-link-mqtt/56200 "2022-02-16T11:28:18Z")\
**Posts on this page:** 1\
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**Author:** ![justin.brzozoski](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/justin.brzozoski/32/13452_2.png) [@justin.brzozoski](https://forum.inductiveautomation.com/u/justin.brzozoski)\
**Post date:** [February 16, 2022, 5:51pm UTC](https://forum.inductiveautomation.com/t/convert-java-byte-array-to-normal-arrays-to-send-binary-data-via-cirrus-link-mqtt/56200/3 "2022-02-16T17:51:22Z")

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You may need a special hammer to fit an arbitrary Python byte string into a jarray that `writeFile` likes:

> [@\[IGN-4991, IGN-4996\]system.file.writeFile encoding](https://forum.inductiveautomation.com/t/ign-4991-ign-4996-system-file-writefile-encoding/19878/14):
>
> Once I decided the built in ways were broken, I just built a bigger hammer: def pythonByteString\_to\_jarray(pyString): return jarray.array(((x if x \< 128 else (x - 256)) for x in bytearray(pyString)),'b')

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