public void updateEvent(String key, String value) {
        updateEvent(key, value, true, true);
    }
public void updateEvent ( String key , String value ) { updateEvent ( key , value , true , true ) ; }
Update the current event with given key and value, if current event not
available, add a new one into array

@param key The variable's key for a event
@param value The input value for the key