You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@camel.apache.org by "Claus Ibsen (JIRA)" <ji...@apache.org> on 2010/04/19 08:38:11 UTC
[jira] Updated: (CAMEL-2026) Enable async request-reply by
enhancing the CamelInvocationHandler so that it is serializable, so that
camel-spring Proxies can be passed as callback objects
[ https://issues.apache.org/activemq/browse/CAMEL-2026?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Claus Ibsen updated CAMEL-2026:
-------------------------------
Fix Version/s: Future
(was: 2.3.0)
> Enable async request-reply by enhancing the CamelInvocationHandler so that it is serializable, so that camel-spring Proxies can be passed as callback objects
> -------------------------------------------------------------------------------------------------------------------------------------------------------------
>
> Key: CAMEL-2026
> URL: https://issues.apache.org/activemq/browse/CAMEL-2026
> Project: Apache Camel
> Issue Type: Improvement
> Components: camel-core, camel-spring
> Affects Versions: 2.0.0
> Reporter: Scott Clasen
> Assignee: Claus Ibsen
> Fix For: Future
>
> Attachments: camel-2026.zip
>
>
> With minor alteration, the CamelInvocationHandler could be made serializable, and then camel-spring bean proxies could be passed as callback objects in method calls on other camel-spring proxies...enabling async request-reply via spring remoting.
> I have achieved this by Wrapping the CamelInvocationHandler, subclassing the CamelProxyFactoryBean, and by attaching a processor to routes that can recieve BeanInvocations that have a callback object. Integrated into the codebase, this could be much more straightforward, and not require a processor be attached.
> =================CamelInvocationHandlerWrapper
> {code}
> /**
> * Serializable wrapper for Camel/Spring remoting proxies.
> */
> public class CamelInvocationHandlerWrapper implements InvocationHandler, Serializable {
> /*
> Findbugs will complain that inner dosent get set at deserialization time. This is ok.
> You need to have a CamelRemotingProcessor in your inbound camel route that will reset the handler.
> */
> private transient CamelInvocationHandler inner;
> private String serviceUrl;
> private static final long serialVersionUID = 7635312279175935612L;
> /**
> * Create a CamelInvocationHandlerWrapper.
> *
> * @param handler the handler to use in this VM.
> * @param serviceUrl the serviceUrl to use to rebuild the CamelInvocationHandler if we are serialized and used in a different VM.
> */
> public CamelInvocationHandlerWrapper(CamelInvocationHandler handler, String serviceUrl) {
> this.inner = handler;
> this.serviceUrl = serviceUrl;
> }
> /**
> * {@inheritDoc}
> */
> public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
> if (method.getDeclaringClass().equals(Object.class)) {
> return method.invoke(this, args);
> } else {
> if (inner == null) {
> throw new IllegalStateException("The inner CamelInvocationHandler is null, perhaps there was no CamelRemotingProcessor on your inbound route???");
> } else {
> return inner.invoke(proxy, method, args);
> }
> }
> }
> /**
> * Package Private so the CamelRemotingProcessor can rewire when we are passed remotely.
> *
> * @param context the current camel context.
> * @throws Exception if we cant build an endpoint for the service url or create a producer.
> */
> void rebuildInvocationHandler(CamelContext context) throws Exception {
> Endpoint endpoint = CamelContextHelper.getMandatoryEndpoint(context, serviceUrl);
> Producer producer = endpoint.createProducer();
> producer.start();
> inner = new CamelInvocationHandler(endpoint, producer, new MethodInfoCache(endpoint.getCamelContext()));
> }
> void setServiceUrl(String serviceUrl) {
> this.serviceUrl = serviceUrl;
> }
> }
> {code}
> ================Proxy Factory
> {code}
> /**
> * ProxyFactory that wraps a camel proxy in a serializable form.
> */
> public class CamelProxyWrapperFactoryBean extends CamelProxyFactoryBean {
> /**
> * Override the CamelProxyFactoryBean to return a different proxy that uses a CamelInvocationHandlerWrapper.
> *
> * @return a Proxy backed by a CamelInvocationHandlerWrapper for the specified interface.
> * @throws Exception if we cant create the proxy.
> */
> @Override
> public Object getObject() throws Exception {
> Object proxy = super.getObject();
> CamelInvocationHandler handler = (CamelInvocationHandler) Proxy.getInvocationHandler(proxy);
> return Proxy.newProxyInstance(getObjectType().getClassLoader(), new Class[]{getObjectType()}, new CamelInvocationHandlerWrapper(handler, getServiceUrl()));
> }
> }
> {code}
> ========processor that "rewires" the transient CamelInvocationHandler by using the service url
> {code}
> public class CamelRemotingProcessor implements Processor {
> /**
> * Rebuild the CamelInvocationHandler if we were passed a Proxy that has a CamelInvocationHandlerWrapper as its handler.
> *
> * @param invocation the BeanInvocation whose args we check for the Proxy.
> * @param context the current Camel Context.
> * @throws Exception if something blows up.
> */
> public void rewireProxy(BeanInvocation invocation, CamelContext context) throws Exception {
> Object[] args = invocation.getArgs();
> if (args != null) {
> for (Object arg : args) {
> if (Proxy.isProxyClass(arg.getClass())) {
> InvocationHandler handler = Proxy.getInvocationHandler(arg);
> if (handler instanceof CamelInvocationHandlerWrapper) {
> CamelInvocationHandlerWrapper wrapper = (CamelInvocationHandlerWrapper) handler;
> wrapper.rebuildInvocationHandler(context);
> }
> }
> }
> }
> }
> /**
> * {@inheritDoc}
> */
> public void process(Exchange exchange) throws Exception {
> CamelContext context = exchange.getContext();
> BeanInvocation invocation = exchange.getIn().getBody(BeanInvocation.class);
> rewireProxy(invocation, context);
> }
> }
> {code}
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.