如何获得类所在的jar文件或目录

   URL confURL = BeansConstants.class.getClassLoader().getResource(XML_CONFIG_FILE);
              if (confURL == null)
                confURL = BeansConstants.class.getClassLoader().getResource("/" + XML_CONFIG_FILE);
              if (confURL == null)
                confURL = Thread.currentThread().getContextClassLoader().getResource(XML_CONFIG_FILE);
<p class="indent">