swagger-ui.html is not available when running 'java -jar app-name.jar'

[splekhanov]

Description
When running Spring Boot app via IDEA or Maven - swagger-ui.html is available.
When packaging the app in jar and running 'java -jar app-name.jar' - swagger-ui.html is not available.

To Reproduce
Steps to reproduce the behavior:
Spring-boot 2.2.7.RELEASE
Java 1.8.0_231
springdoc-openapi-ui 1.2.32
Test project at my git page https://github.com/splekhanov/springdoc-example

1. Clone springdoc-example
2. Open it in IDEA
3. Run DemoApplication.class
4. Expected: Swagger UI is available at http://localhost:8080/swagger-ui.html
5. Stop the app
6. Perform mvn spring-boot:start
7. Expected: Swagger UI is available at http://localhost:8080/swagger-ui.html
8. Stop the app
9. Perform mvn clean package
10. Launch sb-app-1.0-SNAPSHOT.jar from target folder via cmd: java -jar sb-app-1.0-SNAPSHOT.jar

Expected behavior
Swagger UI is available at http://localhost:8080/swagger-ui.html

Actual behavior
Swagger UI is NOT available at http://localhost:8080/swagger-ui.html
Got 404 NOT FOUND

2020-06-18 13:55:11.014  INFO 2112 --- [nio-8080-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring DispatcherServlet 'dispatcherServlet'
2020-06-18 13:55:11.014  INFO 2112 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : Initializing Servlet 'dispatcherServlet'
2020-06-18 13:55:11.023  INFO 2112 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : Completed initialization in 8 ms
2020-06-18 13:55:11.118 ERROR 2112 --- [nio-8080-exec-1] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] threw exception

javax.servlet.ServletException: Circular view path [error]: would dispatch back to the current handler URL [/error] again. Check your ViewResolver setup! (Hint: This may be the result of an unspecified view, due to default view name generation.)
        at org.springframework.web.servlet.view.InternalResourceView.prepareForRendering(InternalResourceView.java:210) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at org.springframework.web.servlet.view.InternalResourceView.renderMergedOutputModel(InternalResourceView.java:148) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:316) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1373) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1118) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1057) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:634) ~[tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) ~[tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:712) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:461) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:384) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:312) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.StandardHostValve.custom(StandardHostValve.java:394) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.StandardHostValve.status(StandardHostValve.java:253) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:175) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:373) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1590) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) [na:1.8.0_231]
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) [na:1.8.0_231]
        at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at java.lang.Thread.run(Unknown Source) [na:1.8.0_231]

2020-06-18 13:55:11.120 ERROR 2112 --- [nio-8080-exec-1] o.a.c.c.C.[Tomcat].[localhost]           : Exception Processing ErrorPage[errorCode=0, location=/error]

javax.servlet.ServletException: Circular view path [error]: would dispatch back to the current handler URL [/error] again. Check your ViewResolver setup! (Hint: This may be the result of an unspecified view, due to default view name generation.)
        at org.springframework.web.servlet.view.InternalResourceView.prepareForRendering(InternalResourceView.java:210) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at org.springframework.web.servlet.view.InternalResourceView.renderMergedOutputModel(InternalResourceView.java:148) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:316) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1373) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1118) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1057) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:634) ~[tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.2.6.RELEASE.jar!/:5.2.6.RELEASE]
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) ~[tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:712) ~[tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:461) ~[tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:384) ~[tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:312) ~[tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.StandardHostValve.custom(StandardHostValve.java:394) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.StandardHostValve.status(StandardHostValve.java:253) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:175) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:373) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1590) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) [na:1.8.0_231]
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) [na:1.8.0_231]
        at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-9.0.34.jar!/:9.0.34]
        at java.lang.Thread.run(Unknown Source) [na:1.8.0_231]

[bnasslahsen]

Step 4, from your code not working because of this dependency declaration:

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
            <scope>provided</scope>
        </dependency>

Then after removing it, all working like a charm.
Your behaviour is not reproducible.

All the steps you have described are working and there are no known issu about the usage of java-jar ....

You can review your IDE/Project configuration.