DecimalType: Parsing floats with a lowercase "e" separating mantissa and exponent fails

[abbe79]

Hi,
using stable 3.3 I get following entry in my log file when my PV inverter sends really small wattage values at night:

Incoming payload '5.605193857299268e-45' not supported by type 'NumberValue'

Seems like NumberValue/DecimalType/Number does not like the lowercase "e", separating mantissa and exponent.

Using an uppercase "E" (-> 5.605193857299268E-45) works.

While I could work around this using a transformation, I think others could fall in this trap too, because this is the notation that is used by C++ (and probably other languages too), see https://cplusplus.com/reference/ios/scientific/

Could this be changed to accept both notations? Thanks!

Expected Behavior

Float value 5.605193857299268e-45 should be parsed correctly to the "close to zero" value.
Using an uppercase E works as intended.

Current Behavior

Parsing fails and item is not updated. Log entry is:
2022-09-08 20:51:01.336 [WARN ] [ab.binding.mqtt.generic.ChannelState] - Incoming payload '5.605193857299268e-45' not supported by type 'NumberValue'

Possible Solution

Accept "e" and "E".

Steps to Reproduce (for Bugs)

In my case: Send 5.605193857299268e-45 to an mqtt number channel.

Your Environment

• Version used: openHAB 3.3

[abbe79]

Also reported here: openhab/openhab-addons#13371