Code shown below works well when JSON object contains jsonKey as it was passed to the method. I wonder ... if there is a way to get a value assigne
Unfortunately there doesn't seem to be a way in the current implementation to do this. If you look at the Gson source and more specifically at the JsonObject implementation you will see that the underlying data structure is a linked hash map. The get call simply invokes the get on the map, which in turn uses the hash code and equals method of your key to find the object you are looking for.
The only way around is to enforce some naming conventions for you keys. The easiest way would be to force all the keys to lowercase. If you need mixed case keys then you will have more difficulty and will need to write a more sophisticated algorithm for transforming the keys instead of simply calling jsonKey.toLowerCase().