UriFragmentUtility导致servlet异常

Question

因为我正在关注如何正确使用UriFragmentUtility这个vaadin：https://vaadin.com/book/-/page/advanced.urifu.html教程，我最终创建了该对象，并在尝试将此组件添加到我的主窗口后失败，并出现以下异常：

SEVERE: Servlet.service() for servlet [Dugsi_Manager Vaadin Application Servlet] in context with path [/Dugsi_Manager] threw exception [java.lang.UnsupportedOperationException] with root cause 
java.lang.UnsupportedOperationException 
    com.vaadin.ui.CustomComponent.addComponent(CustomComponent.java:218) 
    com.vaadin.ui.Panel.addComponent(Panel.java:301) 
    com.vaadin.ui.Window.addComponent(Window.java:281) 
    org.bixin.dugsi.web.DugsiManagerApplication.init(DugsiManagerApplication.java:44) 
    com.vaadin.Application.start(Application.java:554) 
    com.vaadin.terminal.gwt.server.AbstractApplicationServlet.startApplication(AbstractApplicationServlet.java:1213) 
    com.vaadin.terminal.gwt.server.AbstractApplicationServlet.service(AbstractApplicationServlet.java:484) 
    javax.servlet.http.HttpServlet.service(HttpServlet.java:722) 
    org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:359) 
    org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:275) 
    org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90) 
    org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83) 
    org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:344) 
    org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:272) 
    org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:81) 
    org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:237) 
    org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167) 

这里是我添加的对象到我的主应用程序类：

//Thread Local to create instances of our application 
private static ThreadLocal<DugsiManagerApplication> threadLocal = new ThreadLocal<DugsiManagerApplication>(); 
@Override 
public void init() { 
    setInstance(this); // immediate access to the app 
    //Window homeWindow = createNewWindow(); 
    Subject currentUser = SecurityUtils.getSubject(); 
    // Create the URI fragment utility 
    Window window = createLoginWindow();  

    setMainWindow(window); 
    final UriFragmentUtility urifu = new UriFragmentUtility(); 
    window.addComponent(urifu); 

} 

在它谈论的URI初级部分（地址+路径+可选的查询参数）的教程，我的路径设置as/Du gsi_Manager（web.xml）是否应该在将urifu对象作为https://localhost:8080/Dugsi_Manger#login添加后启动？

编辑：增加了登录窗口的声明：

public Window createLoginWindow(){ 
    final Window loginWindow = new LoginWindow(); 

    //remove the window if closed to avoid memory leaks 
    loginWindow.addListener(new CloseListener() { 
     @Override 
     public void windowClose(CloseEvent e) { 
      if (getMainWindow() != loginWindow) { 
       DugsiManagerApplication.this.removeWindow(loginWindow); 
      } 
     } 
    }); 
    return loginWindow; 
} 

\ **这似乎为UriFragmentUtility对象可以被添加到一个标准的Vaadin窗口，但我createLoginWindow函数创建的窗口上不起作用？我无法弄清楚为什么？

Answer 1

CustomComponent的addComponent方法抛出异常。所以我猜CustomComponent是一个窗口的内容。为了解决这个问题，直接添加到UriFragmentUtility这CustomComponent的组成根，而不是

window.addComponent(urifu);