I added as this but it throws the error saying, 'Failed to convert value of type 'java.lang.String' to required type 'java.util.ArrayList'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [java.lang.String] to required type [java.util.ArrayList]: no matching editors or conversion strategy found'. 

I have tried this early too when you said me to do so, but it didn't work as expected all those times. That is why i am still keeping this logic.