org.springframework.jms.remoting

Class JmsInvokerServiceExporter

java.lang.Object

org.springframework.remoting.support.RemotingSupport

org.springframework.remoting.support.RemoteExporter

org.springframework.remoting.support.RemoteInvocationBasedExporter

org.springframework.jms.remoting.JmsInvokerServiceExporter

All Implemented Interfaces:

Aware, BeanClassLoaderAware, InitializingBean, SessionAwareMessageListener<Message>

public class JmsInvokerServiceExporter
extends RemoteInvocationBasedExporter
implements SessionAwareMessageListener<Message>, InitializingBean

JMS message listener that exports the specified service bean as a JMS service endpoint, accessible via a JMS invoker proxy.

Note that this class implements Spring's SessionAwareMessageListener interface, since it requires access to the active JMS Session. Hence, this class can only be used with message listener containers which support the SessionAwareMessageListener interface (e.g. Spring's DefaultMessageListenerContainer).

Thanks to James Strachan for the original prototype that this JMS invoker mechanism was inspired by!

Since:

2.0

Author:

Juergen Hoeller, James Strachan

See Also:

JmsInvokerClientInterceptor, JmsInvokerProxyFactoryBean

Field Summary

Fields

Modifier and Type	Field and Description
private boolean	ignoreInvalidRequests
private MessageConverter	messageConverter
private java.lang.Object	proxy

Fields inherited from class org.springframework.remoting.support.RemotingSupport

logger

Constructor Summary

Constructors

Constructor and Description
JmsInvokerServiceExporter()

Method Summary

Modifier and Type	Method and Description
void	afterPropertiesSet() Invoked by a BeanFactory after it has set all bean properties supplied (and satisfied BeanFactoryAware and ApplicationContextAware).
protected Message	createResponseMessage(Message request, Session session, RemoteInvocationResult result) Create the invocation result response message.
protected RemoteInvocation	onInvalidRequest(Message requestMessage) Callback that is invoked by readRemoteInvocation(Message) when it encounters an invalid request message.
void	onMessage(Message requestMessage, Session session) Callback for processing a received JMS message.
protected RemoteInvocation	readRemoteInvocation(Message requestMessage) Read a RemoteInvocation from the given JMS message.
void	setIgnoreInvalidRequests(boolean ignoreInvalidRequests) Set whether invalidly formatted messages should be discarded.
void	setMessageConverter(MessageConverter messageConverter) Specify the MessageConverter to use for turning request messages into RemoteInvocation objects, as well as RemoteInvocationResult objects into response messages.
protected void	writeRemoteInvocationResult(Message requestMessage, Session session, RemoteInvocationResult result) Send the given RemoteInvocationResult as a JMS message to the originator.

Methods inherited from class org.springframework.remoting.support.RemoteInvocationBasedExporter

getRemoteInvocationExecutor, invoke, invokeAndCreateResult, setRemoteInvocationExecutor

Methods inherited from class org.springframework.remoting.support.RemoteExporter

checkService, checkServiceInterface, getExporterName, getProxyForService, getService, getServiceInterface, setInterceptors, setRegisterTraceInterceptor, setService, setServiceInterface

Methods inherited from class org.springframework.remoting.support.RemotingSupport

getBeanClassLoader, overrideThreadContextClassLoader, resetThreadContextClassLoader, setBeanClassLoader

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

messageConverter

private MessageConverter messageConverter

ignoreInvalidRequests

private boolean ignoreInvalidRequests

proxy

private java.lang.Object proxy

Constructor Detail

JmsInvokerServiceExporter

public JmsInvokerServiceExporter()

Method Detail

setMessageConverter

public void setMessageConverter(MessageConverter messageConverter)

Specify the MessageConverter to use for turning request messages into RemoteInvocation objects, as well as RemoteInvocationResult objects into response messages.

Default is a SimpleMessageConverter, using a standard JMS javax.jms.ObjectMessage for each invocation / invocation result object.

Custom implementations may generally adapt Serializables into special kinds of messages, or might be specifically tailored for translating RemoteInvocation(Result)s into specific kinds of messages.

setIgnoreInvalidRequests

public void setIgnoreInvalidRequests(boolean ignoreInvalidRequests)

Set whether invalidly formatted messages should be discarded. Default is "true".

Switch this flag to "false" to throw an exception back to the listener container. This will typically lead to redelivery of the message, which is usually undesirable - since the message content will be the same (that is, still invalid).

afterPropertiesSet

public void afterPropertiesSet()

Description copied from interface: InitializingBean

Invoked by a BeanFactory after it has set all bean properties supplied (and satisfied BeanFactoryAware and ApplicationContextAware).

This method allows the bean instance to perform initialization only possible when all bean properties have been set and to throw an exception in the event of misconfiguration.

Specified by:

afterPropertiesSet in interface InitializingBean

onMessage

public void onMessage(Message requestMessage,
                      Session session)
               throws JMSException

Description copied from interface: SessionAwareMessageListener

Callback for processing a received JMS message.

Implementors are supposed to process the given Message, typically sending reply messages through the given Session.

Specified by:

onMessage in interface SessionAwareMessageListener<Message>

Parameters:

requestMessage - the received JMS message (never null)

session - the underlying JMS Session (never null)

Throws:

JMSException - if thrown by JMS methods

readRemoteInvocation

protected RemoteInvocation readRemoteInvocation(Message requestMessage)
                                         throws JMSException

Read a RemoteInvocation from the given JMS message.

Parameters:

requestMessage - current request message

Returns:

the RemoteInvocation object (or null in case of an invalid message that will simply be ignored)

Throws:

javax.jms.JMSException - in case of message access failure

JMSException

writeRemoteInvocationResult

protected void writeRemoteInvocationResult(Message requestMessage,
                                           Session session,
                                           RemoteInvocationResult result)
                                    throws JMSException

Send the given RemoteInvocationResult as a JMS message to the originator.

Parameters:

requestMessage - current request message

session - the JMS Session to use

result - the RemoteInvocationResult object

Throws:

javax.jms.JMSException - if thrown by trying to send the message

JMSException

createResponseMessage

protected Message createResponseMessage(Message request,
                                        Session session,
                                        RemoteInvocationResult result)
                                 throws JMSException

Create the invocation result response message.

The default implementation creates a JMS ObjectMessage for the given RemoteInvocationResult object. It sets the response's correlation id to the request message's correlation id, if any; otherwise to the request message id.

Parameters:

request - the original request message

session - the JMS session to use

result - the invocation result

Returns:

the message response to send

Throws:

javax.jms.JMSException - if creating the messsage failed

JMSException

onInvalidRequest

protected RemoteInvocation onInvalidRequest(Message requestMessage)
                                     throws JMSException

Callback that is invoked by readRemoteInvocation(Message) when it encounters an invalid request message.

The default implementation either discards the invalid message or throws a MessageFormatException - according to the "ignoreInvalidRequests" flag, which is set to "true" (that is, discard invalid messages) by default.

Parameters:

requestMessage - the invalid request message

Returns:

the RemoteInvocation to expose for the invalid request (typically null in case of an invalid message that will simply be ignored)

Throws:

javax.jms.JMSException - in case of the invalid request supposed to lead to an exception (instead of ignoring it)

JMSException

See Also:

readRemoteInvocation(Message), setIgnoreInvalidRequests(boolean)