Alexa conversational skill Error - amazon-web-services

Question

I'm creating a skill in Alexa that does the following.
User : Hi
Alexa, hello please give me your name
User : John
Alexa : Hi John, good to meet you. How old are you
User : 25
Below are my intents
{
"intents": [
{
"intent": "StartTheFlow",
"slots": [
{
"name": "custName",
"type": "list_of_userNames"
},
{
"name": "age",
"type": "AMAZON.NUMBER"
}
]
},
{
"intent": "AMAZON.HelpIntent"
},{
"intent": "Welcome"
},
{
"intent": "AMAZON.StopIntent"
},
{
"intent": "AMAZON.CancelIntent"
}
]
}
And below are my utterances
StartTheFlow Hi
StartTheFlow {custName}
StartTheFlow {age}
Below is my onIntent()
#Override
public SpeechletResponse onIntent(final IntentRequest request, final Session session) throws SpeechletException {
log.info("onIntent requestId={}, sessionId={}", request.getRequestId(), session.getSessionId());
Intent intent = request.getIntent();
String intentName = (intent != null) ? intent.getName() : null;
if ("StartTheFlow".equals(intentName)) {
return getTheFlow(intent, session);
} else if ("AMAZON.HelpIntent".equals(intentName)) {
return getHelpResponse();
} else if ("WelcomeChubb".equals(intentName)) {
return getWelcomeResponse();
} else {
throw new SpeechletException("Invalid Intent");
}
}
And I'm trying to handle this as below
private SpeechletResponse getTheFlow(Intent intent, Session session) {
boolean isAskResponse = true;
String responseText = "";
String nameFromSession = (String) session.getAttribute("name");
if (StringUtils.isNullOrEmpty(nameFromSession)) {
responseText = "please give me your name";
getTheNameText(intent, session);
} else {
System.out.println(session.getAttribute("nameFromSession"));
responseText = "please give me your date of birth";
}
return getSpeechletResponse(responseText, "", isAskResponse);
}
private String getTheNameText(Intent intent, Session session) {
String userNameFrmIntent = getNameFromSlot(intent).toString();
session.setAttribute("nameFromSession", userNameFrmIntent);
return getNameFromSlot(intent).toString();
}
private String getNameFromSlot(Intent intent) {
Slot userName = intent.getSlot(Slot_Name);
return userName.getValue();
}
Also, I've defined a slot in the top as below.
private static final String Slot_Name = "custName";
But here when I type Hi, Instead of asking me my name, it is giving me an error in logs it shows Java NullPointer Exception. the response that I get when I type Hi is as below.
{
"session": {
"sessionId": "SessionId.a2740ca4-73ff-4a15-856d-6461b3c7b2e1",
"application": {
"applicationId": "amzn1.ask.skill.e3dfb30e-0089-423c-a325-30ad28dd2e2b"
},
"attributes": {},
"user": {
"userId": "amzn1.ask.account.AEQYTT5HFHEGGDSUCT3NW45HKR7O3FBL5YCBSZIS7P5LNP5BXFEMUR7AUYOZVKC2FT5V6RKJC7RNA5VMZVREBAXAQP3NFNTQSFSSKSEXIYT4FQYMS5JCI2CCAOPUF4FN4C6DHEU6ONNY3D6GN5AWK75KOQNJH2IWROIIXTPNXSNI6FLQYRBBMP7TRSOWVNCY73WJUT2VLHDACWA"
},
"new": true
},
"request": {
"type": "IntentRequest",
"requestId": "EdwRequestId.cf686fc0-cbfd-4496-bb09-c41714563507",
"locale": "en-US",
"timestamp": "2017-02-15T20:12:44Z",
"intent": {
"name": "StartTheFlow",
"slots": {
"custName": {
"name": "custName",
"value": "hi"
}
}
}
},
"version": "1.0"
}
Can someone please let me know where am I going wrong and how can I fix this, I've quite a number of questions to be linked, like 25, can Someone please let me know if there is a better way to do this in java.
Thanks

Answer 1

I would recommend creating a separate intent for each thing that the user says. So for example, HelloIntent, NameIntent, and AgeIntent.
Then be sure to pass those bits of information forward to all following intents in the session. So each intent could use a common function at the beginning to read each string from the session (if exists), add the new slot data to it, and then write all the strings back to the response session before finishing.
Since you'll then have separate intents, and the user could conceivably say them out of order, you may want to check that all the needed strings have been entered, or else prompt the user for any missing strings.
The problem with saving data in the session is that the data will be gone the next time the user starts the skill. To resolve this, you could use a database to hold the users data, saving it keyed to the userId. There are lots of examples on how to do that. Be careful that some databases are essentially free, but others will charge you depending on how many times it is used each month.