【2-7 创建Web方法测试Swagger】集成Swagger启动报错

Question

老师，我把您的代码原样拷贝到我的环境下启动，也一样报这个错误。

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
22:05:03  ERROR  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)
	at org.springframework.context.support.DefaultLifecycleProcessor.access$200(DefaultLifecycleProcessor.java:54)
	at org.springframework.context.support.DefaultLifecycleProcessor$LifecycleGroup.start(DefaultLifecycleProcessor.java:356)
	at java.base/java.lang.Iterable.forEach(Iterable.java:75)
	at org.springframework.context.support.DefaultLifecycleProcessor.startBeans(DefaultLifecycleProcessor.java:155)
	at org.springframework.context.support.DefaultLifecycleProcessor.onRefresh(DefaultLifecycleProcessor.java:123)
	at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:935)
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:586)
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:145)
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:730)
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:412)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:302)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1301)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1290)
	at com.zerone.emos.wx.EmosWxApiApplication.main(EmosWxApiApplication.java:10)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:567)
	at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49)
Caused by: java.lang.NullPointerException: null
	at springfox.documentation.spi.service.contexts.Orderings$8.compare(Orderings.java:112)
	at springfox.documentation.spi.service.contexts.Orderings$8.compare(Orderings.java:109)
	at com.google.common.collect.ComparatorOrdering.compare(ComparatorOrdering.java:37)
	at java.base/java.util.TimSort.countRunAndMakeAscending(TimSort.java:355)
	at java.base/java.util.TimSort.sort(TimSort.java:220)
	at java.base/java.util.Arrays.sort(Arrays.java:1442)
	at com.google.common.collect.Ordering.sortedCopy(Ordering.java:855)
	at springfox.documentation.spring.web.plugins.WebMvcRequestHandlerProvider.requestHandlers(WebMvcRequestHandlerProvider.java:57)
	at springfox.documentation.spring.web.plugins.DocumentationPluginsBootstrapper$2.apply(DocumentationPluginsBootstrapper.java:138)
	at springfox.documentation.spring.web.plugins.DocumentationPluginsBootstrapper$2.apply(DocumentationPluginsBootstrapper.java:135)
	at com.google.common.collect.Iterators$7.transform(Iterators.java:750)
	at com.google.common.collect.TransformedIterator.next(TransformedIterator.java:47)
	at com.google.common.collect.TransformedIterator.next(TransformedIterator.java:47)
	at com.google.common.collect.MultitransformedIterator.hasNext(MultitransformedIterator.java:52)
	at com.google.common.collect.MultitransformedIterator.hasNext(MultitransformedIterator.java:50)
	at com.google.common.collect.ImmutableList.copyOf(ImmutableList.java:249)
	at com.google.common.collect.ImmutableList.copyOf(ImmutableList.java:209)
	at com.google.common.collect.FluentIterable.toList(FluentIterable.java:614)
	at springfox.documentation.spring.web.plugins.DocumentationPluginsBootstrapper.defaultContextBuilder(DocumentationPluginsBootstrapper.java:111)
	at springfox.documentation.spring.web.plugins.DocumentationPluginsBootstrapper.buildContext(DocumentationPluginsBootstrapper.java:96)
	at springfox.documentation.spring.web.plugins.DocumentationPluginsBootstrapper.start(DocumentationPluginsBootstrapper.java:167)
	at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:178)
	... 19 common frames omitted```

Answer 1

提问者 布辛 2021-12-21 22:20:56

老师，对比了和您的代码，我知道问题出在哪里了，是因为我的springboot版本太高了，因为是idea自动生成的，springboot是2.6的，我修改回和您一样的版本就可以了。

• WPaulG #1

  我也试了，老师用的SpringBoot版本是 2.3.4.RELEASE，改了就好了。

• 幕布斯5172899 #2

  我也改了，我没找到2.3.4.RELEASE，我找了个2.2.2.RELEASE