/** Test getCommonNamespace(). */
  public void testGetCommonNamespace() {
    StringNamespace sns1 =
        new StringNamespace(new String[] {"org", "argouml", "model"}, Namespace.UML_NS_TOKEN);

    StringNamespace sns2 =
        new StringNamespace(new String[] {"org", "argouml", "model"}, Namespace.UML_NS_TOKEN);

    StringNamespace result = (StringNamespace) sns1.getCommonNamespace(sns2);
    assertEquals("org::argouml::model", result.toString());

    sns1.popNamespaceElement();
    result = (StringNamespace) sns1.getCommonNamespace(sns2);
    assertEquals("org::argouml", result.toString());

    sns1.popNamespaceElement();
    result = (StringNamespace) sns1.getCommonNamespace(sns2);
    assertEquals("org", result.toString());

    sns1.popNamespaceElement();
    result = (StringNamespace) sns1.getCommonNamespace(sns2);
    assertEquals("", result.toString());
  }