code: @Nullable
    public static Templates getXSLTTemplates (@Nonnull final EEbInterfaceVersion eVersion)
    {
      final String sNamespaceURI = eVersion.getNamespaceURI ();
      final Templates ret = s_aRWLock.readLocked ( () -> s_aTemplates.get (sNamespaceURI));
      if (ret != null)
        return ret;
  
      return s_aRWLock.writeLocked ( () -> {
        // Try again in write lock
        Templates ret2 = s_aTemplates.get (sNamespaceURI);
        if (ret2 == null)
        {
          // Definitely not present - init
          final IReadableResource aXSLTRes = eVersion.getXSLTResource ();
          ret2 = XMLTransformerFactory.newTemplates (aXSLTRes);
          if (ret2 == null)
            LOGGER.error ("Failed to parse XSLT template " + aXSLTRes);
          else
            if (LOGGER.isDebugEnabled ())
              LOGGER.debug ("Compiled XSLT template " + aXSLTRes);
          s_aTemplates.put (sNamespaceURI, ret2);
        }
        return ret2;
      });
    }
docs: Get the precompiled XSLT template to be used. It is lazily initialized upon
  first call.
  
  @param eVersion
  The ebInterface version to be used. May not be <code>null</code>.
  @return The XSLT {@link Templates} to be used to visualize invoices or
  <code>null</code> if the template is buggy!