Question

I have a tree, to be displayed on the screen, which is basically a JSON object. I want to send this JSON object to the Java class as a request parameter.

Following is a sample of the JSON object:

// Root node
var rootNode = { Content: "Root", Nodes:[] };
// First Level
rootNode.Nodes[0] = { Content: "Employee Code", navigationType: "0"};
rootNode.Nodes[1] = { Content: "Problem Area", navigationType: "1" };
// Second Level
rootNode.Nodes[1].Nodes = [{ Content : "ACC-HO", Collapsed: true},
                           { Content : "ACC-SALES" },
                           { Content : "BUSI. HEAD", ToolTip: "Click ME!" },
                           { Content : "CEO"}
                          ];

Now the plugin, which creates this tree out of the JSON object, stores the reference of the Parent Node in each of the nodes. Hence this results in a circular reference where a node stores reference of its children and each child node stores the reference of its Parent

Due to this I am unable to use JSON.stringify(rootNode)

I want to send the rootNode object as a request parameter using Ajax. I have done the following:

$.ajax({
    type : "POST",
    url : "treeDemo_!saveTree",
            data: {treeObject: JSON.stringify(rootNode) },
            success : function(resp) {      
        alert('success');
    }
});

But as I mentioned, JSON.stringify doesnt work in my case. So can anyone suggest an alternative way to send the JSON object as a request parameter which I can receive in the Java code and process further?

Answer 1

A solution, if you can’t clean the plugin, is to clone the rootNode object and in the process don’t copy the ‘Parent’ property :

function goclone(source) {
    if (Object.prototype.toString.call(source) === '[object Array]') {
        var clone = [];
        for (var i=0; i<source.length; i++) {
            clone[i] = goclone(source[i]);
        }
        return clone;
    } else if (typeof(source)=="object") {
        var clone = {};
        for (var prop in source) {
            if (source.hasOwnProperty(prop) && prop!='Parent') {
                clone[prop] = goclone(source[prop]);
            }
        }
        return clone;
    } else {
        return source;
    }
}

var serializableRootNode = goclone(rootNode);

The serializableRootNode doesn’t contain the ‘Parent’ properties.

Adapt the code if the parent reference isn’t called exactly ‘Parent’.