Transform String for single value

I recently updated my Z-Wave binding and devices. I have a BE469 Schlage Deadbolt and in my rules I used to get the Alarm value to tell if the lock was locked or unlocked. Now that the device was updated I use the Alarm RAW value and it returns a string. I’m trying to get the event number from the string and set it to a var so I can update my lock status.
Here is the string in the event log:
{“notification”:“ACCESS_CONTROL__MANUAL_UNLOCK”,“type”:“ACCESS_CONTROL”,“event”:“2”,“status”:“255”}
Here is how I’m trying to get the event numberin my rule:
var Number lockevent = new Integer(transform(“JSONPATH”, “$.event”, “zwave:device:8fe51373:node41:alarm_raw”))
And here is the error I’m getting in the openhab log:
Error executing the transformation ‘JSONPATH’: Invalid path ‘$.event’ in ‘zwave:device:8fe51373:node41:alarm_raw’

How do I get the event number so I can change the lock status?

I found my answer:
var Number lockevent = Integer::parseInt(transform(“JSONPATH”, “$.event”, “Lock_MF_Dining_Alarm.state.toString”))