HttpMessageConverter doesn't support typed collections [SPR-8381]

[spring-projects-issues]

David Parks opened SPR-8381 and commented

HttpMessageConverter can't support conversion to typed collections.

Example: Use JacksonJsonMessageConverter to convert a json string to a Collection<Pojo> objects.

Since only a Class<? extends T> is specified, there's no way to declare both the type (Pojo.class) and the object (Collection.class).

Jackson classes support this using a TypeReference class (see: http://wiki.fasterxml.com/JacksonInFiveMinutes#Data_Binding_with_Generics)

Also, MappingJacksonJsonMessageConverter (line 104) is using a deprecated method of the current release of Jackson.

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Affects: 3.0.5

Reference URL: http://stackoverflow.com/questions/6173182/spring-json-convert-a-typed-collection-like-listmypojo

Issue Links:

• Proper handling of parameterized types for @RequestBody parameters [SPR-9570] #14204 Proper handling of parameterized types for @RequestBody parameters ("is depended on by")
• Proper handling of parameterized types in RestTemplate [SPR-7023] #11685 Proper handling of parameterized types in RestTemplate
• HttpMessageConverter#write should support typed collections [SPR-13467] #18046 HttpMessageConverter#write should support typed collections

[spring-projects-issues]

delphi23 commented

Why the issue is not resolved until now?
I encounter the same problem on SpringMVC 3.1.1

[spring-projects-issues]

Rossen Stoyanchev commented

Linking to #11685 since a solution for the RestTemplate would likely involve a similar enhancement to the message converters.

[spring-projects-issues]

Rossen Stoyanchev commented

There is now a new GenericHttpMessageConverter that can read content given a java.lang.reflect.Type, which can be a ParameterizedType.

The new GenericHttpMessageConverter is implemented by the MappingJacksonMessageConverter and a new Jaxb2CollectionHttpMessageConverter that can read a generic Collection where the generic type is a JAXB type annotated with @XmlRootElement or @XmlType.