gwt - webappcreator が実行されないのはなぜですか?

Question

私はWindowsでここの指示に従って実行しています: https://developers.google.com/web-toolkit/gettingstarted

$ ./webAppCreator -out MyWebApp com.mycompany.mywebapp.MyWebApp
java.lang.NoClassDefFoundError: com/google/gwt/user/tools/WebAppCreator
Caused by: java.lang.ClassNotFoundException: com.google.gwt.user.tools.WebAppCreator
        at java.net.URLClassLoader$1.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
Could not find the main class: com.google.gwt.user.tools.WebAppCreator.  Program will exit.
Exception in thread "main"