Before the Java SE 9 release, the DOM API package in `org.w3c.dom` included sub-packages that were not defined as a part of the Jave SE API. As of Java SE 9, these sub-packages are moved out of the `java.xml` module to a separate module called `jdk.xml.dom`. These packages are as follows:
```
    org.w3c.dom.css
    org.w3c.dom.html
    org.w3c.dom.stylesheets
    org.w3c.dom.xpath
```