JSON to JSON transformer

Try JOLT. It is a JSON to JSON transformation library written in Java. It was created on a project that was transforming lot of JSON from an ElasticSearch "backend" to a frontend api.

For the JSON transform you have listed in your problem, the Jolt "shift" spec would be :

// Jolt "shift" spec{    "OldObject": {        "Time": "NewObject.Time",           "Name": "NewObject.Title", // if the input has "OldObject.Name", copy it's value                                   // to "NewObject.Title        "quantity": "NewObject.quantity"    }}

You can do this transformation with JSON patch.

Example with jsonpatch-js:

var transformations = [  { move: '/OldObject', to: '/NewObject' },  { remove: '/NewObject/price' },  { move: '/NewObject/Name', to: '/NewObject/Title' }];var oldObject = { "OldObject": { "Time": 1351160457922, "Name": "OName", "quantity": 100, "price": 10 } };jsonpatch.apply(oldObject, transformations);

I did not test the provided, but should work like that.

There are Java implementations for JSON patch:

You can use ZORBA and JsonIQ http://www.jsoniq.org/However, it's a native library, it comes with a wrapper so you can use it in java.