感谢任何帮助来解决以下问题。我正在使用Spring Cloud Hoxton.SR4，并使用spring-cloud-starter-gateway创建了一个网关服务。应用程序在启动时引发以下异常。
org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'discoveryClientRouteDefinitionLocator' defined in class path resource [org/springframework/cloud/gateway/discovery/GatewayDiscoveryClientAutoConfiguration$ReactiveDiscoveryClientRouteDefinitionLocatorConfiguration.class]: Unsatisfied dependency expressed through method 'discoveryClientRouteDefinitionLocator' parameter 1; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'discoveryLocatorProperties' defined in class path resource [org/springframework/cloud/gateway/discovery/GatewayDiscoveryClientAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.cloud.gateway.discovery.DiscoveryLocatorProperties]: Factory method 'discoveryLocatorProperties' threw exception; nested exception is java.lang.NoClassDefFoundError: javax/validation/ValidationException at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:798) ~[spring-beans-5.2.6.RELEASE.jar:5.2.6.RELEASE] at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:539) ~[spring-beans-5.2.6.RELEASE.jar:5.2.6.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1338) ~[spring-beans-5.2.6.RELEASE.jar:5.2.6.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1177) ~[spring-beans-5.2.6.RELEASE.jar:5.2.6.RELEASE] Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.cloud.gateway.discovery.DiscoveryLocatorProperties]: Factory method 'discoveryLocatorProperties' threw exception; nested exception is java.lang.NoClassDefFoundError: javax/validation/ValidationException at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185) ~[spring-beans-5.2.6.RELEASE.jar:5.2.6.RELEASE] at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:651) ~[spring-beans-5.2.6.RELEASE.jar:5.2.6.RELEASE] ... 39 common frames omitted Caused by: java.lang.NoClassDefFoundError: javax/validation/ValidationException at org.springframework.cloud.gateway.discovery.GatewayDiscoveryClientAutoConfiguration.initPredicates(GatewayDiscoveryClientAutoConfiguration.java:61) ~[spring-cloud-gateway-core-2.2.2.RELEASE.jar:2.2.2.RELEASE] at org.springframework.cloud.gateway.discovery.GatewayDiscoveryClientAutoConfiguration.discoveryLocatorProperties(GatewayDiscoveryClientAutoConfiguration.java:86) ~[spring-cloud-gateway-core-2.2.2.RELEASE.jar:2.2.2.RELEASE]enter code here at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_212] at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_212] at sun.reflect.DelegatingMethodAccessorImpl.invoenter code hereke(Unknown Source) ~[na:1.8.0_212] at java.lang.reflect.Method.invoke(Unknown Source) ~[na:1.8.0_212] at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154) ~[spring-beans-5.2.6.RELEASE.jar:5.2.6.RELEASE] ... 40 common frames omitted Caused by: java.lang.ClassNotFoundException: javax.validation.ValidationException at java.net.URLClassLoader.findClass(Unknown Source) ~[na:1.8.0_212] at java.lang.ClassLoader.loadClass(Unknown Source) ~[na:1.8.0_212] at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) ~[na:1.8.0_212] at java.lang.ClassLoader.loadClass(Unknown Source) ~[na:1.8.0_212] ... 47 common frames omitted>
我也将以下条目放在应用程序属性中;但它没有解决问题
spring.cloud.gateway.discovery.locator.enabled=true
spring.cloud.gateway.discovery.locator.lower-case-service-id=true
请参阅： Spring Boot 2.3 发行说明
它说：
从#19550开始，默认情况下，Web和WebFlux启动器不再依赖于验证启动器。如果您的应用程序正在使用验证功能，则需要在构建文件中手动添加对 spring-boot-starter-validation 的依赖项。
Spring Initializr 似乎没有接受这一点，所以现在每个人都缺少验证启动器。
将以下内容添加到 POM 的<dependencies>块中：
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-validation</artifactId>
</dependency>