GWT JSNI: pass js element to gwt Element will lose all children - gwt

Question

I was trying to wrap some jquery function to GWT, run below js code, the size is 2.
var html="<div><p>paragraph</p><div>second</div></div>";
var size=$(html).get(0).children.length;
alert(size);
but run below GWT code
select(html).get(0).getChildCount();
just return 0, the select function is like below:
public class JQuery extends JavaScriptObject {
protected JQuery() {
}
public static final native JQuery select(String selector) /*-{
return $wnd.jQuery(selector);
}-*/;
public final native Element get(int index) /*-{
return this.get(index) || null;
}-*/;
}
I'd like to know why it just loses the children elements from JSNI method, and what's the right way to this wrapping to let it behave exactly same to native jquery?
Thanks.
-------------EDIT------------------------------------------------------------
I test above JSNI code in a real gwt project and it works fine, the children elements are returned from js to java. But in GwtTestCase problem exists.
public class JQueryTest extends GWTTestCase {
#Override
public String getModuleName() {
return "com.jsnitest.JsniTest";
}
public void testSelectHtml() {
ScriptInjector.fromUrl("http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js").setWindow(
ScriptInjector.TOP_WINDOW).setCallback(new Callback<Void, Exception>() {
#Override
public void onFailure(Exception reason) {
}
#Override
public void onSuccess(Void result) {
int childCount = select("<div><p>paragraph</p><div>second</div><ul></ul></div>").get(0).getChildCount();
//Fail! childCount=0
assertEquals(3, childCount);
}
}).inject();
}
}

Answer 1

gwtquery a.k.a. gQuery is a jQuery-like API written in GWT.
Following the principle of DRY, I would use this library instead of wrapping jQuery.
The only reason I see to wrap jQuery in GWT is that you needed very specific features in jQuery not present in gQuery, although gQuery has almost completed the jQuery API.