Struts2 Convert json array to java object array - not LinkedHashmap

First off my question is very similar to below however I'm not sure if the answers are applicable to my specific problem or whether I just need clarification about how to approach it: Convert LinkedHashMap<String,String> to an object in Java

I am using struts2 json rest plugin to convert a json array into a java array. The array is sent through an ajax post request and the java receives this data. However instead of being the object type I expect it is received as a LinkedHashmap. Which is identical to the json request in structure.

[
    {advance_Or_Premium=10000, available=true},
    {advance_Or_Premium=10000, available=true},
    {advance_Or_Premium=10000, available=true}
]

The data is all present and correct but just in the wrong type. Ideally I want to send the data in my object type or if this is not possible convert the LinkedHashMap from a list of keys and values into the object array. Here is the class I am using, incoming data is received in the create() method:

@Namespace(value = "/rest")
public class OptionRequestAction extends MadeAbstractAction implements ModelDriven<ArrayList<OptionRequestRest>>
{
  private String id;

  ArrayList<OptionRequestRest> model = new ArrayList<OptionRequestRest>();

  public HttpHeaders create()
  {
    // TODO - need to use model here but it's a LinkedHashmap
    return new DefaultHttpHeaders("create");
  }

  public String getId()
  {
    return this.id;
  }

  public ArrayList<OptionRequestRest> getModel()
  {
    return this.model;
  }

  public ArrayList<OptionRequestRest> getOptionRequests()
  {
    @SuppressWarnings("unchecked")
    ArrayList<OptionRequestRest> lReturn = (ArrayList<OptionRequestRest>) this.getSession().get("optionRequest");

    return lReturn;
  }

  // Handles /option-request GET requests
  public HttpHeaders index()
  {
    this.model = this.getOptionRequests();
    return new DefaultHttpHeaders("index").lastModified(new Date());

  }

  public void setId(String pId)
  {
    this.id = pId;
  }

  public void setModel(ArrayList<OptionRequestRest> pModel)
  {
    this.model = pModel;
  }

  // Handles /option-request/{id} GET requests
  public HttpHeaders show()
  {
    this.model = this.getOptionRequests();
    return new DefaultHttpHeaders("show").lastModified(new Date());
  }
}

One of the things which is confusing me is that this code works fine and returns the correct object type if the model is not an array. Please let me know if my question is not clear enough and needs additional information. Thanks.