client data integration

[sipungora]

Hi,

I have two data sets
profile.data.xml

<profiles>
  <profile>
    <nickname>u1</nickname>
    <rating>4</rating>
  </profile>
  <profile>
    <nickname>u2</nickname>
    <rating>5</rating>
  </profile>
  <profile>
    <nickname>u3</nickname>
    <rating>3</rating>
  </profile>
  <profile>
    <nickname>u4</nickname>
    <rating>4</rating>
  </profile>
</profiles>

and state.data.xml

<states>
  <state>
    <online>true</online>
    <nickname>u1</nickname>
  </state>
  <state>
    <online>true</online>
    <nickname>u2</nickname>
  </state>
  <state>
    <online>false</online>
    <nickname>u3</nickname>
  </state>
  <state>
    <online>false</online>
    <nickname>u4</nickname>
  </state>
</states>

I want a grid with fields: nickname, state, rating. Is it possible to join both data sources?
This is my java code:

    public static ProfileXmlDS getInstance() {
        if (instance == null) {
            instance = new ProfileXmlDS("profileDS");
        }
        return instance;
    }

    public ProfileXmlDS(String id) {
        setID(id);
        setRecordXPath("/profiles/profile");
  
        DataSourceTextField nameField = new DataSourceTextField("nickname");
        nameField.setPrimaryKey(true);

        DataSourceIntegerField ratingField = new DataSourceIntegerField("rating");

        setFields(nameField, ratingField);

        setDataURL("data/profile.data.xml");
        setClientOnly(true);
    }

    public StateXmlDS(String id) {
    	ClientModel clientModel = ClientController.getInstance().getModel();
    	Model model = clientModel.getModel();
        setID(id);
        setRecordXPath("/states/state");

        DataSourceTextField nameField = new DataSourceTextField("nickname", "Expert");
        nameField.setPrimaryKey(true);
        nameField.setForeignKey("profileDS.nickname");

        DataSourceBooleanField statusField = new DataSourceBooleanField("online", "Online");

        setFields(nameField, statusField);

	setDataURL("data/state.data.xml");
        setClientOnly(true);
    }

        ListGrid gr = new ListGrid();
        gr.setDataSource(StateXmlDS.getInstance());
        gr.setShowAllRecords(true);
	gr.setAutoFetchData(true);
		
	ListGridField f1 = new ListGridField("nickname");
	ListGridField f2 = new ListGridField("online");
	ListGridField f3 = new ListGridField("rating");
		
	gr.setFields(f1, f2, f3);

What should I change in order it works?

Thanks in advance.