title: cannot get connection: general error
body: <p>Following is a stack trace that I am dealing with.</p>
  
  <pre><code>2015-04-04 19:15:55,322 [qtp425995691-3536] WARN  org.hibernate.util.JDBCExceptionReporter - SQL Error: 0, SQLState: null
  2015-04-04 19:15:55,322 [qtp425995691-3536] ERROR org.hibernate.util.JDBCExceptionReporter - Cannot get a connection, general error
  2015-04-04 19:15:55.323:WARN:oejs.ServletHandler:/accounts/api/login
  org.hibernate.exception.GenericJDBCException: Cannot open connection
      at org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:140)
      at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:128)
      at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
      at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:52)
      at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:449)
      at org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:167)
      at org.hibernate.jdbc.AbstractBatcher.prepareQueryStatement(AbstractBatcher.java:161)
      at org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:1616)
      at org.hibernate.loader.Loader.doQuery(Loader.java:717)
      at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:270)
      at org.hibernate.loader.Loader.loadCollection(Loader.java:2082)
      at org.hibernate.loader.collection.CollectionLoader.initialize(CollectionLoader.java:62)
      at org.hibernate.persister.collection.AbstractCollectionPersister.initialize(AbstractCollectionPersister.java:628)
      at org.hibernate.event.def.DefaultInitializeCollectionEventListener.onInitializeCollection(DefaultInitializeCollectionEventListener.java:83)
      at org.hibernate.impl.SessionImpl.initializeCollection(SessionImpl.java:1853)
      at org.hibernate.collection.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:369)
      at org.hibernate.collection.AbstractPersistentCollection.read(AbstractPersistentCollection.java:111)
      at org.hibernate.collection.PersistentSet.iterator(PersistentSet.java:186)
      at com.nim.domain.user.UserDetail.getAuthorities(UserDetail.java:379)
      at org.springframework.security.authentication.dao.AbstractUserDetailsAuthenticationProvider.createSuccessAuthentication(AbstractUserDetailsAuthenticationProvider.java:186)
      at org.springframework.security.authentication.dao.AbstractUserDetailsAuthenticationProvider.authenticate(AbstractUserDetailsAuthenticationProvider.java:165)
      at org.springframework.security.authentication.ProviderManager.doAuthentication(ProviderManager.java:120)
      at org.springframework.security.authentication.AbstractAuthenticationManager.authenticate(AbstractAuthenticationManager.java:48)
      at org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter.attemptAuthentication(UsernamePasswordAuthenticationFilter.java:97)
      at com.nim.store.security.NIMAuthenticationProcessingFilter.attemptAuthentication(NIMAuthenticationProcessingFilter.java:69)
      at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:200)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:355)
      at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:355)
      at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:79)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:355)
      at org.springframework.security.web.session.ConcurrentSessionFilter.doFilter(ConcurrentSessionFilter.java:109)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:355)
      at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:149)
      at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)
      at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:259)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77)
      at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter.doFilterInternal(OpenEntityManagerInViewFilter.java:147)
      at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.eclipse.jetty.servlets.UserAgentFilter.doFilter(UserAgentFilter.java:82)
      at org.eclipse.jetty.servlets.GzipFilter.doFilter(GzipFilter.java:263)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at com.nim.store.filter.CacheFilter.doFilter(CacheFilter.java:25)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.eclipse.jetty.servlets.CrossOriginFilter.handle(CrossOriginFilter.java:247)
      at org.eclipse.jetty.servlets.CrossOriginFilter.doFilter(CrossOriginFilter.java:210)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.eclipse.jetty.servlets.DoSFilter.doFilterChain(DoSFilter.java:484)
      at org.eclipse.jetty.servlets.DoSFilter.doFilter(DoSFilter.java:332)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:453)
      at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:137)
      at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:559)
      at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:231)
      at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1072)
      at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:382)
      at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:193)
      at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1006)
      at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:135)
      at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:255)
      at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:154)
      at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:116)
      at org.eclipse.jetty.server.Server.handle(Server.java:365)
      at org.eclipse.jetty.server.AbstractHttpConnection.handleRequest(AbstractHttpConnection.java:485)
      at org.eclipse.jetty.server.AbstractHttpConnection.headerComplete(AbstractHttpConnection.java:926)
      at org.eclipse.jetty.server.AbstractHttpConnection$RequestHandler.headerComplete(AbstractHttpConnection.java:988)
      at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:642)
      at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:235)
      at org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:82)
      at org.eclipse.jetty.io.nio.SslConnection.handle(SslConnection.java:196)
      at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:627)
      at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:51)
      at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:608)
