From the javadoc: Utility method to take a string and convert it to normal Java variable name capitalization.
In your case you apply this function to the getter function, which is already modified(first letter of the property is capitalized). So it is improper use of decapitalize function.
Using it in hibernate leads to the problem, that using Field access aB property and AB property are different, but for property access aB and AB are the same and only AB will be used. So I cannot use f.e. as in my case hClassCode property, I should use HClassCode which is bad practice for naming properties or hclassCode which is bad too for me.

It would be kind of you to re-open this issue.