HTTP message conversion

Understand the idea

Response-body methods return values to be written to the response instead of view names. A suitable converter can serialize products as JSON. RequestBody uses message conversion in the opposite direction. Returned type and media-type negotiation affect converter selection.

A concrete example

@RestController
class ProductApi { /* returns List<Product> */ }

In the application

See the independently runnable examples in Stage 28.

A JSON response does not need a Thymeleaf template.

See it in a working stage

• Stage 28: return the same products as JSON

Related concepts

• Spring bean
• Dependency injection