As Abhishek said, write the time and price in double quotation marks as "1449838598.0999202" and "52". Then you can save the string in Gson and then convert it to Json.
String str = "{"time": "1449838598.0999202", "Label": "Shirt", "Price": "52"}"; Gson gson = new Gson(); String json = gson.toJson(str);
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