java.netでエラー

HTTP Status 500 - 
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type Exception report
message 
description The server encountered an internal error () that prevented it from fulfilling this request.
exception 
java.lang.NullPointerException
  org.springframework.orm.hibernate.SessionFactoryUtils.closeSessionOrRegisterDeferredClose(SessionFactoryUtils.java:713)
  org.springframework.orm.hibernate.SessionFactoryUtils.closeSessionIfNecessary(SessionFactoryUtils.java:701)
  org.springframework.orm.hibernate.support.OpenSessionInViewFilter.closeSession(OpenSessionInViewFilter.java:251)
  com.atlassian.spring.filter.FlushingSpringSessionInViewFilter.closeSession(FlushingSpringSessionInViewFilter.java:54)
  org.springframework.orm.hibernate.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:181)
  com.atlassian.spring.filter.FlushingSpringSessionInViewFilter.doFilterInternal(FlushingSpringSessionInViewFilter.java:29)
  org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
  com.atlassian.util.profiling.filters.ProfilingFilter.doFilter(ProfilingFilter.java:122)
  com.atlassian.core.filters.ProfilingAndErrorFilter.doFilter(ProfilingAndErrorFilter.java:27)
  com.atlassian.confluence.util.RequestCacheThreadLocalFilter.doFilter(RequestCacheThreadLocalFilter.java:25)
  com.atlassian.core.filters.gzip.GzipFilter.doFilter(GzipFilter.java:61)
  com.atlassian.core.filters.AbstractEncodingFilter.doFilter(AbstractEncodingFilter.java:37)

note The full stack trace of the root cause is available in the Apache Tomcat/6.0.13 logs.
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Apache Tomcat/6.0.13


Tomcat+Spring+hibernateですか。java.net が重いのはそれが原因なのかなー。