Java – use gson to add an existing JSON string

I have a string object that contains some arbitrary JSON I want to wrap it in another JSON object, like this:

{
   version: 1,content: >>arbitrary_json_string_object<<
}

How can I reliably add my JSON string as an attribute without having to build it manually (that is, avoid cumbersome string concatenation)?

class Wrapper {
   int version = 1;
}

gson.toJson(new Wrapper())
// Then what?

Note that the added JSON should not be escaped, but as part of the wrapper of a valid JSON entity, such as:

{
   version: 1,content: ["the content",{name:"from the String"},"object"]
}

given

String arbitraryJson = "[\"the content\",{name:\"from the String\"},\"object\"]";

Solution

This is my solution:

Gson gson = new Gson();
  Object object = gson.fromJson(arbitraryJson,Object.class);

  Wrapper w = new Wrapper();
  w.content = object;

  System.out.println(gson.toJson(w));

There I changed your wrapper class:

// setter and getters omitted
public class Wrapper {
  public int version = 1;
  public Object content;
}

If you want to hide the details of deserialization / serialization, you can also write a custom serializer for wrapper