tomcat 异常：Exception in thread “Timer-0“ java.lang.IllegalStateException: This operation is per...

线程“Timer-O”中的异常java.langllegalStateException：此操作是仅允许事件线程

Exception in thread "Timer-0" java.lang.IllegalStateException: This operation is permitted on the event thread only; currentThread = Timer-0
    at com.sun.glass.ui.Application.checkEventThread(Unknown Source)
    at com.sun.glass.ui.Window.setTitle(Unknown Source)
    at com.sun.javafx.tk.quantum.WindowStage.setTitle(Unknown Source)
    at javafx.stage.Stage$5.invalidated(Unknown Source)
    at javafx.beans.property.StringPropertybase.markInvalid(Unknown Source)
    at javafx.beans.property.StringPropertybase.set(Unknown Source)
    at javafx.beans.property.StringPropertybase.set(Unknown Source)
    at javafx.stage.Stage.setTitle(Unknown Source)
    at Program5$6$1.run(Program5.java:197)
    at java.util.TimerThread.mainLoop(Unknown Source)
    at java.util.TimerThread.run(Unknown Source)

解决办法：

在 tomcat 路径下找到workCatalinalocalhost

→→ 删除对应的 文件（如果找不到具体文件可删除 localhoost 目录下的所有文件）→→  重启项目就解决了。