apache-flex - faultString = "java.lang.NullPointerException：空"

Question

几天来我一直在拉头发，试图找出错误。我有一个带有本地安装的 tomcat 和一个 java 后端的 flex 前端。当我单击按钮执行某些操作时，我在下面收到此错误消息

(mx.rpc::Fault)#0
  content = (null)
  errorID = 0
  faultCode = "Server.Processing"
  faultDetail = (null)
  faultString = "java.lang.NullPointerException : null"
  message = "faultCode:Server.Processing faultString:'java.lang.NullPointerException : null' faultDetail:'null'"
  name = "Error"
  rootCause = (Object)#1
    cause = (null)
    localizedMessage = (null)
    message = (null)
    suppressed = (Array)#2

关于从这里去哪里的任何提示？我试过“google-ing”无济于事谢谢