Demonstrate serialization and deserialization of lowercase enums using Jackson 2.6 onwards.

LowercaseEnumsWithJackson.java

import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;

import java.io.IOException;

/**
 * Demonstrate serialization and deserialization
 * of lowercase enums using Jackson 2.6 onwards.
 *
 * @author Andrew Bickerton
 */
public class LowercaseEnumsWithJackson {

    public static class Endpoint {

        public enum DataType {
            @JsonProperty("json")
            JSON,
            @JsonProperty("html")
            HTML
        }

        public String url;
        public DataType type;

        public Endpoint() {

        }

        @Override
        public String toString() {
            final StringBuilder sb = new StringBuilder("Endpoint{");
            sb.append("url='").append(url).append('\'');
            sb.append(", type=").append(type);
            sb.append('}');
            return sb.toString();
        }
    }

    private static ObjectMapper mapper = new ObjectMapper() {{
        configure(SerializationFeature.INDENT_OUTPUT, true);
    }};

    public static void main(String[] args) throws IOException {
        deserialize();
        serialize();
    }

    private static void deserialize() throws IOException {
        final String input = "{\"url\":\"foo\",\"type\":\"json\"}";
        final Endpoint endpoint = mapper.readValue(input, Endpoint.class);
        System.out.println("endpoint = " + endpoint);
    }

    private static void serialize() throws JsonProcessingException {
        final Endpoint endpoint = new Endpoint(){{
            url = "foo";
            type = DataType.JSON;
        }};

        final String output = mapper.writeValueAsString(endpoint);
        System.out.println("output = " + output);
    }
}