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问题描述

我正在尝试使用两种保存方法创建一个休息控制器。一个用于保存单个实体,一个用于保存实体列表。

@RequestMapping(method = [POST, PUT])
fun save(@RequestBody entity: T): T {
    return service.save(entity)
}

@RequestMapping(method = [POST, PUT])
fun save(@RequestBody entities: List<T>): List<T> {
    return service.save(entities)
}

但是,由于,我假设,类型擦除弹簧会引发以下异常。

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'requestMappingHandlerMapping' defined in class path resource [org/springframework/boot/autoconfigure/web/servlet/WebMvcAutoConfiguration$EnableWebMvcConfiguration.class]: Invocation of init method failed; nested exception is java.lang.IllegalStateException: Ambiguous mapping. Cannot map 'crudControllerImpl' method 
public final T dk.fitfit.send.mail.CrudController.save(T)
to {[/messages],methods=[POST || PUT]}: There is already 'crudControllerImpl' bean method
public final java.util.List<T> dk.fitfit.send.mail.CrudController.save2(java.util.List<? extends T>) mapped.
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1694) ~[spring-beans-5.0.10.RELEASE.jar:5.0.10.RELEASE]
...

有什么线索吗?

标签: springgenericskotlin

解决方案


这是因为您有相同的请求映射。Spring 无法根据请求负载区分请求 - 仅在方法、路径和标头上。您可以尝试从此处应用建议:Jackson mapping Object or list of Object based on json input

对于您的情况,它看起来像

@RequestMapping(method = [POST, PUT])
fun save(@RequestBody @JsonFormat(with = JsonFormat.Feature.ACCEPT_SINGLE_VALUE_AS_ARRAY) entities: List<T>): List<T> {
    return service.save(entities)
}

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