Spring WebClientHateoasConfiguration has runtime dependency upon spring-test

The WebClientHateoasConfiguration has a runtime dependency upon spring-test. I'm not sure if this is working as designed, but It is unusual for Spring applications to have to include spring-test as a runtime dependency. Usually spring-test is included as a test scope dependency only, which makes it unavailable at runtime.

Steps to reproduce: 1. Create a Spring Boot 2.3.0.M4 project with webflux and hateoas dependencies 2. Run with mvn spring-boot:run 3. Observe the following exception in the log:

java.lang.IllegalStateException: Failed to introspect Class [org.springframework.hateoas.config.WebClientHateoasConfiguration] from ClassLoader [jdk.internal.loader.ClassLoaders$AppClassLoader@277050dc]
    at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:481) ~[spring-core-5.2.5.RELEASE.jar:5.2.5.RELEASE]
    at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:358) ~[spring-core-5.2.5.RELEASE.jar:5.2.5.RELEASE]
    at org.springframework.util.ReflectionUtils.getUniqueDeclaredMethods(ReflectionUtils.java:414) ~[spring-core-5.2.5.RELEASE.jar:5.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.lambda$getTypeForFactoryMethod$2(AbstractAutowireCapableBeanFactory.java:743) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
    at java.base/java.util.concurrent.ConcurrentHashMap.computeIfAbsent(ConcurrentHashMap.java:1737) ~[na:na]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.getTypeForFactoryMethod(AbstractAutowireCapableBeanFactory.java:742) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.determineTargetType(AbstractAutowireCapableBeanFactory.java:681) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.predictBeanType(AbstractAutowireCapableBeanFactory.java:649) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:1605) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doGetBeanNamesForType(DefaultListableBeanFactory.java:523) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanNamesForType(DefaultListableBeanFactory.java:494) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeansOfType(DefaultListableBeanFactory.java:616) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeansOfType(DefaultListableBeanFactory.java:608) ~[spring-beans-5.2.5.RELEASE.jar:5.2.5.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.getBeansOfType(AbstractApplicationContext.java:1242) ~[spring-context-5.2.5.RELEASE.jar:5.2.5.RELEASE]
    at org.springframework.boot.SpringApplication.getExitCodeFromMappedException(SpringApplication.java:880) ~[spring-boot-2.3.0.M4.jar:2.3.0.M4]
    at org.springframework.boot.SpringApplication.getExitCodeFromException(SpringApplication.java:868) ~[spring-boot-2.3.0.M4.jar:2.3.0.M4]
    at org.springframework.boot.SpringApplication.handleExitCode(SpringApplication.java:855) ~[spring-boot-2.3.0.M4.jar:2.3.0.M4]
    at org.springframework.boot.SpringApplication.handleRunFailure(SpringApplication.java:806) ~[spring-boot-2.3.0.M4.jar:2.3.0.M4]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:325) ~[spring-boot-2.3.0.M4.jar:2.3.0.M4]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1237) ~[spring-boot-2.3.0.M4.jar:2.3.0.M4]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) ~[spring-boot-2.3.0.M4.jar:2.3.0.M4]
    at com.example.demo.DemoApplication.main(DemoApplication.java:10) ~[classes/:na]
Caused by: java.lang.NoClassDefFoundError: org/springframework/test/web/reactive/server/WebTestClientConfigurer
    at java.base/java.lang.ClassLoader.defineClass1(Native Method) ~[na:na]
    at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1016) ~[na:na]
    at java.base/java.security.SecureClassLoader.defineClass(SecureClassLoader.java:174) ~[na:na]
    at java.base/jdk.internal.loader.BuiltinClassLoader.defineClass(BuiltinClassLoader.java:800) ~[na:na]
    at java.base/jdk.internal.loader.BuiltinClassLoader.findClassOnClassPathOrNull(BuiltinClassLoader.java:698) ~[na:na]
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(BuiltinClassLoader.java:621) ~[na:na]
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:579) ~[na:na]
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) ~[na:na]
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) ~[na:na]
    at java.base/java.lang.Class.getDeclaredMethods0(Native Method) ~[na:na]
    at java.base/java.lang.Class.privateGetDeclaredMethods(Class.java:3166) ~[na:na]
    at java.base/java.lang.Class.getDeclaredMethods(Class.java:2309) ~[na:na]
    at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:463) ~[spring-core-5.2.5.RELEASE.jar:5.2.5.RELEASE]
    ... 21 common frames omitted
Caused by: java.lang.ClassNotFoundException: org.springframework.test.web.reactive.server.WebTestClientConfigurer
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:581) ~[na:na]
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) ~[na:na]
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) ~[na:na]
    ... 34 common frames omitted

Comment From: bclozel

This issue belongs to the Spring HATEOAS project. It’s been reported and fixed here already: https://github.com/spring-projects/spring-hateoas/issues/1252 Thanks!