The integration of swagger version 3.0.0 and springboot (version 2.6.1) failed to start
2021-12-22 22:56:56.981 INFO 18628 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 8080 (http)
2021-12-22 22:56:56.993 INFO 18628 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat]
2021-12-22 22:56:56.994 INFO 18628 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet engine: [Apache Tomcat/9.0.55]
2021-12-22 22:56:57.063 INFO 18628 --- [ main] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2021-12-22 22:56:57.063 INFO 18628 --- [ main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 919 ms
2021-12-22 22:56:57.434 INFO 18628 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8080 (http) with context path ''
2021-12-22 22:56:57.437 WARN 18628 --- [ main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.context.ApplicationContextException: Failed to start bean 'documentationPluginsBootstrapper'; nested exception is java.lang.NullPointerException
2021-12-22 22:56:57.773 INFO 18628 --- [ main] o.apache.catalina.core.StandardService : Stopping service [Tomcat]
2021-12-22 22:56:57.784 INFO 18628 --- [ main] ConditionEvaluationReportLoggingListener :
Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2021-12-22 22:56:57.810 ERROR 18628 --- [ main] o.s.boot.SpringApplication : Application run failed
org.springframework.context.ApplicationContextException: Failed to start bean 'documentationPluginsBootstrapper'; nested exception is java.lang.NullPointerException
at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:181) ~[spring-context-5.3.13.jar:5.3.13]
at org.springframework.context.support.DefaultLifecycleProcessor.access$200(DefaultLifecycleProcessor.java:54) ~[spring-context-5.3.13.jar:5.3.13]
at org.springframework.context.support.DefaultLifecycleProcessor$LifecycleGroup.start(DefaultLifecycleProcessor.java:356) ~[spring-context-5.3.13.jar:5.3.13]
at java.lang.Iterable.forEach(Iterable.java:75) ~[na:1.8.0_144]
at org.springframework.context.support.DefaultLifecycleProcessor.startBeans(DefaultLifecycleProcessor.java:155) ~[spring-context-5.3.13.jar:5.3.13]
at org.springframework.context.support.DefaultLifecycleProcessor.onRefresh(DefaultLifecycleProcessor.java:123) ~[spring-context-5.3.13.jar:5.3.13]
at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:935) ~[spring-context-5.3.13.jar:5.3.13]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:586) ~[spring-context-5.3.13.jar:5.3.13]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:145) ~[spring-boot-2.6.1.jar:2.6.1]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:730) [spring-boot-2.6.1.jar:2.6.1]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:412) [spring-boot-2.6.1.jar:2.6.1]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:302) [spring-boot-2.6.1.jar:2.6.1]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1301) [spring-boot-2.6.1.jar:2.6.1]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1290) [spring-boot-2.6.1.jar:2.6.1]
at com.hkx.swagger.SwaggerDemoApplication.main(SwaggerDemoApplication.java:12) [classes/:na]
Caused by: java.lang.NullPointerException: null
at springfox.documentation.spring.web.WebMvcPatternsRequestConditionWrapper.getPatterns(WebMvcPatternsRequestConditionWrapper.java:56) ~[springfox-spring-webmvc-3.0.0.jar:3.0.0]
at springfox.documentation.RequestHandler.sortedPaths(RequestHandler.java:113) ~[springfox-core-3.0.0.jar:3.0.0]
at springfox.documentation.spi.service.contexts.Orderings.lambda$byPatternsCondition$3(Orderings.java:89) ~[springfox-spi-3.0.0.jar:3.0.0]
at java.util.Comparator.lambda$comparing$77a9974f$1(Comparator.java:469) ~[na:1.8.0_144]
at java.util.TimSort.countRunAndMakeAscending(TimSort.java:355) ~[na:1.8.0_144]
at java.util.TimSort.sort(TimSort.java:220) ~[na:1.8.0_144]
at java.util.Arrays.sort(Arrays.java:1512) ~[na:1.8.0_144]
at java.util.ArrayList.sort(ArrayList.java:1454) ~[na:1.8.0_144]
at java.util.stream.SortedOps$RefSortingSink.end(SortedOps.java:387) ~[na:1.8.0_144]
at java.util.stream.Sink$ChainedReference.end(Sink.java:258) ~[na:1.8.0_144]
at java.util.stream.Sink$ChainedReference.end(Sink.java:258) ~[na:1.8.0_144]
at java.util.stream.Sink$ChainedReference.end(Sink.java:258) ~[na:1.8.0_144]
at java.util.stream.Sink$ChainedReference.end(Sink.java:258) ~[na:1.8.0_144]
at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:482) ~[na:1.8.0_144]
at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471) ~[na:1.8.0_144]
at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708) ~[na:1.8.0_144]
at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[na:1.8.0_144]
at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499) ~[na:1.8.0_144]
at springfox.documentation.spring.web.plugins.WebMvcRequestHandlerProvider.requestHandlers(WebMvcRequestHandlerProvider.java:81) ~[springfox-spring-webmvc-3.0.0.jar:3.0.0]
at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193) ~[na:1.8.0_144]
at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1374) ~[na:1.8.0_144]
at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481) ~[na:1.8.0_144]
at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471) ~[na:1.8.0_144]
at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708) ~[na:1.8.0_144]
at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[na:1.8.0_144]
at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499) ~[na:1.8.0_144]
at springfox.documentation.spring.web.plugins.AbstractDocumentationPluginsBootstrapper.withDefaults(AbstractDocumentationPluginsBootstrapper.java:107) ~[springfox-spring-web-3.0.0.jar:3.0.0]
at springfox.documentation.spring.web.plugins.AbstractDocumentationPluginsBootstrapper.buildContext(AbstractDocumentationPluginsBootstrapper.java:91) ~[springfox-spring-web-3.0.0.jar:3.0.0]
at springfox.documentation.spring.web.plugins.AbstractDocumentationPluginsBootstrapper.bootstrapDocumentationPlugins(AbstractDocumentationPluginsBootstrapper.java:82) ~[springfox-spring-web-3.0.0.jar:3.0.0]
at springfox.documentation.spring.web.plugins.DocumentationPluginsBootstrapper.start(DocumentationPluginsBootstrapper.java:100) ~[springfox-spring-web-3.0.0.jar:3.0.0]
at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:178) ~[spring-context-5.3.13.jar:5.3.13]
... 14 common frames omitted
进程完成，退出码 1
The error report is the general content of the above, and then his general idea is the problem of backpacking, and then there are many solutions that have been tried
The first is the version of swagger. It is said that the version below 3.0.0 is used, but the result is that it does not work.
<!-- https://mvnrepository.com/artifact/io.springfox/springfox-swagger2 -->
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger2</artifactId>
<version>2.9.2</version>
</dependency>
<!-- https://mvnrepository.com/artifact/io.springfox/springfox-swagger-ui -->
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger-ui</artifactId>
<version>2.9.2</version>
</dependency>
No, it still can’t start, and the same error is reported
The second is to use the 3.0.0 version and replace it with 3 packages, and add the package that started
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger-ui</artifactId>
<version>3.0.0</version>
</dependency>
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger2</artifactId>
<version>3.0.0</version>
</dependency>
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-boot-starter</artifactId>
<version>3.0.0</version>
</dependency>
The result is still the same
. Wait, I won’t list them one by one.
Finally, I found a blog that reminded me
of the springboot version problem, and then I changed the version. Record the
integration of springboot2.6.0 and swagger 3.0.0 The problem of startup failure
is temporarily solved by changing to a usable version:
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.5.6</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
Thanks to the blog Springboot for integrating the springfox used by swagger to report an error