将Java包添加到GWT

package mypackage;

public class MyClass {
    public static String myMethod() {
        return "Hello, GWT!";
    }
}

<inherits name="com.google.gwt.user.User"/>
<inherits name="mypackage.MyClass"/>

import mypackage.MyClass;

public class MyGWTProject {
    public void myMethod() {
        String message = MyClass.myMethod();
        Window.alert(message);
    }
}