@ResponseBody and Enums

[DTechen]

Hi All,

I'm currently using @ResponseBody to return some JSON data for a number of REST calls. One of the calls does return a list of enums which is also automatically converted to JSON:

Controller

@Controller
@RequestMapping("/test")
public class RestController {
	
	/**
	 * Register all binder for custom data types so these types
	 * can be extracted from incoming requests and values assigned
	 * to objects.
	 * @param binder
	 */
	@InitBinder
	public void initAllBinder(WebDataBinder binder) {
		
		// register handler for dates
		binder.registerCustomEditor(Date.class, new DatePropertyEditor());
		
		// register binder for report types
		binder.registerCustomEditor(ReportTypeEnum.class, new ReportTypePropertyEditor());
	}
	
	/**
	 * Method to return the list of report types
	 * @param request
	 * @param response
	 * @return
	 */
	@RequestMapping(value = "/findReportTypes", method = RequestMethod.GET)
	public @ResponseBody List<ReportTypeEnum> findReportTypes(HttpServletRequest request, HttpServletResponse response) {
		
		try {
			
			// ... return my List<ReportTypeEnum>
		
		} catch (RESTException e) {
			// ... do some error handling
		}
		
		return retVal;
	}
	
	// ...
}

My Enum looks as follows:

public enum ReportTypeEnum {
	
	SUMMARY("Summary Report"),
YEAR("Year end Report");
	
	// name of the report
	private String reportFullName;
	
	
	private ReportTypeEnum(String fname) {
		this.reportFullName = fname;
	}
	
	// ....
}

The JSON response currently only contains the ReportTypeEnum.name value. How can I have more control over what's actually being returned to the requestor? I'd like not only to return the ReportTypeEnum.name, but also the reportFullName.

Thanks in advance,
Daniel

[DTechen]

I've just found a solution myself. I had to implement a custom serialzer...

Serializer

public class ReportTypeEnumSerializer extends JsonSerializer<ReportTypeEnum> {
	
	private Logger log = Logger.getLogger(ReportTypeEnumSerializer.class);

	@Override
	public void serialize(ReportTypeEnum value, JsonGenerator generator,
			SerializerProvider provider) throws IOException,
			JsonProcessingException {
		
		// output the custom Json
		generator.writeStartObject();
		
		// the type
		generator.writeFieldName("type");
		generator.writeString(value.name());
		
		// the full name
		generator.writeFieldName("name");
		generator.writeString(value.getReportFullName());
		
		// end tag
		generator.writeEndObject();
	}
}

and tell the Enum so via some Annotation:

Enum

@JsonSerialize(using=ReportTypeEnumSerializer.class)
public enum ReportTypeEnum {
	
	SUMMARY("Summary Report"),
YEAR("Year end Report");
	
	// name of the report
	private String reportFullName;
	
	
	private ReportTypeEnum(String fname) {
		this.reportFullName = fname;
	}
	
	// ....
}

... and that's it. :-)