title: Adding an existing json string with Gson
body: <p>I have a String object containing some arbitrary json. I want to wrap it inside another json object, like this:</p>
  
  <pre><code>{
     version: 1,
     content: &gt;&gt;arbitrary_json_string_object&lt;&lt;
  }
  </code></pre>
  
  <p>How can I reliably add my json string as an attribute to it without having to build it manually (ie avoiding tedious string concatenation)?</p>
  
  <pre><code>class Wrapper {
     int version = 1;
  }
  
  gson.toJson(new Wrapper())
  // Then what?
  </code></pre>
  
  <p>Note that the added json should <em>not</em> be escaped, but a be part of the wrapper as a valid json entity, like this:</p>
  
  <pre><code>{
     version: 1,
     content: ["the content", {name:"from the String"}, "object"]
  }
  </code></pre>
  
  <p>given</p>
  
  <pre><code>String arbitraryJson = "[\"the content\", {name:\"from the String\"}, \"object\"]";
  </code></pre>