Element child1b = factory.element("child1b");
Element child2b = factory.element("child2b");
parent2.addContent(child1b);
parent2.addContent(child2b);
Element root = factory.element("root");
root.addContent(parent2);
root.addContent(parent1);
ElementChildrenTreeContentProvider provider =
new ElementChildrenTreeContentProvider(null, null, true, false);