今天在新建一个springboot项目时，按照以往的流程引入maven；最后在引入swagger并运用@ConditionalOnProperty来控制接口文档显示时报Error starting ApplicationContext. To display the conditions report re-run your application with ‘debug’ enabled.
具体报错如下：
Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled. 2022-03-23 21:06:56.426 ERROR 248 --- [ main] o.s.boot.SpringApplication : Application run failed java.lang.NullPointerException: null at springfox.documentation.spi.service.contexts.Orderings$8.compare(Orderings.java:113) ~[springfox-spi-2.4.0.jar:2.4.0] at springfox.documentation.spi.service.contexts.Orderings$8.compare(Orderings.java:110) ~[springfox-spi-2.4.0.jar:2.4.0] at com.google.common.collect.ComparatorOrdering.compare(ComparatorOrdering.java:37) ~[guava-29.0-jre.jar:na] at java.util.TimSort.countRunAndMakeAscending(TimSort.java:355) ~[na:1.8.0_101] at java.util.TimSort.sort(TimSort.java:220) ~[na:1.8.0_101] at java.util.Arrays.sort(Arrays.java:1438) ~[na:1.8.0_101] at com.google.common.collect.Ordering.sortedCopy(Ordering.java:842) ~[guava-29.0-jre.jar:na] at springfox.documentation.spring.web.plugins.WebMvcRequestHandlerProvider.requestHandlers(WebMvcRequestHandlerProvider.java:51) ~[springfox-spring-web-2.4.0.jar:2.4.0] at springfox.documentation.spring.web.plugins.documentationPluginsBootstrapper$1.apply(documentationPluginsBootstrapper.java:122) ~[springfox-spring-web-2.4.0.jar:2.4.0] at springfox.documentation.spring.web.plugins.documentationPluginsBootstrapper$1.apply(documentationPluginsBootstrapper.java:119) ~[springfox-spring-web-2.4.0.jar:2.4.0] at com.google.common.collect.Iterators$6.transform(Iterators.java:783) ~[guava-29.0-jre.jar:na] at com.google.common.collect.TransformedIterator.next(TransformedIterator.java:47) ~[guava-29.0-jre.jar:na] at com.google.common.collect.TransformedIterator.next(TransformedIterator.java:47) ~[guava-29.0-jre.jar:na] at com.google.common.collect.Iterators$ConcatenatedIterator.hasNext(Iterators.java:1333) ~[guava-29.0-jre.jar:na] at com.google.common.collect.ImmutableList.copyOf(ImmutableList.java:268) ~[guava-29.0-jre.jar:na] at com.google.common.collect.ImmutableList.copyOf(ImmutableList.java:232) ~[guava-29.0-jre.jar:na] at com.google.common.collect.FluentIterable.toList(FluentIterable.java:619) ~[guava-29.0-jre.jar:na] at springfox.documentation.spring.web.plugins.documentationPluginsBootstrapper.defaultContextBuilder(documentationPluginsBootstrapper.java:110) ~[springfox-spring-web-2.4.0.jar:2.4.0] at springfox.documentation.spring.web.plugins.documentationPluginsBootstrapper.buildContext(documentationPluginsBootstrapper.java:101) ~[springfox-spring-web-2.4.0.jar:2.4.0] at springfox.documentation.spring.web.plugins.documentationPluginsBootstrapper.onApplicationEvent(documentationPluginsBootstrapper.java:91) ~[springfox-spring-web-2.4.0.jar:2.4.0] at springfox.documentation.spring.web.plugins.documentationPluginsBootstrapper.onApplicationEvent(documentationPluginsBootstrapper.java:53) ~[springfox-spring-web-2.4.0.jar:2.4.0] at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:176) ~[spring-context-5.3.16.jar:5.3.16] at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:169) ~[spring-context-5.3.16.jar:5.3.16] at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:143) ~[spring-context-5.3.16.jar:5.3.16] at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:421) ~[spring-context-5.3.16.jar:5.3.16] at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:378) ~[spring-context-5.3.16.jar:5.3.16] at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:938) ~[spring-context-5.3.16.jar:5.3.16] at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:586) ~[spring-context-5.3.16.jar:5.3.16] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:145) ~[spring-boot-2.6.4.jar:2.6.4] at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:740) [spring-boot-2.6.4.jar:2.6.4] at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:415) [spring-boot-2.6.4.jar:2.6.4] at org.springframework.boot.SpringApplication.run(SpringApplication.java:303) [spring-boot-2.6.4.jar:2.6.4] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1312) [spring-boot-2.6.4.jar:2.6.4] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1301) [spring-boot-2.6.4.jar:2.6.4] at com.damon.shop.ShopApplication.main(ShopApplication.java:11) [classes/:na]
当springboot用较高版本的2.6.4时 Swagger2Config中必须添加@ConditionalOnProperty(name = “swagger.enable”,havingValue = “true”)
注释注解就启动就会报错
@Configuration
@EnableSwagger2
@ConditionalOnProperty(name = "swagger.enable",havingValue = "true")// 在springboot用较高版本的2.6.4注释启动会报错
public class Swagger2Config {
@Bean
public Docket createRestApi() {
return new Docket(documentationType.SWAGGER_2)
.apiInfo(apiInfo())
.select()
.apis(RequestHandlerSelectors.basePackage("com.damon.shop.controller"))
.paths(PathSelectors.any())
.build();
}
private ApiInfo apiInfo() {
return new ApiInfoBuilder()
.title("Spring Boot 测试使用 Swagger2 构建RESTful API")
.contact(new Contact("DamonYuan", "", ""))
.version("1.0")
.description("API 描述")
.build();
}
}
本人在yml中添加了还是报错；注释了yaml就不会报错，但是问题是就没法运用swagger测试接口
swagger: enable: true解决问题
.... org.springframework.boot spring-boot-starter-parent 2.6.4 io.springfox springfox-swagger-ui 2.4.0 io.springfox springfox-swagger2 2.4.0
== 将springboot中的version降低为2.5.0 或者 2.1.15.RELEASE等版本就可以了。主要原因是swagger与springboot这两个版本可能不兼容导致的==
