Kotlin 1.3 + Spring Boot：已经有 '...' bean 方法

Question

我正在尝试将 Spring Boot 项目从 Kotlin 1.2.71 迁移到 1.3.0。 当我更新 Kotlin 版本时，应用程序上下文无法加载并显示以下堆栈跟踪：

[...]
Caused by: java.lang.IllegalStateException: Ambiguous mapping. Cannot map 'universityController' method 
public final com.vindedu.api.view.university.UniversityApplicationOverview com.vindedu.api.controller.UniversityController.getApplications(org.springframework.security.core.userdetails.UserDetails,boolean)
to {[/uni/applications],methods=[GET]}: There is already 'universityController' bean method
public static com.vindedu.api.view.university.UniversityApplicationOverview com.vindedu.api.controller.UniversityController.getApplications$default(com.vindedu.api.controller.UniversityController,org.springframework.security.core.userdetails.UserDetails,boolean,int,java.lang.Object) mapped.
    at org.springframework.web.servlet.handler.AbstractHandlerMethodMapping$MappingRegistry.assertUniqueMethodMapping(AbstractHandlerMethodMapping.java:576)
    at org.springframework.web.servlet.handler.AbstractHandlerMethodMapping$MappingRegistry.register(AbstractHandlerMethodMapping.java:540)
    at org.springframework.web.servlet.handler.AbstractHandlerMethodMapping.registerHandlerMethod(AbstractHandlerMethodMapping.java:264)
    at org.springframework.web.servlet.handler.AbstractHandlerMethodMapping.detectHandlerMethods(AbstractHandlerMethodMapping.java:250)
    at org.springframework.web.servlet.handler.AbstractHandlerMethodMapping.initHandlerMethods(AbstractHandlerMethodMapping.java:214)
    at org.springframework.web.servlet.handler.AbstractHandlerMethodMapping.afterPropertiesSet(AbstractHandlerMethodMapping.java:184)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping.afterPropertiesSet(RequestMappingHandlerMapping.java:127)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1687)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1624)
    ... 98 more

我的UniversityController 类中的以下函数映射到/uni/applications/...：

    @ApiOperation("Get applications received from students", tags = ["University API"],
            authorizations = [Authorization(value = "basicAuth")])
    @RequestMapping(method = [RequestMethod.GET], path = ["/uni/applications"])
    fun getApplications(@AuthenticationPrincipal user: UserDetails, @RequestParam("visible") visible: Boolean = true): UniversityApplicationOverview {
        return universityMessagingService.getApplications(user, visible)
    }

    @ApiOperation("Toggle application visibility for university", tags = ["University API"],
            authorizations = [Authorization(value = "basicAuth")])
    @RequestMapping(method = [RequestMethod.PUT], path = ["/uni/applications/{id}/visible"])
    fun toggleApplicationVisibility(@AuthenticationPrincipal user: UserDetails,
                                    @PathVariable id: Long): UniversityApplicationDetails {
        return universityMessagingService.toggleApplicationVisibility(user, id)
    }

    @ApiOperation("Get application received from student", tags = ["University API"],
            authorizations = [Authorization(value = "basicAuth")])
    @RequestMapping(method = [RequestMethod.GET], path = ["/uni/applications/{id}"])
    fun getApplication(@AuthenticationPrincipal user: UserDetails,
                                    @PathVariable id: Long): UniversityApplicationDetails {
        return universityMessagingService.getApplication(user, id)
    }

    @ApiOperation("Update application status", tags = ["University API"],
            authorizations = [Authorization(value = "basicAuth")])
    @RequestMapping(method = [RequestMethod.PUT], path = ["/uni/applications/{id}/status"])
    fun updateApplicationStatus(@AuthenticationPrincipal user: UserDetails,
                                    @PathVariable id: Long,
                                    @Valid @RequestBody updatedStatus: ApplicationStatusUpdate): UniversityApplicationDetails {
        return universityMessagingService.updateApplicationStatus(user, id, updatedStatus)
    }

当我删除上面列出的映射时，我在运行时看到另一个控制器的相同堆栈跟踪。

这个项目在 Kotlin 1.2.71 上运行完美。我非常感谢任何建议使其与 Kotlin 1.3.0 一起使用！下面列出了我的完整build.gradle。

请注意：

1. 我使用以下 JDK 编译和运行这个项目：

   java version "11" 2018-09-25 Java(TM) SE Runtime Environment 18.9
   (build 11+28) Java HotSpot(TM) 64-Bit Server VM 18.9 (build 11+28,
   mixed mode)
   

2. 我还不能更新 Spring Boot，因为项目中的类依赖于 Spring Boot 1.x。

build.gradle：

buildscript {
    ext.kotlin_version = '1.3.0' // Was '1.2.71'
    ext.spring_boot_version = '1.5.4.RELEASE'
    repositories {
        jcenter()
    }
    dependencies {
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version" // Required for Kotlin integration
        classpath "org.jetbrains.kotlin:kotlin-allopen:$kotlin_version"
        classpath "org.jetbrains.kotlin:kotlin-noarg:$kotlin_version"
        classpath "org.springframework.boot:spring-boot-gradle-plugin:$spring_boot_version"
    }
}

apply plugin: 'idea'
apply plugin: 'kotlin'
apply plugin: 'kotlin-allopen'
apply plugin: 'kotlin-noarg'
apply plugin: 'org.springframework.boot'
apply plugin: 'application'

allOpen {
    annotation("org.springframework.boot.autoconfigure.SpringBootApplication")
    annotation("org.springframework.stereotype.Service")
    annotation("org.springframework.context.annotation.Configuration")
}

noArg {
    annotation("javax.persistence.Entity")
}

jar {
    baseName = 'vindedu-api'
    version = '0.0.1'
}

repositories {
    jcenter()
}

dependencies {
    compile "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version" // Required for Kotlin integration
    compile "org.jetbrains.kotlin:kotlin-reflect:$kotlin_version" // Required for Kotlin integration
    compile 'com.fasterxml.jackson.module:jackson-module-kotlin:2.9.2'
    compile 'org.springframework.boot:spring-boot-starter-security'
    compile 'org.springframework.boot:spring-boot-starter-web'
    compile 'org.springframework.boot:spring-boot-starter-data-jpa'
    compile 'org.springframework.boot:spring-boot-starter-actuator'
    compile 'org.springframework.session:spring-session:1.3.1.RELEASE'
    compile 'io.springfox:springfox-swagger2:2.7.0'
    compile 'io.springfox:springfox-swagger-ui:2.7.0'
    compile 'org.postgresql:postgresql:42.1.4'
    compile 'org.flywaydb:flyway-core:4.2.0'

    // JAXB dependencies don't ship with the JDK anymore
    compile 'javax.xml.bind:jaxb-api:2.3.1'
    compile 'com.sun.xml.bind:jaxb-impl:2.3.1'
    compile 'javax.activation:activation:1.1.1'

    testCompile 'org.springframework.boot:spring-boot-starter-test'
    testCompile 'com.h2database:h2:1.4.196'
}

task wrapper(type: Wrapper) {
    gradleVersion = '4.10.2'
}

springBoot {
    mainClass = 'com.vindedu.api.ApplicationKt'
}

bootRun {
    systemProperty("PROP_NAME", "prop-value")
}

test {
    maxParallelForks = Runtime.runtime.availableProcessors() / 3
}

Answer 1

从 1.3.0 开始，Kotlin 编译器不会为默认方法生成桥标志，并且仅在较新的 Spring Boot 版本中支持新的字节码。请升级到 Spring Boot 2。参考 issue：https://youtrack.jetbrains.com/issue/KT-27947