The resource did not process correctly

java.lang.NullPointerException
	at it.mediaus.medealer.controller.ChangeLanguage.processRequest(ChangeLanguage.java:52)
	at it.mediaus.medealer.controller.ChangeLanguage.doGet(ChangeLanguage.java:83)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
	at it.mediaus.medealer.filter.LanguageFilter.doFilter(LanguageFilter.java:122)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
	at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:541)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
	at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:199)
	at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:282)
	at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:754)
	at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:684)
	at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:876)
	at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
	at java.lang.Thread.run(Unknown Source)