public void add(Injection injection) {
    if ((injection == null) || injection.getTargetClass() == null) return;

    if (LOG.isDebugEnabled())
      LOG.debug(
          "Adding injection for class="
              + (injection.getTargetClass() + " on a " + (injection.getTarget().getName())));

    List<Injection> injections =
        (List<Injection>) _injectionMap.get(injection.getTargetClass().getCanonicalName());
    if (injections == null) {
      injections = new ArrayList<Injection>();
      _injectionMap.put(injection.getTargetClass().getCanonicalName(), injections);
    }
    injections.add(injection);
  }