code: public synchronized XAttribute put(String key, XAttribute value) {
  		if(backingStore == null) {
  			try {
  				backingStore = backingStoreClass.newInstance();
  			} catch (Exception e) {
  				// Fuckup
  				e.printStackTrace();
  			}
  		}
  		return backingStore.put(key, value);
  	}
docs: /* (non-Javadoc)
  @see java.util.Map#put(java.lang.Object, java.lang.Object)