[Moo] JSON encoding Class instances

[Blackbird]

Hi,


I'm using Mootools classes extensively in my business logic. I would
like to encode only the "options" of corresponding instances in JSON.
Automatically.


Let me take an example. Encoding an instance of the following class:

########
var Activity = new Class({
    Implements: [Options],

        initialize: function(options) {
                this.options = options;
        },

        options: {  // Defaults
                "vehicles": []
        },

        getId: function() {
                return this.options.id;
        },

        getStartDateTime: function() {
                return this.options.startDateTime;
        },

        getEndDateTime: function() {
                return this.options.endDateTime;
        },

        getOriginStation: function() {
                return this.options.originStation;
        },

        getDestinationStation: function() {
                return this.options.destinationStation;
        },

        getComment: function() {
                return this.options.comment;
        },

        getVehicles: function() {
                return this.options.vehicles;
        }
});
########


Now, calling "JSON.encode(myActivity)" will result in the following
JSON:

########
{
    "options":{
        "startDateTime":"2011-11-11T05:12:22.850Z",
        "endDateTime":"2011-11-11T05:27:22.850Z",
        "originStation":{
            "$caller":null,
            "caller":null,
            "options":{
                "code":"CST",
                "name":"Stockholm C"
            }
        },
        "destinationStation":{
            "$caller":null,
            "caller":null,
            "options":{
                "code":"CST",
                "name":"Stockholm C"
            }
        },
        "vehicles":[
            {
                "$caller":null,
                "caller":null,
                "options":{
                    "id":"2110",
                    "type":"RABe525"
                }
            }
        ],
        "trainNumber":"8424",
        "tractionType":"M1"
    },
    "$caller":null,
    "caller":null
}
########


But I would like only the "options" to be encoded, which would result
in the following JSON:

########
{
    "startDateTime":"2011-11-11T05:12:22.850Z",
    "endDateTime":"2011-11-11T05:27:22.850Z",
    "originStation":{
        "code":"CST",
        "name":"Stockholm C"
    },
    "destinationStation":{
        "code":"CST",
        "name":"Stockholm C"
    },
    "vehicles":[
        {
            "id":"2110",
            "type":"RABe525"
        }
    ],
    "trainNumber":"8424",
    "tractionType":"M1"
}
########


Is there a way to do this automatically?