Gwt 选择项未填充

我正在填充一个SelectItem。我的服务器调用返回结果，但UI端未填充该结果。我得到以下错误。有人能帮我吗？这一错误背后的原因是什么

WARN:DataSource:isc_CellOptionDataSource_0:one-time fetch failed with status: -90 and messsage: [object Object].  Initializing an empty Array as testData.
com.smartgwt.client.core.JsObject$SGWT_WARN: 10:45:44.814:XRP7:WARN:DataSource:isc_CellOptionDataSource_0:one-time fetch failed with status: -90 and messsage: [object Object].  Initializing an empty Array as testData.
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:105)
    at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
    at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:157)
    at com.google.gwt.dev.shell.BrowserChannel.reactToMessages(BrowserChannel.java:1669)
    at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:401)
    at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:222)
    at java.lang.Thread.run(Unknown Source)