title: Deserialize JSON into existing object (Java)
body: <p>I'd like to know how one might get the Jackson JSON library to deserialize JSON into an existing object? I've tried to find how to to this; but it seems to only be able to take a Class and instantiate it itself. </p>
  
  <p>Or if not possible, I'd like to know if any Java JSON deserialization libraries can do it. </p>
  
  <p>This seems to be a corresponding question for C#: <a href="https://stackoverflow.com/questions/5157079/overlay-data-from-json-string-to-existing-object-instance">Overlay data from JSON string to existing object instance</a>. It seems JSON.NET has a PopulateObject(string,object). </p>