17.2. Pluggable JAXBContexts with ContextResolvers
We do not recommend using this feature unless you are familiar with the principles involved.
By default, RESTEasy creates and caches
JAXBContext instances per class type depending on the class you are marshalling or unmarshalling. If you do not want RESTEasy to create JAXBContexts, you can plug in your own by implementing an instance of javax.ws.rs.ext.ContextResolver.
public interface ContextResolver<T>
{
T getContext(Class<?> type);
}
@Provider
@Produces("application/xml")
public class MyJAXBContextResolver implements ContextResolver<JAXBContext>
{
JAXBContext getContext(Class<?> type)
{
if (type.equals(WhateverClassIsOverridedFor.class)) return JAXBContext.newInstance()...;
}
}
You must provide a
@Produces annotation to specify the types of media intended for the context. You must also implement ContextResolver<JAXBContext>. This helps the runtime match the correct context resolver. You must also annotate the ContextResolver class with @Provider.
There are several ways to make this
ContextResolver available.
- return it as a class or instance from a
javax.ws.rs.core.Applicationimplementation. - list it as a provider with
resteasy.providers. - let RESTEasy automatically scan for it within your
WARfile. (See the Configuration Guide for more details.) - add it manually via
ResteasyProviderFactory.getInstance().registerProvider(Class)orregisterProviderInstance(Object).
