NPE at com.atlassian.plugin.DefaultPluginManager.getEnabledModuleDescriptorsByClass(DefaultPluginManager.java:495)

Should we check the plugins.values() for NULL ? And only then set up the iterator. Instead of just assuming that it contains something? And provide a friendly user message?
Associated CSPs : CSP-4802, CSP-4307, CSP-2907

public List getEnabledModuleDescriptorsByClass(Class descriptorClazz)
{
List result = new LinkedList();

for (Iterator iterator = plugins.values().iterator(); iterator.hasNext()
{
Plugin plugin = (Plugin) iterator.next();

----------------------------------------------------------------------------------------------------
Cause:
java.lang.NullPointerException
at com.atlassian.plugin.DefaultPluginManager.getEnabledModuleDescriptorsByClass(DefaultPluginManager.java:495)

Stack Trace: [hide]

java.lang.NullPointerException
at com.atlassian.plugin.DefaultPluginManager.getEnabledModuleDescriptorsByClass(DefaultPluginManager.java:495)
at com.atlassian.confluence.setup.webwork.ConfluenceVelocityContext.addContainerComponents(ConfluenceVelocityContext.java:116)
at com.atlassian.confluence.setup.webwork.ConfluenceVelocityContext.addSpringComponentsIfSetupComplete(ConfluenceVelocityContext.java:99)
at com.atlassian.confluence.setup.webwork.ConfluenceVelocityContext.(ConfluenceVelocityContext.java:65)
at com.atlassian.confluence.util.profiling.ProfilingPageFilter.applyDecoratorUsingVelocity(ProfilingPageFilter.java:86)
at com.atlassian.confluence.util.profiling.ProfilingPageFilter.applyDecorator(ProfilingPageFilter.java:67)
at com.opensymphony.module.sitemesh.filter.PageFilter.doFilter(PageFilter.java:59)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.confluence.util.ServletContextThreadLocalFilter.doFilter(ServletContextThreadLocalFilter.java:30)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.confluence.util.UserThreadLocalFilter.doFilter(UserThreadLocalFilter.java:45)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.seraph.filter.SecurityFilter.doFilter(SecurityFilter.java:83)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.seraph.filter.LoginFilter.doFilter(LoginFilter.java:92)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.johnson.filters.JohnsonFilter.doFilter(JohnsonFilter.java:96)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at org.springframework.orm.hibernate.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:170)
at bucket.custom.FlushingSpringSessionInViewFilter.doFilterInternal(FlushingSpringSessionInViewFilter.java:31)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:73)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.util.profiling.filters.ProfilingFilter.doFilter(ProfilingFilter.java:122)
at com.atlassian.confluence.util.error.ProfilingAndErrorFilter.doFilter(ProfilingAndErrorFilter.java:27)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.core.filters.gzip.GzipFilter.doFilter(GzipFilter.java:61)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.core.filters.AbstractEncodingFilter.doFilter(AbstractEncodingFilter.java:37)
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.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:667)
at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
at java.lang.Thread.run(Thread.java:595)

Referer URL: http://localhost:8888/setup/dosetuplicense.action

Build Information:
Confluence Home: C:\confluence\data
Uptime: 2 minutes, 42 seconds
Version: 2.2.6a
Build Number: 522

Server Information:
Application Server: Apache Tomcat/5.5.15
Servlet Version: 2.4
Database Dialect: net.sf.hibernate.dialect.HSQLDialect
Database Driver Name: org.hsqldb.jdbcDriver
Database Driver Version: 1.8

Memory Information:
Total Memory: 127 MB
Free Memory: 76 MB
Used Memory: 51 MB

System Information:
System Date: Dienstag, 08 Aug 2006
System Time: 13:55:44
System Favourite Colour: Taupe
Java Version: 1.5.0_06
Java Vendor: Sun Microsystems Inc.
JVM Version: 1.0
JVM Vendor: Sun Microsystems Inc.
JVM Implementation Version: 1.5.0_06-b05
Java Runtime: Java(TM) 2 Runtime Environment, Standard Edition
Java VM: Java HotSpot(TM) Client VM
User Name: Administrator
User Timezone: Europe/Berlin
Operating System: Windows 2003 5.2
OS Architecture: x86
Filesystem Encoding: Cp1252

Enabled Plugins:
Couldn't report plugins:java.lang.NullPointerException

Request
Information:
URL: http://localhost:8888/500page.jsp

• Scheme: http
• Server: localhost
• Port: 8888
• URI: /500page.jsp
• - Context Path:
• - Servlet Path: /500page.jsp
• - Path Info: null
• - Query String: null

Attributes:

• javax.servlet.forward.request_uri : /setup/setupdbchoice-start.action
• javax.servlet.forward.context_path :
• javax.servlet.forward.servlet_path : /setup/setupdbchoice-start.action
• javax.servlet.forward.path_info : /500page.jsp
• javax.servlet.error.servlet_name : action
• javax.servlet.error.message :
• javax.servlet.error.exception : java.lang.NullPointerException
• webwork.valueStack : com.opensymphony.xwork.util.OgnlValueStack@f0269d
• _sitemesh_using_stream : false
• com.atlassian.johnson.filters.JohnsonFilter_already_filtered : true
• javax.servlet.error.request_uri : /setup/setupdbchoice-start.action
• javax.servlet.error.status_code : 500
• _sitemesh_page : com.opensymphony.module.sitemesh.parser.FastPage@7732d4
• _sitemesh_filterapplied : true
• sessioninview.FILTERED : true
• com.atlassian.core.filters.gzip.GzipFilter_already_filtered : true

Parameters:
Confluence User:

• anonymous

Logging:
0 log statements generated by this request.