与 Vaadin 的项目无法启动

Question

I am working on a school project that uses Vaadin, but unfortunately I can't seem to run any project that uses Vaadin. Even when attempting to start the minimal Vaadin project from the official Vaadin site, I still get the same error.

After running the command mvn spring-boot:run , I get the following error:

[INFO] Scanning for projects...
[INFO] 
[INFO] ------------------------< com.example:my-todo >-------------------------
[INFO] Building My Todo 1.0-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
[INFO] 
[INFO] >>> spring-boot-maven-plugin:2.2.0.RELEASE:run (default-cli) > test-compile @ my-todo >>>
[INFO] 
[INFO] --- maven-resources-plugin:3.1.0:resources (default-resources) @ my-todo ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 1 resource
[INFO] Copying 2 resources
[INFO] 
[INFO] --- vaadin-maven-plugin:14.1.25:prepare-frontend (default) @ my-todo ---
[INFO] Copying frontend resources from jar files ...
[INFO] Visited 98 resources. Took 448 ms.
[INFO] 
[INFO] --- maven-compiler-plugin:3.8.1:compile (default-compile) @ my-todo ---
[INFO] Nothing to compile - all classes are up to date
[INFO] 
[INFO] --- maven-resources-plugin:3.1.0:testResources (default-testResources) @ my-todo ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] skip non existing resourceDirectory C:\Users\Matěj\Desktop\my-todo\src\test\resources
[INFO] 
[INFO] --- maven-compiler-plugin:3.8.1:testCompile (default-testCompile) @ my-todo ---
[INFO] Nothing to compile - all classes are up to date
[INFO] 
[INFO] <<< spring-boot-maven-plugin:2.2.0.RELEASE:run (default-cli) < test-compile @ my-todo <<<
[INFO] 
[INFO] 
[INFO] --- spring-boot-maven-plugin:2.2.0.RELEASE:run (default-cli) @ my-todo ---
[INFO] Attaching agents: []
 __  __          _____             _        
|  \/  | _   _  |_   _|  ___    __| |  ___  
| |\/| || | | |   | |   / _ \  / _` | / _ \ 
| |  | || |_| |   | |  | (_) || (_| || (_) |
|_|  |_| \__, |   |_|   \___/  \__,_| \___/ 
         |___/                              

2020-04-27 15:06:26.870  INFO 1872 --- [  restartedMain] com.example.Application                  : Starting Application on ThinkPad-T430 with PID 1872 (started by Matěj in C:\Users\Matěj\Desktop\my-todo)
2020-04-27 15:06:26.876  INFO 1872 --- [  restartedMain] com.example.Application                  : No active profile set, falling back to default profiles: default
2020-04-27 15:06:26.954  INFO 1872 --- [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : Devtools property defaults active! Set 'spring.devtools.add-properties' to 'false' to disable
2020-04-27 15:06:26.954  INFO 1872 --- [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : For additional web related logging consider setting the 'logging.level.web' property to 'DEBUG'
2020-04-27 15:06:28.243  INFO 1872 --- [  restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8080 (http)
2020-04-27 15:06:28.257  INFO 1872 --- [  restartedMain] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2020-04-27 15:06:28.257  INFO 1872 --- [  restartedMain] org.apache.catalina.core.StandardEngine  : Starting Servlet engine: [Apache Tomcat/9.0.27]
2020-04-27 15:06:28.400  INFO 1872 --- [  restartedMain] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2020-04-27 15:06:28.400  INFO 1872 --- [  restartedMain] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 1446 ms
2020-04-27 15:06:29.144 ERROR 1872 --- [  restartedMain] o.a.c.c.C.[Tomcat].[localhost].[/]       : Exception sending context initialized event to listener instance of class [com.vaadin.flow.spring.VaadinServletContextInitializer$DevModeServletContextListener]

