I am trying to print a property from a JSON using SwiftyJSON on XCode (obviously with Swift language)

My first line prints well, but the second one prints nothing, I have checked the output of the first println() in an online parser and the striing is consistent:

```
var jdata = JSON(self.serverResponse)
println("jdata RAW: "+jdata.stringValue)
println("jdata.responseData: "+jdata["responseData"].stringValue)

```

This is the result of printing both things, as you can see the 2nd one is just blank:

```
jdata RAW: 
{
    "responseData": {
        "emotion":"",
        "lastinput":"What is your favourite color",
        "answer":"My favourite color is orange. What is yours?",
        "link": {
            "href":"",
            "target":""
        },
        "extraData": {
            "action":{"name":"displayClickableList","values":[{"label":"green","key":"1"},{"label":"yellow","key":"2"},{"label":"red","key":"3"}]},"type":"list"
        },
        "responseSession": {
            "id":"1ebfcd96c3c1f206dfb4087bc553",
            "transaction":"2"
        },
        "responseDetails": null,
        "responseStatus": 200,
        "applicationUrl": "http://moto-dev.cloud.com:88/moto-va-1/;jsessionid=1ebfc206dfb4087bc553"
    }
}

jdata.responseData: 

```

I am new to Swift, what is going wrong here?