JacksonObjectMapperUtils for JSON conversion in Spring MVC

JacksonObjectMapperUtils.java

import org.codehaus.jackson.JsonParser;
import org.codehaus.jackson.JsonProcessingException;
import org.codehaus.jackson.Version;
import org.codehaus.jackson.map.DeserializationContext;
import org.codehaus.jackson.map.JsonDeserializer;
import org.codehaus.jackson.map.ObjectMapper;
import org.codehaus.jackson.map.module.SimpleModule;
import org.codehaus.jackson.node.ObjectNode;

public class JacksonObjectMapperUtils {

	public static ObjectMapper newObjectMapper() {
		ObjectMapper mapper = new ObjectMapper();
		SimpleModule module = new SimpleModule("json", new Version(1, 0, 0,
				null));
		module.addDeserializer(SampleConnection.class,
				new SampleConnectionDeserializer());
		module.addDeserializer(SampleAuthentication.class,
				new SampleAuthenticationDeserializer());
		mapper.registerModule(module);
		return mapper;
	}

	public static class SampleConnectionDeserializer extends
			JsonDeserializer<SampleConnection> {
		@Override
		public SampleConnection deserialize(JsonParser jp,
				DeserializationContext ctxt) throws IOException,
				JsonProcessingException {
			ObjectMapper mapper = (ObjectMapper) jp.getCodec();
			ObjectNode root = (ObjectNode) mapper.readTree(jp);
			SampleProtocolType type = SampleProtocolType.valueOf(root.get(
					"protocol").asText());

			switch (type) {
			case TCP:
				return mapper
						.readValue(root, SampleTCPConnection.class);
			case UDP:
				return mapper
						.readValue(root, SampleUDPConnection.class);
			default:
				throw new IllegalArgumentException("Invalid type: " + type);
			}
		}
	}

	public static class SampleAuthenticationDeserializer extends
			JsonDeserializer<SampleAuthentication> {
		@Override
		public SampleAuthentication deserialize(JsonParser jp,
				DeserializationContext ctxt) throws IOException,
				JsonProcessingException {
			ObjectMapper mapper = (ObjectMapper) jp.getCodec();
			ObjectNode root = (ObjectNode) mapper.readTree(jp);
			SampleAuthenticationType type = SampleAuthenticationType
					.valueOf(root.get("type").asText());

			switch (type) {
			case ANONYMOUS:
				return mapper.readValue(root,
						SampleAnonymousAuthentication.class);
			case PASSWORD:
				return mapper.readValue(root,
						SamplePasswordAuthentication.class);
			case CUSTOM:
				return mapper.readValue(root,
						SampleCustomAuthentication.class);
			default:
				throw new IllegalArgumentException("Invalid type: " + type);
			}
		}
	}

}

spring.xml

	<mvc:annotation-driven>
		<mvc:message-converters>
			<bean
				class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter">
				<property name="objectMapper">
					<bean class="package.JacksonObjectMapperUtils"
						factory-method="newObjectMapper" />
				</property>
			</bean>
		</mvc:message-converters>
	</mvc:annotation-driven>