Spring Boot 2.7.5升级后STS中出现依赖注入异常求助

将Spring Boot版本从2.3.0升级到2.7.5后，在STS中启动应用时遇到依赖注入相关异常，核心错误为java.lang.NoClassDefFoundError: kotlin/reflect/full/KClasses，导致userTypeRepository无法创建，进而影响userService的初始化。

相关代码 #

UserService #

package com.appmakers.xyz.service

import org.passay.CharacterRule
import org.passay.EnglishCharacterData
import org.passay.PasswordGenerator
import org.springframework.beans.factory.annotation.Autowired
import org.springframework.mail.javamail.JavaMailSender
import org.springframework.mail.javamail.MimeMessageHelper
import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder
import org.springframework.stereotype.Service
import java.net.UnknownHostException
import java.text.SimpleDateFormat
import java.util.*
import javax.mail.MessagingException

@Service
class UserService {

    @Autowired
    private lateinit var bCryptPasswordEncoder: BCryptPasswordEncoder

    @Autowired
    private lateinit var userTypeRepository: com.appmakers.vinox.repository.UserTypeRepository

    @Autowired
    private lateinit var userRepository: com.appmakers.vinox.repository.UserRepository

    @Autowired
    private lateinit var javaMailSender: JavaMailSender
}

UserRepository #

package com.appmakers.xyz.repository

import com.appmakers.xyz.entity.User
import com.appmakers.xyz.entity.UserType
import org.springframework.data.jpa.repository.JpaRepository
import org.springframework.stereotype.Repository

@Repository
interface UserRepository : JpaRepository<User?, Long?> {

    fun findUserByEmail(email: String?): User?
    fun findUserById(id: Long?): User
    fun findAllByUserTypeIs(userType: UserType?): List<User>

}

Application #

package com.appmakers.xyz

import com.vaadin.flow.component.dependency.NpmPackage
import com.vaadin.flow.component.page.AppShellConfigurator
import com.vaadin.flow.server.PWA
import com.vaadin.flow.theme.Theme
import org.springframework.boot.SpringApplication
import org.springframework.boot.autoconfigure.SpringBootApplication
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer
import org.springframework.data.jpa.repository.config.EnableJpaRepositories

@SpringBootApplication
@Theme(value = "xyz")
@PWA(name = "V-inox", shortName = "V-inox", offlineResources = [])
@NpmPackage(value = "line-awesome", version = "1.3.0")
@NpmPackage(value = "@vaadin-component-factory/vcf-nav", version = "1.0.6")
@EnableJpaRepositories
open class Application : SpringBootServletInitializer(), AppShellConfigurator {

    companion object {
        @JvmStatic
        fun main(args: Array<String>) {
            SpringApplication.run(Application::class.java, *args)
        }
    }

