Jackson

Spring provides support for the Jackson JSON library.

MVC JSON views based on the Jackson library

MappingJackson2JsonView uses the Jackson library's ObjectMapper to display the contents of the response in JSON format. By default, all Map model contents (except for framework-specific classes) are encoded in JSON format. In cases where Map content needs to be filtered, you can specify a specific set of model attributes to encode using the modelKeys property. You can also use the extractValueFromSingleKeyModel property so that the value in single-key models is extracted and serialized directly rather than as a Model Attribute Map

You can customize the JSON mapping to your liking using the annotations provided by Jackson. If you need additional control, you can implement a custom ObjectMapper via the ObjectMapper property for cases where you need to specify custom JSON serializers and deserializers for specific types.

XML representations based on the Jackson library

MappingJackson2XmlView uses XmlMapper Jackson library XML extensions for displaying the response content as XML. If a model contains multiple records, you must explicitly set the object to be serialized using the modelKey bean property. If the model contains one record, it is serialized automatically.

You can customize the XML rendering as you wish using JAXB or the annotations provided by Jackson. If you need additional control, you can implement a custom XmlMapper through the ObjectMapper property in cases where the custom XML needs to provide serializers and deserializers for certain types.