How do I use the Jersey JSON POJO support?

You can use @XmlRootElement if you want to use JAXB annotations (see other answers).

However, if you prefer pure POJO mapping, you must do the following (Unfortunately it isn't written in docs):

1. Add jackson*.jar to your classpath (As stated by @Vitali Bichov);
2. In web.xml, if you're using com.sun.jersey.config.property.packages init parameter, add org.codehaus.jackson.jaxrs to the list. This will include JSON providers in the scan list of Jersey.

Jersey-json has a JAXB implementation. The reason you're getting that exception is because you don't have a Provider registered, or more specifically a MessageBodyWriter. You need to register a proper context within your provider:

@Providerpublic class JAXBContextResolver implements ContextResolver<JAXBContext> {    private final static String ENTITY_PACKAGE = "package.goes.here";    private final static JAXBContext context;    static {        try {            context = new JAXBContextAdapter(new JSONJAXBContext(JSONConfiguration.mapped().rootUnwrapping(false).build(), ENTITY_PACKAGE));        } catch (final JAXBException ex) {            throw new IllegalStateException("Could not resolve JAXBContext.", ex);        }    }    public JAXBContext getContext(final Class<?> type) {        try {            if (type.getPackage().getName().contains(ENTITY_PACKAGE)) {                return context;            }        } catch (final Exception ex) {            // trap, just return null        }        return null;    }    public static final class JAXBContextAdapter extends JAXBContext {        private final JAXBContext context;        public JAXBContextAdapter(final JAXBContext context) {            this.context = context;        }        @Override        public Marshaller createMarshaller() {            Marshaller marshaller = null;            try {                marshaller = context.createMarshaller();                marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);            } catch (final PropertyException pe) {                return marshaller;            } catch (final JAXBException jbe) {                return null;            }            return marshaller;        }        @Override        public Unmarshaller createUnmarshaller() throws JAXBException {            final Unmarshaller unmarshaller = context.createUnmarshaller();            unmarshaller.setEventHandler(new DefaultValidationEventHandler());            return unmarshaller;        }        @Override        public Validator createValidator() throws JAXBException {            return context.createValidator();        }    }}

This looks up for an @XmlRegistry within the provided package name, which is a package that contains @XmlRootElement annotated POJOs.

@XmlRootElementpublic class Person {    private String firstName;    //getters and setters, etc.}

then create an ObjectFactory in the same package:

@XmlRegistrypublic class ObjectFactory {   public Person createNewPerson() {      return new Person();   }}

With the @Provider registered, Jersey should facilitate the marshalling for you in your resource:

@GET@Consumes(MediaType.APPLICATION_JSON)public Response doWork(Person person) {   // do work   return Response.ok().build();}

This did it for me - Jersey 2.3.1

In the web.xml file :

<servlet><servlet-name>Jersey Web Application</servlet-name><servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class><init-param><param-name>jersey.config.server.provider.packages</param-name><param-value><my webapp packages>;org.codehaus.jackson.jaxrs</param-value></init-param></servlet>

In the pom.xml file :

<dependency><groupId>org.glassfish.jersey.media</groupId><artifactId>jersey-media-json-jackson</artifactId><version>2.3.1</version></dependency>