This needs some investigation after 601189. Right now this should only go into master if a fix is also required for 601189

Additional Info:

There are no saved searches when the exception is observed.

This error indicates that the subject reference was null.  In theory, if the user is not logged in (subject==null) then they should get the login box.  Did you perhaps walk away from the browser for 15-20 minutes, and then come back and ask for suggestions?  If so, you might have been logged out.

Can you remember any other reproduction steps?

Reproduced this error again with following steps:

1. Login to jon.
2. Navigate to 'Resources->All Resources'.
3. Entered in searchbar: plugin=apache
4. Pressed Enter key.
5. It displayed the search results.
6. Entered space and entered in searchbar:  type=
7. Observed the message in browser: "Error retrieving suggestions: null, see server log for more details" in searchbar.
8. Serverlog displayed NullPointerException.

Please refer the screenshot attached. This error is observed in continued operation with browser.(I was not away from browser). However, this is intermittent. Not reproduced again with the same steps.
 

Below is the stack trace:

2010-06-08 15:48:37,113 INFO  [org.rhq.enterprise.server.search.execution.SearchAssistManager] Error retrieving suggestions
java.lang.NullPointerException
        at org.rhq.enterprise.server.search.execution.SearchAssistManager.getUserSavedSearchSuggestions(SearchAssistManager.java:553)
        at org.rhq.enterprise.server.search.execution.SearchAssistManager.getSuggestions(SearchAssistManager.java:368)
        at org.rhq.enterprise.gui.coregui.server.gwt.SearchGWTServiceImpl.getSuggestions(SearchGWTServiceImpl.java:43)
        at sun.reflect.GeneratedMethodAccessor561.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at com.google.gwt.user.server.rpc.RPC.invokeAndEncodeResponse(RPC.java:562)
        at com.google.gwt.user.server.rpc.RemoteServiceServlet.processCall(RemoteServiceServlet.java:188)
        at com.google.gwt.user.server.rpc.RemoteServiceServlet.processPost(RemoteServiceServlet.java:224)
        at com.google.gwt.user.server.rpc.AbstractRemoteServiceServlet.doPost(AbstractRemoteServiceServlet.java:62)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
        at org.rhq.enterprise.gui.coregui.server.gwt.AbstractGWTServiceImpl.service(AbstractGWTServiceImpl.java:61)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
        at org.rhq.helpers.rtfilter.filter.RtFilter.doFilter(RtFilter.java:124)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
        at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:230)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
        at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:182)
        at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:84)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
        at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:157)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:262)
        at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
        at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
        at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:446)
        at java.lang.Thread.run(Thread.java:619)

Created attachment 422142 [details]
Screenshot for error message in searchbar

commit 5705abb4352b142bfe840c0dc55e6d02d82de761
Author: Joseph Marques <joseph>
Date:   Thu Jun 24 18:22:40 2010 -0400

    BZ-601240: more graceful handling of exceptional conditions when loading SearchSuggestions

Verified on JON 2.4 GA_QA build#43

The NullPointerException is not observed in server log while testing search.

Mass-closure of verified bugs against JON.