can anyone help me why this exception is occuring.....
javax.servlet.ServletException: Servlet execution threw an exception org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:393)
root cause
java.lang.NoSuchMethodError: com.google.common.collect.ImmutableSet.of([Ljava/lang/Object;)Lcom/google/common/collect/ImmutableSet; com.google.gdata.wireformats.AltFormat$Builder.setAcceptableTypes(AltFormat.java:399) com.google.gdata.wireformats.AltFormat$Builder.setAcceptableXmlTypes(AltFormat.java:387) com.google.gdata.wireformats.AltFormat.<clinit>(AltFormat.java:49) com.google.gdata.client.Service.<clinit>(Service.java:558) com.netelixir.lxr.dailyTracker.services.GoogleServiceCreator.createSpreadSheetService(GoogleServiceCreator.java:22) com.netelixir.lxr.dailyTracker.services.GoogleServiceCreator.getSpreadSheetService(GoogleServiceCreator.java:36) com.netelixir.lxr.dailyTracker.services.SpreadSheetUtil.<init>(SpreadSheetUtil.java:39) com.netelixir.lxr.dailyTracker.DailyTrackerActionForm.validate(DailyTrackerActionForm.java:183) org.apache.struts.action.RequestProcessor.processValidate(RequestProcessor.java:950) org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:198) org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913) org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:462) javax.servlet.http.HttpServlet.service(HttpServlet.java:648) javax.servlet.http.HttpServlet.service(HttpServlet.java:729) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:393)