Question

I am just getting started with some Jackson JSON data here. This section is giving me trouble.

"pointData":{
    "1":"32.1093904, 66.7065216", 
    "2":"33.1236854, 67.8128443", 
    "3":"32.9524550, 67.0013501"
}

It seems to me that having integers as the attribute name is illegal. Is this correct?

Answer 1

You’re correct that JSON cannot have integer attribute names, because all JSON attribute names must be quoted as yours are above, making them strings. See the flow here: http://json.org/

Also, your JSON structure above is invalid because it begins with an attribute name, but no object that the attribute is a part of. If you’re getting errors, this is why. A legal structure would be:

{"pointData":{
    "1":"32.1093904, 66.7065216", 
    "2":"33.1236854, 67.8128443", 
    "3":"32.9524550, 67.0013501"
    }
}

FYI, if you’re storing point data, a perhaps better structure would be:

{"pointData":{
    "1": {"x": 32.1093904, "y": 66.7065216}, 
    "2": {"x": 33.1236854, "y": 67.8128443}, 
    "3": {"x": 32.9524550, "y": 67.0013501}
    }
}

Notice two things about this structure:

1. Each point has an x and y property that are independently accessible.
2. The values of the x and y properties are numeric, not strings.