Convert Hex String to Dec to Float

Setup, Configuration and Use Beginners
1

Via the serial inteface I get a string with hexadecimal values of a sensor.
Now I’m having trouble converting the String to a float which shall be used for further calculations.
For testing purposes this calculation is a division by 100 which should result in an integer with some decimals.

target item:

Number nSensorVal          "val= [%.2f]"

rule:

var Number nIntVal
var Number nFloatVal
nIntVal = Integer::parseInt(sHexString, 16)      // this works!
nFloatVal = ???  / 100                           // no idea what to put here
nSensorVal.postUpdate(nFloatVal)

In place of ??? I’ve unsucessfully tried using things like
nFloatVal = Float::parseFloat(nIntVal.state)
or
nFloatVal = (nIntVal.state as DecimalType) / 100

I get a lot of errors like
The name ‘XFeatureCallImplCustom.state’ cannot be resolved to an item or type.
which to my knowledge indicates a type mismatch.

So how is an integer value converted to float to preserve decimal places when doing calculations?
Maybe that’s even possible in a single step?

2

nIntVal is just a variable, it is not an Item as you would define in an .items file. So it doesn’t have a .state, that’s for Items.
nIntVal is already already a number, you defined it that way.
Have you tried simply
nFloatVal = nIntVal / 100
?

3

After a lot of testing I’ve found the following solution:

import java.lang.*
var int nIntVal
var Number nFloatVal
nIntVal = Integer::parseInt(sHexString, 16)
nFloatVal = nIntVal.floatValue()  / 100

I’m not sure if there’s a better way to this.
But one thing I’d like to improve is the import. As you can see pretty much everything is imported at the moment. I’d rather import the necessary libs only.
So for the example above, what are the required imports?