SyntaxError: JSON.parse: expected property name or '}'
<p>I'm using the following code, trying to send the JSON line to the client, for testing purposes:</p>

<pre><code>String json = "{'nombre':'Donell', 'dni':'351351P'}";
            response.setContentType("application/json");
            PrintWriter out = response.getWriter();
            JSONObject jsonObj = (JSONObject) JSONValue.parse(json);
            out.print(jsonObj);
</code></pre>

<p>I'm using the library json-simple, but this isn't working. When I access to "/Prueba", which is my test servlet, I receive a package with 200 code type "json", but without data:</p>

<p><a href="https://i.stack.imgur.com/Bk20m.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Bk20m.png" alt="enter image description here"></a></p>

<p>What's wrong here? Thank you!</p>

<p>edit: When trying to just write the json, I see it, but with an error:</p>

<p><a href="https://i.stack.imgur.com/cMjVi.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/cMjVi.png" alt="enter image description here"></a></p>