sonar启动，后台报错如下：
ERROR jruby.rack - Error: application initialization failed
org.jruby.rack.RackInitializationException: java.lang.NullPointerException: null
from org/sonar/server/ui/JRubyFacade.java:447:in `getServerHome'
from /usr/local/tomcat/temp/0-sonar/WEB-INF/config/environment.rb:52:in `(root)'
from /usr/local/tomcat/temp/0-sonar/WEB-INF/gems/gems/rails- 2.3.14/lib/initializer.rb:111:in `run'
from /usr/local/tomcat/temp/0-sonar/WEB-INF/config/environment.rb:32:in `(root)'
from org/jruby/RubyKernel.java:1058:in `load'
from /usr/local/tomcat/temp/0-sonar/WEB-INF/config/environment.rb:23:in `load_environment'
from /usr/local/java/apache-tomcat- 7.0.23/work/Catalina/localhost/sonar/loader/jruby/rack/rails_booter.rb:65:in `load_environment'
from <script>:1:in `(root)'
at org.jruby.rack.DefaultRackApplicationFactory$4.init (DefaultRackApplicationFactory.java:231) ~[jruby-rack-1.1.10.jar:na]
at org.jruby.rack.DefaultRackApplicationFactory.getApplication (DefaultRackApplicationFactory.java:58) ~[jruby-rack-1.1.10.jar:na]
at org.jruby.rack.SharedRackApplicationFactory.init (SharedRackApplicationFactory.java:33) ~[jruby-rack-1.1.10.jar:na]
at org.jruby.rack.RackServletContextListener.contextInitialized (RackServletContextListener.java:48) ~[jruby-rack-1.1.10.jar:na]
at org.apache.catalina.core.StandardContext.listenerStart (StandardContext.java:4765) [catalina.jar:7.0.23]
at org.apache.catalina.core.StandardContext.startInternal (StandardContext.java:5260) [catalina.jar:7.0.23]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) [catalina.jar:7.0.23]
at org.apache.catalina.core.ContainerBase.addChildInternal (ContainerBase.java:866) [catalina.jar:7.0.23]
at org.apache.catalina.core.ContainerBase.addChild (ContainerBase.java:842) [catalina.jar:7.0.23]
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:615) [catalina.jar:7.0.23]
at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:958) [catalina.jar:7.0.23]
at org.apache.catalina.startup.HostConfig$DeployWar.run (HostConfig.java:1599) [catalina.jar:7.0.23]
at java.util.concurrent.Executors$RunnableAdapter.call (Executors.java:441) [na:1.6.0_35]
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) [na:1.6.0_35]
at java.util.concurrent.FutureTask.run(FutureTask.java:138) [na:1.6.0_35]
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask (ThreadPoolExecutor.java:886) [na:1.6.0_35]
at java.util.concurrent.ThreadPoolExecutor$Worker.run (ThreadPoolExecutor.java:908) [na:1.6.0_35]
at java.lang.Thread.run(Thread.java:680) [na:1.6.0_35]
org.jruby.exceptions.RaiseException: Native Exception: 'class java.lang.NullPointerException'; Message: null; StackTrace: java.lang.NullPointerException
at org.sonar.server.ui.JRubyFacade.get(JRubyFacade.java:84)
at org.sonar.server.ui.JRubyFacade.getServerHome(JRubyFacade.java:447)
at org.sonar.server.ui.JRubyFacade.get(JRubyFacade.java:84) ~ [JRubyFacade.class:na]
at org.sonar.server.ui.JRubyFacade.getServerHome(JRubyFacade.java:447) ~[JRubyFacade.class:na]
Caused by: java.lang.NullPointerException: null
... 2 common frames omitted