      at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:543)
      at java.lang.Thread.run(Thread.java:722)
  Caused by: 
  org.apache.commons.dbcp.SQLNestedException: Cannot get a connection, general error
      at org.apache.commons.dbcp.PoolingDataSource.getConnection(PoolingDataSource.java:118)
      at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044)
      at org.hibernate.ejb.connection.InjectedDataSourceConnectionProvider.getConnection(InjectedDataSourceConnectionProvider.java:71)
      at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:446)
      at org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:167)
      at org.hibernate.jdbc.AbstractBatcher.prepareQueryStatement(AbstractBatcher.java:161)
      at org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:1616)
      at org.hibernate.loader.Loader.doQuery(Loader.java:717)
      at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:270)
      at org.hibernate.loader.Loader.loadCollection(Loader.java:2082)
      at org.hibernate.loader.collection.CollectionLoader.initialize(CollectionLoader.java:62)
      at org.hibernate.persister.collection.AbstractCollectionPersister.initialize(AbstractCollectionPersister.java:628)
      at org.hibernate.event.def.DefaultInitializeCollectionEventListener.onInitializeCollection(DefaultInitializeCollectionEventListener.java:83)
      at org.hibernate.impl.SessionImpl.initializeCollection(SessionImpl.java:1853)
      at org.hibernate.collection.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:369)
      at org.hibernate.collection.AbstractPersistentCollection.read(AbstractPersistentCollection.java:111)
      at org.hibernate.collection.PersistentSet.iterator(PersistentSet.java:186)
      at com.nim.domain.user.UserDetail.getAuthorities(UserDetail.java:379)
      at org.springframework.security.authentication.dao.AbstractUserDetailsAuthenticationProvider.createSuccessAuthentication(AbstractUserDetailsAuthenticationProvider.java:186)
      at org.springframework.security.authentication.dao.AbstractUserDetailsAuthenticationProvider.authenticate(AbstractUserDetailsAuthenticationProvider.java:165)
      at org.springframework.security.authentication.ProviderManager.doAuthentication(ProviderManager.java:120)
      at org.springframework.security.authentication.AbstractAuthenticationManager.authenticate(AbstractAuthenticationManager.java:48)
      at org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter.attemptAuthentication(UsernamePasswordAuthenticationFilter.java:97)
      at com.nim.store.security.NIMAuthenticationProcessingFilter.attemptAuthentication(NIMAuthenticationProcessingFilter.java:69)
      at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:200)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:355)
      at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:355)
      at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:79)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:355)
      at org.springframework.security.web.session.ConcurrentSessionFilter.doFilter(ConcurrentSessionFilter.java:109)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:355)
      at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:149)
      at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)
      at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:259)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77)
      at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter.doFilterInternal(OpenEntityManagerInViewFilter.java:147)
      at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.eclipse.jetty.servlets.UserAgentFilter.doFilter(UserAgentFilter.java:82)
      at org.eclipse.jetty.servlets.GzipFilter.doFilter(GzipFilter.java:263)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at com.nim.store.filter.CacheFilter.doFilter(CacheFilter.java:25)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.eclipse.jetty.servlets.CrossOriginFilter.handle(CrossOriginFilter.java:247)
      at org.eclipse.jetty.servlets.CrossOriginFilter.doFilter(CrossOriginFilter.java:210)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.eclipse.jetty.servlets.DoSFilter.doFilterChain(DoSFilter.java:484)
      at org.eclipse.jetty.servlets.DoSFilter.doFilter(DoSFilter.java:332)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:453)
      at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:137)
      at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:559)
      at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:231)
      at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1072)
      at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:382)
      at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:193)
      at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1006)
      at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:135)
      at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:255)
      at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:154)
      at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:116)
      at org.eclipse.jetty.server.Server.handle(Server.java:365)
      at org.eclipse.jetty.server.AbstractHttpConnection.handleRequest(AbstractHttpConnection.java:485)
      at org.eclipse.jetty.server.AbstractHttpConnection.headerComplete(AbstractHttpConnection.java:926)
      at org.eclipse.jetty.server.AbstractHttpConnection$RequestHandler.headerComplete(AbstractHttpConnection.java:988)
      at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:642)
      at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:235)
      at org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:82)
      at org.eclipse.jetty.io.nio.SslConnection.handle(SslConnection.java:196)
      at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:627)
      at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:51)
      at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:608)
      at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:543)
      at java.lang.Thread.run(Thread.java:722)
  Caused by: 
  java.lang.InterruptedException
      at java.lang.Object.wait(Native Method)
      at java.lang.Object.wait(Object.java:503)
