code: public static CmsTextMetrics get(Element element, String key) {
  
          CmsTextMetrics instance = null;
          if (key == null) {
              instance = new CmsTextMetrics(key);
              instance.bind(element);
          } else {
              instance = m_instances.get(key);
              if (instance == null) {
                  instance = new CmsTextMetrics(key);
                  instance.bind(element);
                  m_instances.put(key, instance);
              }
          }
          return instance;
      }
docs: Gets the text metrics object for a given DOM element and key.<p>
  
  If the key is null, or the method has been never called with the same key
  before, a new text metrics object will be created, with its style taken from
  the element parameter. Otherwise, the text metrics object for the given key will
  be returned, and the element parameter will be ignored.
  
  @param element the element from which to take the style
  @param key the text metrics key
  
  @return a text metrics object