void readExternal(Element element) throws InvalidDataException {
    DefaultJDOMExternalizer.readExternal(this, element);
    LOG.assertTrue(mySandboxRoot == null);
    myJavaSdkName = element.getAttributeValue(SDK);
    if (mySandboxHome != null) {
      mySandboxRoot = LocalFileSystem.getInstance().addRootToWatch(mySandboxHome, true);
    }
  }
void readExternal(Element element)