ON jetty 8 to jetty 9 migration when using jetty-maven-plugin, the application cannot load because of the class cast exception:
java.lang.ClassCastException: org.eclipse.jetty.webapp.WebAppContext cannot be cast to org.eclipse.jetty.maven.plugin.JettyWebAppContext
Change the context handler from WebAppContext to JettyWebApp context.
<contextHandlers>
<contextHandler implementation="org.eclipse.jetty.maven.plugin.JettyWebAppContext">
<war>../../flieName.war</war>
<contextPath>/yourPath</contextPath>
</contextHandler>
<contextHandler implementation="org.eclipse.jetty.maven.plugin.JettyWebAppContext">
<war>../../yourWar.war</war>
<contextPath>/anotherPath</contextPath>
</contextHandler>
<contextHandler implementation="org.eclipse.jetty.maven.plugin.JettyWebAppContext">
<war>../../../anotherApp.war</war>
<contextPath>/oneMorePath</contextPath>
</contextHandler>
Also make the same change to your jetty-context.xml
<Configure class="org.eclipse.jetty.maven.plugin.JettyWebAppContext">