java.lang.IllegalStateException: Parent resource of [/C:/Users/Matěj/Desktop/my-todo/target/classes/com/example/Application.class] not found in the resources!
    at com.vaadin.flow.spring.VaadinServletContextInitializer$CustomResourceLoader.collectResources(VaadinServletContextInitializer.java:680) ~[vaadin-spring-12.1.4.jar:na]
    at com.vaadin.flow.spring.VaadinServletContextInitializer$CustomResourceLoader.getResources(VaadinServletContextInitializer.java:650) ~[vaadin-spring-12.1.4.jar:na]
    at org.springframework.context.annotation.ClassPathScanningCandidateComponentProvider.scanCandidateComponents(ClassPathScanningCandidateComponentProvider.java:421) ~[spring-context-5.2.0.RELEASE.jar:5.2.0.RELEASE]
    at org.springframework.context.annotation.ClassPathScanningCandidateComponentProvider.findCandidateComponents(ClassPathScanningCandidateComponentProvider.java:316) ~[spring-context-5.2.0.RELEASE.jar:5.2.0.RELEASE]
    at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:195) ~[na:na]
    at java.base/java.util.Collections$2.tryAdvance(Collections.java:4747) ~[na:na]
    at java.base/java.util.Collections$2.forEachRemaining(Collections.java:4755) ~[na:na]
    at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484) ~[na:na]
    at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474) ~[na:na]
    at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:913) ~[na:na]
    at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[na:na]
    at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:578) ~[na:na]
    at com.vaadin.flow.spring.VaadinServletContextInitializer$DevModeServletContextListener.contextInitialized(VaadinServletContextInitializer.java:338) ~[vaadin-spring-12.1.4.jar:na]
    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4683) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5146) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) ~[na:na]
    at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:140) ~[na:na]
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:841) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) ~[na:na]
    at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:140) ~[na:na]
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:262) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at org.apache.catalina.core.StandardService.startInternal(StandardService.java:421) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:930) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at org.apache.catalina.startup.Tomcat.start(Tomcat.java:459) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
    at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:107) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.<init>(TomcatWebServer.java:88) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getTomcatWebServer(TomcatServletWebServerFactory.java:438) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getWebServer(TomcatServletWebServerFactory.java:191) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:180) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:153) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:544) ~[spring-context-5.2.0.RELEASE.jar:5.2.0.RELEASE]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at com.example.Application.main(Application.java:14) ~[classes/:na]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[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:566) ~[na:na]
    at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) ~[spring-boot-devtools-2.2.0.RELEASE.jar:2.2.0.RELEASE]

2020-04-27 15:06:29.150 ERROR 1872 --- [  restartedMain] o.apache.catalina.core.StandardContext   : One or more listeners failed to start. Full details will be found in the appropriate container log file
2020-04-27 15:06:29.151 ERROR 1872 --- [  restartedMain] o.apache.catalina.core.StandardContext   : Context [] startup failed due to previous errors
2020-04-27 15:06:29.346  INFO 1872 --- [  restartedMain] o.apache.catalina.core.StandardService   : Stopping service [Tomcat]
2020-04-27 15:06:29.351  WARN 1872 --- [  restartedMain] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat
2020-04-27 15:06:29.360  INFO 1872 --- [  restartedMain] ConditionEvaluationReportLoggingListener : 

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2020-04-27 15:06:29.368 ERROR 1872 --- [  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:156) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:544) ~[spring-context-5.2.0.RELEASE.jar:5.2.0.RELEASE]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at com.example.Application.main(Application.java:14) ~[classes/:na]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[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:566) ~[na:na]
    at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) ~[spring-boot-devtools-2.2.0.RELEASE.jar:2.2.0.RELEASE]
Caused by: org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat
    at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:126) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.<init>(TomcatWebServer.java:88) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getTomcatWebServer(TomcatServletWebServerFactory.java:438) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getWebServer(TomcatServletWebServerFactory.java:191) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:180) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:153) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    ... 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:171) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:110) ~[spring-boot-2.2.0.RELEASE.jar:2.2.0.RELEASE]
    ... 18 common frames omitted

[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  14.399 s
[INFO] Finished at: 2020-04-27T15:06:29+02:00
[INFO] ------------------------------------------------------------------------

I've tried three difdferent versions of JDK (JDK8, JDK11, JDK14), all with the same result.

Current conf:

OS: Windows 10 Pro

Java: Oracle Java SE JDK14

NodeJS: 12

Maven: 3.6.3

It seems my problem is almost identical to the question asked here Why the spring boot vaadin app can not run? , but unfortunately that solution does not work for me.

The minimal Vaadin project can be downloaded at https://vaadin.com/learn/tutorials/vaadin-quick-start in the archive my-todo.zip

Any help would be much appreciated.

Answer 1

For anyone looking for the answer to this, check the discussion under the question. It was an accent letter ( ě ) causing the problem, and it was fixed by having a path to the project that contains only English letters. A bug has been reported to Vaadin on the matter. https://github.com/vaadin/flow/issues/8191