Why I having this issue? ![https://i.imgur.com/TEkQhfr.png](https://i.imgur

Why I having this issue? ![https://i.imgur.com/TEkQhfr.png]
(https://i.imgur.com/TEkQhfr.png) . I added to spring

  @Bean
    public ServletRegistrationBean registerComponentAnimations() {
        return new ServletRegistrationBean(new ResourceLoaderServlet(), "/frontend/compani/compani.js");
    }

And reinstall node modules. Nothing helps. Vaadin version 19.0.2.

Usage of the frontend folder has changed a bit in V19. You just need a small change in your spring bean:

@Bean
public ServletRegistrationBean registerComponentAnimations() {
        return new ServletRegistrationBean(new ResourceLoaderServlet(), "/compani/compani.js");
}

Now in dev mode thre is:

ERROR 836 --- [nio-8080-exec-4]
 c.v.flow.server.DefaultErrorHandler      : 

java.io.UncheckedIOException: Failed to extract jar entry 'META-INF/resources/frontend/animate.css' from jarFile 'C:\Users\pavel\IdeaProjects\Pewne_Jutro\target\flow-frontend'
	at com.vaadin.flow.server.frontend.JarContentsManager.copyJarEntryTrimmingBasePath(JarContentsManager.java:324) ~[flow-server-6.0.3.jar:6.0.3]

	at com.vaadin.flow.server.frontend.JarContentsManager.lambda$copyIncludedFilesFromJarTrimmingBasePath$11(JarContentsManager.java:270) ~[flow-server-6.0.3.jar:6.0.3]

	at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183) ~[na:na]

	at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:177) ~[na:na]

	at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:177) ~[na:na]

	at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:177) ~[na:na]

	at java.base/java.util.zip.ZipFile$EntrySpliterator.tryAdvance(ZipFile.java:580) ~[na:na]

	at java.base/java.util.Spliterator.forEachRemaining(Spliterator.java:326) ~[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.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150) ~[na:na]

	at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173) ~[na:na]

	at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[na:na]

	at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:497) ~[na:na]

	at com.vaadin.flow.server.frontend.JarContentsManager.copyIncludedFilesFromJarTrimmingBasePath(JarContentsManager.java:270) ~[flow-server-6.0.3.jar:6.0.3]

	at com.vaadin.flow.server.frontend.TaskCopyFrontendFiles.execute(TaskCopyFrontendFiles.java:80) ~[flow-server-6.0.3.jar:6.0.3]

	at com.vaadin.flow.server.frontend.NodeTasks.execute(NodeTasks.java:698) ~[flow-server-6.0.3.jar:6.0.3]

	at com.vaadin.flow.server.startup.DevModeInitializer.runNodeTasks(DevModeInitializer.java:487) ~[flow-server-6.0.3.jar:6.0.3]

	at com.vaadin.flow.server.startup.DevModeInitializer.lambda$initDevModeHandler$0(DevModeInitializer.java:377) ~[flow-server-6.0.3.jar:6.0.3]

	at java.base/java.util.concurrent.CompletableFuture$AsyncRun.run(CompletableFuture.java:1736) ~[na:na]

	at java.base/java.util.concurrent.CompletableFuture$AsyncRun.exec(CompletableFuture.java:1728) ~[na:na]

	at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:290) ~[na:na]

	at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1020) ~[na:na]

	at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1656) ~[na:na]

	at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1594) ~[na:na]

	at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:183) ~[na:na]

Caused by: java.io.IOException: Can't compare directories, only files
	at org.apache.commons.io.FileUtils.contentEquals(FileUtils.java:740) ~[commons-io-2.6.jar:2.6]

	at com.vaadin.flow.server.frontend.JarContentsManager.copyJarEntryTrimmingBasePath(JarContentsManager.java:313) ~[flow-server-6.0.3.jar:6.0.3]

	... 25 common frames omitted

2021-03-31 20:56:25.189 ERROR 836 --- [nio-8080-exec-4]
 o.a.c.c.C.[.[.
[/]
.[springServlet]
        : Servlet.service() for servlet [springServlet]
 threw exception

java.io.IOException: Can't compare directories, only files
	at org.apache.commons.io.FileUtils.contentEquals(FileUtils.java:740) ~[commons-io-2.6.jar:2.6]

	at com.vaadin.flow.server.frontend.JarContentsManager.copyJarEntryTrimmingBasePath(JarContentsManager.java:313) ~[flow-server-6.0.3.jar:6.0.3]

	at com.vaadin.flow.server.frontend.JarContentsManager.lambda$copyIncludedFilesFromJarTrimmingBasePath$11(JarContentsManager.java:270) ~[flow-server-6.0.3.jar:6.0.3]

	at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183) ~[na:na]

	at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:177) ~[na:na]

	at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:177) ~[na:na]

	at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:177) ~[na:na]

	at java.base/java.util.zip.ZipFile$EntrySpliterator.tryAdvance(ZipFile.java:580) ~[na:na]

	at java.base/java.util.Spliterator.forEachRemaining(Spliterator.java:326) ~[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.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150) ~[na:na]

	at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173) ~[na:na]

	at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[na:na]

	at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:497) ~[na:na]

	at com.vaadin.flow.server.frontend.JarContentsManager.copyIncludedFilesFromJarTrimmingBasePath(JarContentsManager.java:270) ~[flow-server-6.0.3.jar:6.0.3]

	at com.vaadin.flow.server.frontend.TaskCopyFrontendFiles.execute(TaskCopyFrontendFiles.java:80) ~[flow-server-6.0.3.jar:6.0.3]

	at com.vaadin.flow.server.frontend.NodeTasks.execute(NodeTasks.java:698) ~[flow-server-6.0.3.jar:6.0.3]

	at com.vaadin.flow.server.startup.DevModeInitializer.runNodeTasks(DevModeInitializer.java:487) ~[flow-server-6.0.3.jar:6.0.3]

	at com.vaadin.flow.server.startup.DevModeInitializer.lambda$initDevModeHandler$0(DevModeInitializer.java:377) ~[flow-server-6.0.3.jar:6.0.3]

	at java.base/java.util.concurrent.CompletableFuture$AsyncRun.run(CompletableFuture.java:1736) ~[na:na]

	at java.base/java.util.concurrent.CompletableFuture$AsyncRun.exec(CompletableFuture.java:1728) ~[na:na]

	at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:290) ~[na:na]

	at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1020) ~[na:na]

	at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1656) ~[na:na]

	at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1594) ~[na:na]

	at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:183) ~[na:na]


command mvn vaadin: build-frontend :

Failed to execute goal com.vaadin:vaadin-maven-plugin:19.0.2:build-frontend (default-cli) on project my-insurance-manager: Execution default-cli of goal com.vaadin:vaadin-maven-plugin:19.0.2:build-frontend failed: Failed to extract jar entry 'META-INF/resources/frontend/animate.css' from jarFile 'C:\Users\pavel\IdeaProjects\Pewne_Jutro\target\flow-frontend'

Spring isn’t starting. Nothing happend after Copying frontend resources from jar files …

[https://i.imgur.com/tCw9ZWY.png]
(https://i.imgur.com/tCw9ZWY.png)

Ok I know what happens. I was using before another animation addon and there is an conflict. After remove that addon from pom.xml your solution is working. Thank you very much.

@Bean
public ServletRegistrationBean registerComponentAnimations() {
        return new ServletRegistrationBean(new ResourceLoaderServlet(), "/compani/compani.js");
}