hallo Michael
I'm sorry that it is so incomprehensible.

I will be as a kind of built like a simple editor,
evaluate the text files and reads with them interactively with the help of GeoTools

Therefore I need the one with shapfile geometries and the other a sld-file with styles.
sld-file for simplicity in this example is applied statically.
I want to create styles for later programmatically.

now... what do i
have to do if i want to change a value of a layer in memory? what i'm trying to do is,
write a new value in the store. i tried using store.modifyFeatures() and a transaction....

it seems like layer is not going to be changed? or maybe im totaly on the wrong way in how to change the data? i would really appreciate your help guys.