Swagger Annotation to add a json example to the response class

You need to annotate your Rest method with @ApiResponses and @ApiResponse.

For example

@ApiResponses(value = { 
                        @ApiResponse(code = 200, message = "Successful retrieval of demand",responseContainer="List"),
                        @ApiResponse(code = 404, message = "Demand does not exist", response = Your Error response.class),
                        @ApiResponse(code = 500, message = "Internal server error", response = Your Error response.class) 
                    }
            )

Annotate your Json Response class with @ApiModel and its field with @ApiModelProperty like

@ApiModel(description = "Your comment")
public class Demand implements Serializable {

    private static final long serialVersionUID = 1L;

    
    @ApiModelProperty(notes = "Your comments", required = true, example = "example value")
    private String demandId;
}