我是一名学生，我在为考试做一个spring boot应用程序。我已经创建了实体、存储库、服务和控制器，就像在课堂上看到的那样。然而，当我尝试启动我的应用程序时，我得到一个关于嵌入式tomcat的错误。
我正在附加堆栈跟踪：

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2021-06-08 08:59:40.768 ERROR 42228 --- [  restartedMain] o.s.boot.SpringApplication               : Application run failed

org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:163) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:577) ~[spring-context-5.3.7.jar:5.3.7]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:145) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:758) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:438) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:337) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1336) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1325) ~[spring-boot-2.5.0.jar:2.5.0]
    at com.example.fast_food.FastFoodApplication.main(FastFoodApplication.java:12) ~[classes/:na]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64) ~[na:na]
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
    at java.base/java.lang.reflect.Method.invoke(Method.java:564) ~[na:na]
    at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) ~[spring-boot-devtools-2.5.0.jar:2.5.0]
Caused by: org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat
    at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:142) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.<init>(TomcatWebServer.java:104) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getTomcatWebServer(TomcatServletWebServerFactory.java:450) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getWebServer(TomcatServletWebServerFactory.java:199) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:182) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:160) ~[spring-boot-2.5.0.jar:2.5.0]
    ... 13 common frames omitted
Caused by: java.lang.IllegalStateException: StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[] failed to start
    at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.rethrowDeferredStartupExceptions(TomcatWebServer.java:187) ~[spring-boot-2.5.0.jar:2.5.0]
    at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:126) ~[spring-boot-2.5.0.jar:2.5.0]
    ... 18 common frames omitted

Process finished with exit code 0