code: @Test public void shouldBeThreadSafe() throws Exception {
    factory=new XmlModelFactory(){
      @Override protected InputStream getModelResourceAsStream(){
        return TestXmlModelFactory.class.getResourceAsStream("testimport/validImports.xml");
      }
    }
  ;
    WroTestUtils.init(factory);
    final WroModel expected=factory.create();
    WroTestUtils.runConcurrently(new ContextPropagatingCallable<Void>(new Callable<Void>(){
      public Void call() throws Exception {
        assertEquals(expected,factory.create());
        return null;
      }
    }
  ),10);
  }
  