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-5.3.22.jar:5.3.22]
	at org.springframework.context.support.DefaultLifecycleProcessor.access$200(DefaultLifecycleProcessor.java:54) ~[spring-context-5.3.22.jar:5.3.22]
	at org.springframework.context.support.DefaultLifecycleProcessor$LifecycleGroup.start(DefaultLifecycleProcessor.java:356) ~[spring-context-5.3.22.jar:5.3.22]
	at java.lang.Iterable.forEach(Iterable.java:75) ~[na:1.8.0_131]
	at org.springframework.context.support.DefaultLifecycleProcessor.startBeans(DefaultLifecycleProcessor.java:155) ~[spring-context-5.3.22.jar:5.3.22]
	at org.springframework.context.support.DefaultLifecycleProcessor.onRefresh(DefaultLifecycleProcessor.java:123) ~[spring-context-5.3.22.jar:5.3.22]
	at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:935) ~[spring-context-5.3.22.jar:5.3.22]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:586) ~[spring-context-5.3.22.jar:5.3.22]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:147) ~[spring-boot-2.7.3.jar:2.7.3]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:734) [spring-boot-2.7.3.jar:2.7.3]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:408) [spring-boot-2.7.3.jar:2.7.3]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:308) [spring-boot-2.7.3.jar:2.7.3]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1306) [spring-boot-2.7.3.jar:2.7.3]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1295) [spring-boot-2.7.3.jar:2.7.3]
	at com.yuhuofei.SpringbootSwaggerApplication.main(SpringbootSwaggerApplication.java:10) [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$1(Comparator.java:469) ~[na:1.8.0_131]
	at java.util.TimSort.countRunAndMakeAscending(TimSort.java:355) ~[na:1.8.0_131]
	at java.util.TimSort.sort(TimSort.java:220) ~[na:1.8.0_131]
	at java.util.Arrays.sort(Arrays.java:1512) ~[na:1.8.0_131]
	at java.util.ArrayList.sort(ArrayList.java:1454) ~[na:1.8.0_131]
	at java.util.stream.SortedOps$RefSortingSink.end(SortedOps.java:387) ~[na:1.8.0_131]
	at java.util.stream.Sink$ChainedReference.end(Sink.java:258) ~[na:1.8.0_131]
	at java.util.stream.Sink$ChainedReference.end(Sink.java:258) ~[na:1.8.0_131]
	at java.util.stream.Sink$ChainedReference.end(Sink.java:258) ~[na:1.8.0_131]
	at java.util.stream.Sink$ChainedReference.end(Sink.java:258) ~[na:1.8.0_131]
	at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:482) ~[na:1.8.0_131]
	at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471) ~[na:1.8.0_131]
	at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708) ~[na:1.8.0_131]
	at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[na:1.8.0_131]
	at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499) ~[na:1.8.0_131]
	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$1.accept(ReferencePipeline.java:193) ~[na:1.8.0_131]
	at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1374) ~[na:1.8.0_131]
	at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481) ~[na:1.8.0_131]
	at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471) ~[na:1.8.0_131]
	at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708) ~[na:1.8.0_131]
	at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[na:1.8.0_131]
	at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499) ~[na:1.8.0_131]
	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-5.3.22.jar:5.3.22]
	... 14 common frames omitted

Use version information

• SpringBoot 2.7.3
• springfox-boot-starter 3.0.0

Use the above version of the dependency package for integration, start the service, and directly report the previous error. It is preliminarily determined that the problem should be caused by the version.

Cause:

After springboot 2.6.0, the default path matching policy of spring MVC was changed from AntPathMatcher to PathPatternParser, resulting in an error in starting the service.

Solution:

Add the following line of configuration information to the application.properties configuration file to solve the problem

#How to Solve swagger error
spring.mvc.pathmatch.matching-strategy=ant_path_matcher