我希望开始使用Usergrid，并按照https://github.com/apache/incubator-usergrid/tree/master/stack
上的步骤操作我到了启动gui发射器的地步。
但是，我无法通过转到http://apigee.github.io/usergrid-portal/?api_url=http://localhost:8080来加载网页，我每次都会收到404.
我做错了什么？
在控制台中我收到以下错误：
2014-12-13 13:12:48,133 ERROR (AWT-EventQueue-0) [org.apache.usergrid.persistence.cassandra.EntityManagerImpl] - Unable to load entity: 00000000-0000-0000-0000-000000000001
java.lang.NullPointerException
at me.prettyprint.hector.api.factory.HFactory.createVirtualKeyspace(HFactory.java:320)
at org.apache.usergrid.persistence.cassandra.CassandraService.getKeyspace(CassandraService.java:261)
at org.apache.usergrid.persistence.cassandra.CassandraService.getApplicationKeyspace(CassandraService.java:274)
at org.apache.usergrid.persistence.cassandra.EntityManagerImpl.getEntityType(EntityManagerImpl.java:996)
at org.apache.usergrid.persistence.cassandra.EntityManagerImpl.getRef(EntityManagerImpl.java:1797)
at org.apache.usergrid.persistence.cassandra.EntityManagerImpl.validate(EntityManagerImpl.java:1757)
at org.apache.usergrid.persistence.cassandra.EntityManagerImpl.validate(EntityManagerImpl.java:1742)
at org.apache.usergrid.persistence.cassandra.RelationManagerImpl.searchCollection(RelationManagerImpl.java:1764)
at org.apache.usergrid.persistence.cassandra.EntityManagerImpl.getUserByIdentifier(EntityManagerImpl.java:1536)
at org.apache.usergrid.persistence.cassandra.EntityManagerImpl$$FastClassByCGLIB$$db0622e.invoke(<generated>)
at net.sf.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
at org.springframework.aop.framework.Cglib2AopProxy$CglibMethodInvocation.invokeJoinpoint(Cglib2AopProxy.java:689)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:90)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.Cglib2AopProxy$DynamicAdvisedInterceptor.intercept(Cglib2AopProxy.java:622)
at org.apache.usergrid.persistence.cassandra.EntityManagerImpl$$EnhancerByCGLIB$$fe4a7dad.getUserByIdentifier(<generated>)
at org.apache.usergrid.management.cassandra.ManagementServiceImpl.getUserEntityByIdentifier(ManagementServiceImpl.java:1035)
at org.apache.usergrid.management.cassandra.ManagementServiceImpl.getAdminUserByEmail(ManagementServiceImpl.java:1028)
at org.apache.usergrid.launcher.Server.getAccessTokenForAdminUser(Server.java:599)
at org.apache.usergrid.launcher.App.getAccessToken(App.java:268)
at org.apache.usergrid.launcher.LauncherFrame.getAdminURI(LauncherFrame.java:384)
at org.apache.usergrid.launcher.LauncherFrame$5.actionPerformed(LauncherFrame.java:211)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
at java.awt.Component.processMouseEvent(Component.java:6516)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3320)
at java.awt.Component.processEvent(Component.java:6281)
at java.awt.Container.processEvent(Container.java:2229)
at java.awt.Component.dispatchEventImpl(Component.java:4872)
at java.awt.Container.dispatchEventImpl(Container.java:2287)
at java.awt.Component.dispatchEvent(Component.java:4698)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4832)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4492)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4422)
at java.awt.Container.dispatchEventImpl(Container.java:2273)
at java.awt.Window.dispatchEventImpl(Window.java:2719)
at java.awt.Component.dispatchEvent(Component.java:4698)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:735)
at java.awt.EventQueue.access$200(EventQueue.java:103)
at java.awt.EventQueue$3.run(EventQueue.java:694)
at java.awt.EventQueue$3.run(EventQueue.java:692)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
at java.awt.EventQueue$4.run(EventQueue.java:708)
at java.awt.EventQueue$4.run(EventQueue.java:706)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:705)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)