      at org.apache.commons.pool.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:1104)
      at org.apache.commons.dbcp.PoolingDataSource.getConnection(PoolingDataSource.java:106)
      at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044)
      at org.hibernate.ejb.connection.InjectedDataSourceConnectionProvider.getConnection(InjectedDataSourceConnectionProvider.java:71)
      at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:446)
      at org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:167)
      at org.hibernate.jdbc.AbstractBatcher.prepareQueryStatement(AbstractBatcher.java:161)
      at org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:1616)
      at org.hibernate.loader.Loader.doQuery(Loader.java:717)
      at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:270)
      at org.hibernate.loader.Loader.loadCollection(Loader.java:2082)
      at org.hibernate.loader.collection.CollectionLoader.initialize(CollectionLoader.java:62)
      at org.hibernate.persister.collection.AbstractCollectionPersister.initialize(AbstractCollectionPersister.java:628)
      at org.hibernate.event.def.DefaultInitializeCollectionEventListener.onInitializeCollection(DefaultInitializeCollectionEventListener.java:83)
      at org.hibernate.impl.SessionImpl.initializeCollection(SessionImpl.java:1853)
      at org.hibernate.collection.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:369)
      at org.hibernate.collection.AbstractPersistentCollection.read(AbstractPersistentCollection.java:111)
      at org.hibernate.collection.PersistentSet.iterator(PersistentSet.java:186)
      at com.nim.domain.user.UserDetail.getAuthorities(UserDetail.java:379)
      at org.springframework.security.authentication.dao.AbstractUserDetailsAuthenticationProvider.createSuccessAuthentication(AbstractUserDetailsAuthenticationProvider.java:186)
      at org.springframework.security.authentication.dao.AbstractUserDetailsAuthenticationProvider.authenticate(AbstractUserDetailsAuthenticationProvider.java:165)
      at org.springframework.security.authentication.ProviderManager.doAuthentication(ProviderManager.java:120)
      at org.springframework.security.authentication.AbstractAuthenticationManager.authenticate(AbstractAuthenticationManager.java:48)
      at org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter.attemptAuthentication(UsernamePasswordAuthenticationFilter.java:97)
      at com.nim.store.security.NIMAuthenticationProcessingFilter.attemptAuthentication(NIMAuthenticationProcessingFilter.java:69)
      at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:200)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:355)
      at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:355)
      at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:79)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:355)
      at org.springframework.security.web.session.ConcurrentSessionFilter.doFilter(ConcurrentSessionFilter.java:109)
      at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:355)
      at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:149)
      at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)
      at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:259)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77)
      at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter.doFilterInternal(OpenEntityManagerInViewFilter.java:147)
      at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.eclipse.jetty.servlets.UserAgentFilter.doFilter(UserAgentFilter.java:82)
      at org.eclipse.jetty.servlets.GzipFilter.doFilter(GzipFilter.java:263)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at com.nim.store.filter.CacheFilter.doFilter(CacheFilter.java:25)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.eclipse.jetty.servlets.CrossOriginFilter.handle(CrossOriginFilter.java:247)
      at org.eclipse.jetty.servlets.CrossOriginFilter.doFilter(CrossOriginFilter.java:210)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.eclipse.jetty.servlets.DoSFilter.doFilterChain(DoSFilter.java:484)
      at org.eclipse.jetty.servlets.DoSFilter.doFilter(DoSFilter.java:332)
      at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1307)
      at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:453)
      at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:137)
      at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:559)
      at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:231)
      at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1072)
      at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:382)
      at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:193)
      at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1006)
      at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:135)
      at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:255)
      at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:154)
      at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:116)
      at org.eclipse.jetty.server.Server.handle(Server.java:365)
      at org.eclipse.jetty.server.AbstractHttpConnection.handleRequest(AbstractHttpConnection.java:485)
      at org.eclipse.jetty.server.AbstractHttpConnection.headerComplete(AbstractHttpConnection.java:926)
      at org.eclipse.jetty.server.AbstractHttpConnection$RequestHandler.headerComplete(AbstractHttpConnection.java:988)
      at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:642)
      at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:235)
      at org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:82)
      at org.eclipse.jetty.io.nio.SslConnection.handle(SslConnection.java:196)
      at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:627)
      at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:51)
      at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:608)
      at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:543)
      at java.lang.Thread.run(Thread.java:722)
  </code></pre>
  
  <p>What can cause this error?</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>Please note that this stack trace is not consistent. This only happens intermittently.</p>