java ObjectMapper.readValue 可以返回空值吗？
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ObjectMapper.readValue can return null value?
提问by mik
ObjectMapper.readValue in Hymanson library does return null value. In what case does it return null object? It found that from codebase.
Hymanson 库中的 ObjectMapper.readValue 确实返回空值。在什么情况下它返回空对象？它从代码库中发现。
<dependency>
<groupId>org.codehaus.Hymanson</groupId>
<artifactId>Hymanson-mapper-asl</artifactId>
<version>1.9.9</version>
</dependency>
You can browse through ObjectMapper class to dig in more details
您可以浏览 ObjectMapper 类以深入了解更多细节
采纳答案by StaxMan
readValue()returns nullfor JSON input consisting of JSON value null.
It does not return nullfor any other case: missing input (for example) would be rewarded by an exception; and no deserializer produces nullby default.
readValue()返回null由 JSON value 组成的 JSON 输入null。它不会null在任何其他情况下返回：丢失的输入（例如）将获得异常奖励；并且null默认情况下没有解串器产生。
