GWT2.2 java.lang.RuntimeException: Deferred binding failed for a class (did you forget to inherit a required module?)

Question

I'm using gwt 2.2, and encountered with the below exception: 18:43:48.896 [ERROR] [dms] Failed to create an instance of 'package.DMS' via deferred binding

java.lang.RuntimeException: Deferred binding failed for 'package.client.FileServiceAsync' (did you forget to inherit a required module?)
    at com.google.gwt.dev.shell.GWTBridgeImpl.create(GWTBridgeImpl.java:53)
    at com.google.gwt.core.client.GWT.create(GWT.java:98)
    at person.tanjinfu.dms.client.DMS.<init>(DMS.java:61)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
    at com.google.gwt.dev.shell.ModuleSpace.rebindAndCreate(ModuleSpace.java:465)
    at com.google.gwt.dev.shell.ModuleSpace.onLoad(ModuleSpace.java:375)
    at com.google.gwt.dev.shell.OophmSessionHandler.loadModule(OophmSessionHandler.java:183)
    at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:510)
    at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:352)
    at java.lang.Thread.run(Thread.java:619)
Caused by: com.google.gwt.core.ext.UnableToCompleteException: (see previous log entries)
    at com.google.gwt.dev.shell.ModuleSpace.rebindAndCreate(ModuleSpace.java:503)
    at com.google.gwt.dev.shell.GWTBridgeImpl.create(GWTBridgeImpl.java:49)
    at com.google.gwt.core.client.GWT.create(GWT.java:98)
    at person.tanjinfu.dms.client.DMS.<init>(DMS.java:61)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
    at com.google.gwt.dev.shell.ModuleSpace.rebindAndCreate(ModuleSpace.java:465)
    at com.google.gwt.dev.shell.ModuleSpace.onLoad(ModuleSpace.java:375)
    at com.google.gwt.dev.shell.OophmSessionHandler.loadModule(OophmSessionHandler.java:183)
    at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:510)
    at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:352)
    at java.lang.Thread.run(Thread.java:619)

Is there anybody can help me?