Question

我正在写一个宁静的服务，在我的控制器中返回对象，我的调度程序看起来像这样

<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

<servlet>
    <servlet-name>rest</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
    <servlet-name>rest</servlet-name>
    <url-pattern>/</url-pattern>
</servlet-mapping>

我的控制器看起来像这样

@RequestMapping(method = RequestMethod.GET, value = "/{bookmarkId}")
    Bookmark readBookmark(@PathVariable String userId, @PathVariable Long bookmarkId) {
        this.validateUser(userId);
        return this.bookmarkRepository.findOne(bookmarkId);
    }

在我的pom中我有

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-core</artifactId>
    <version>2.9.5</version>
</dependency>

我的问题是当我没有配置任何Http2messageconverter时它是如何将我的对象转换为json的，我的理解是http2messageconverter在我的pom中需要更快的xml以便将对象转换为json，所以为什么它没有我的jsonconverter的显式配置工作

Answer 1

这是因为在默认情况下，当你通过xml启用web mvc或者通过注释时，弹簧预启用下面列出的一些消息转换器，你也可以为其他转换器提供库，如果需要pr prefered

ByteArrayHttpMessageConverter – converts byte arrays
StringHttpMessageConverter – converts Strings
ResourceHttpMessageConverter – converts org.springframework.core.io.Resource for any type of octet stream
SourceHttpMessageConverter – converts javax.xml.transform.Source
FormHttpMessageConverter – converts form data to/from a MultiValueMap<String, String>.
Jaxb2RootElementHttpMessageConverter – converts Java objects to/from XML (added only if JAXB2 is present on the classpath)
MappingJackson2HttpMessageConverter – converts JSON (added only if Jackson 2 is present on the classpath)
MappingJacksonHttpMessageConverter – converts JSON (added only if Jackson is present on the classpath)
AtomFeedHttpMessageConverter – converts Atom feeds (added only if Rome is present on the classpath)
RssChannelHttpMessageConverter – converts RSS feeds (added only if Rome is present on the classpath)

为什么我的调度程序servlet中不需要http2MessageConverter

1 个答案: