該bug發生的第一種情況是：

This means that more than one application is started in the same context and in the same HttpService. When different applications run in the same HttpService, they have to use different context paths.

This also happens when an ApplicationConfiguration is registered AND the org.eclipse.rap.workbench bundle is running (seebug 377414).

To register anApplicationConfigurationon a custom context using declarative services, add the following line to the service component definition:

  <PRoperty name="contextName" type="String" value="example"/>

See alsoApplicationLauncher#PROPERTY_CONTEXT_NAME.

https://wiki.eclipse.org/RAP/FAQ#NamespaceException:_The_alias_.27.2Frwt-resources.27_is_already_in_use

　　意思就是RAP運行在容器中的，但是你一個容器不弄同時跑兩個RAP應用，主要是一個應用，多個bundle的情況會發生這種問題。

　　補充描述告訴我們一個容器中Application的處理方式“ApplicationConfigurationon a custom context using declarative services”，那就好辦了，我們找到容器中定義service的地方，把service去掉就行了

　　方案：找到MANIFEST.MF去掉contribution.xml(services定義在這)的加載；

　　第二種情況：

　　新插件（bundle）加載的沖突，如果希望用e4里邊的控件的話，問題可能就在這bundle里面，解決方案還是得求老外ㄒoㄒ：

this is because bothorg.eclipse.e4.ui.workbench and org.eclipse.rap.ui.workbench exists. Youshould remove the org.eclipse.rap.ui.workbench.

http://www.postseek.com/meta/2f8c97b62bcde5119f8225d93db3bc1d

　　eclipse bug 庫里面也確定了這個bug：https://bugs.eclipse.org/bugs/show_bug.cgi?id=369657