}

错误堆栈 #

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userService': Unsatisfied dependency expressed through field 'userTypeRepository'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userTypeRepository' defined in com.appmakers.vinox.repository.UserTypeRepository defined in @EnableJpaRepositories declared on Application: Invocation of init method failed; nested exception is java.lang.NoClassDefFoundError: kotlin/reflect/full/KClasses
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.resolveFieldValue(AutowiredAnnotationBeanPostProcessor.java:659) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:639) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:119) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:399) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1431) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:619) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:955) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:918) ~[spring-context-5.3.23.jar:5.3.23]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:583) ~[spring-context-5.3.23.jar:5.3.23]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:147) ~[spring-boot-2.7.5.jar:2.7.5]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:734) ~[spring-boot-2.7.5.jar:2.7.5]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:408) ~[spring-boot-2.7.5.jar:2.7.5]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:308) ~[spring-boot-2.7.5.jar:2.7.5]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1306) ~[spring-boot-2.7.5.jar:2.7.5]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1295) ~[spring-boot-2.7.5.jar:2.7.5]
    at com.appmakers.vinox.Application$Companion.main(Application.kt:33) ~[classes/:na]
    at com.appmakers.vinox.Application.main(Application.kt) ~[classes/:na]
    at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104) ~[na:na]
    at java.base/java.lang.reflect.Method.invoke(Method.java:578) ~[na:na]
    at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) ~[spring-boot-devtools-2.7.5.jar:2.7.5]
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userTypeRepository' defined in com.appmakers.vinox.repository.UserTypeRepository defined in @EnableJpaRepositories declared on Application: Invocation of init method failed; nested exception is java.lang.NoClassDefFoundError: kotlin/reflect/full/KClasses
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1804) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:620) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1391) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1311) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.resolveFieldValue(AutowiredAnnotationBeanPostProcessor.java:656) ~[spring-beans-5.3.23.jar:5.3.23]
    ... 24 common frames omitted
Caused by: java.lang.NoClassDefFoundError: kotlin/reflect/full/KClasses
    at org.springframework.data.mapping.model.PreferredConstructorDiscoverer$Discoverers$2.lambda$discover$3(PreferredConstructorDiscoverer.java:165) ~[spring-data-commons-2.7.5.jar:2.7.5]
    at java.base/java.util.Optional.orElseGet(Optional.java:364) ~[na:na]
    at org.springframework.data.mapping.model.PreferredConstructorDiscoverer$Discoverers$2.discover(PreferredConstructorDiscoverer.java:162) ~[spring-data-commons-2.7.5.jar:2.7.5]
    at org.springframework.data.mapping.model.PreferredConstructorDiscoverer.discover(PreferredConstructorDiscoverer.java:81) ~[spring-data-commons-2.7.5.jar:2.7.5]
    at org.springframework.data.mapping.model.InstanceCreatorMetadataDiscoverer.discover(InstanceCreatorMetadataDiscoverer.java:83) ~[spring-data-commons-2.7.5.jar:2.7.5]
    at org.springframework.data.mapping.model.BasicPersistentEntity.<init>(BasicPersistentEntity.java:113) ~[spring-data-commons-2.7.5.jar:2.7.5]
    at org.springframework.data.jpa.mapping.JpaPersistentEntityImpl.<init>(JpaPersistentEntityImpl.java:59) ~[spring-data-jpa-2.7.5.jar:2.7.5]
    at org.springframework.data.jpa.mapping.JpaMetamodelMappingContext.createPersistentEntity(JpaMetamodelMappingContext.java:71) ~[spring-data-jpa-2.7.5.jar:2.7.5]
    at org.springframework.data.jpa.mapping.JpaMetamodelMappingContext.createPersistentEntity(JpaMetamodelMappingContext.java:44) ~[spring-data-jpa-2.7.5.jar:2.7.5]
    at org.springframework.data.mapping.context.AbstractMappingContext.doAddPersistentEntity(AbstractMappingContext.java:430) ~[spring-data-commons-2.7.5.jar:2.7.5]
    at org.springframework.data.mapping.context.AbstractMappingContext.addPersistentEntity(AbstractMappingContext.java:406) ~[spring-data-commons-2.7.5.jar:2.7.5]
    at org.springframework.data.mapping.context.AbstractMappingContext.getPersistentEntity(AbstractMappingContext.java:291) ~[spring-data-commons-2.7.5.jar:2.7.5]
    at org.springframework.data.mapping.context.AbstractMappingContext.getPersistentEntity(AbstractMappingContext.java:209) ~[spring-data-commons-2.7.5.jar:2.7.5]
    at org.springframework.data.mapping.context.AbstractMappingContext.getPersistentEntity(AbstractMappingContext.java:92) ~[spring-data-commons-2.7.5.jar:2.7.5]
    at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.lambda$afterPropertiesSet$6(RepositoryFactoryBeanSupport.java:326) ~[spring-data-commons-2.7.5.jar:2.7.5]
    at java.base/java.util.Optional.ifPresent(Optional.java:178) ~[na:na]
    at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.afterPropertiesSet(RepositoryFactoryBeanSupport.java:326) ~[spring-data-commons-2.7.5.jar:2.7.5]
    at org.springframework.data.jpa.repository.support.JpaRepositoryFactoryBean.afterPropertiesSet(JpaRepositoryFactoryBean.java:144) ~[spring-data-jpa-2.7.5.jar:2.7.5]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1863) ~[spring-beans-5.3.23.jar:5.3.23]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1800) ~[spring-beans-5.3.23.jar:5.3.23]
    ... 34 common frames omitted
Caused by: java.lang.ClassNotFoundException: kotlin.reflect.full.KClasses
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641) ~[na:na]
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188) ~[na:na]
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) ~[na:na]
    ... 54 common frames omitted

解决方案 #

这个异常的根本原因是Spring Data 2.7.x版本增强了对Kotlin反射的依赖，用于发现实体类的构造函数，但项目中缺少kotlin-reflect依赖。只需在项目的依赖管理中添加该依赖即可解决问题：

Gradle（Kotlin DSL） #

implementation("org.jetbrains.kotlin:kotlin-reflect")

Gradle（Groovy） #

implementation 'org.jetbrains.kotlin:kotlin-reflect'

Maven #

<dependency>
    <groupId>org.jetbrains.kotlin</groupId>
    <artifactId>kotlin-reflect</artifactId>
</dependency>

添加依赖后，重新构建并启动应用，Spring就能正常加载Kotlin反射类，完成Repository的初始化和依赖注入。

内容的提问来源于stack exchange，提问作者Dominik