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Posted to users@camel.apache.org by uprooter <up...@gmail.com> on 2009/05/18 00:41:38 UTC
Why does my JMS message type changes ?
Hello All.
I have this DSL that routes messages from topic1 to topic2.
The messages on topic1 are marshaled POJOs and I can happily unmarshal
them.
from("topic1").unmarshal(jaxb).choice()
.when().method("mymethod","isStudent").to("topic2")
The problem is that when I forward them to topic2 the payload is lost and
instead of getting ActiveMQTextMessage I only get ActiveMQMessage without
the text payload and I cannot cast them to TextMessage anymore.
(like, if I do from("topic1").to("topic2") everything works great but
unmashalling drops my payload somewhere)
I don't want to marshal the data again. only to route them according to my
method.
Can you please help me figure this out?
Many thanks.
--
View this message in context: http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23588615.html
Sent from the Camel - Users mailing list archive at Nabble.com.
Re: Why does my JMS message type changes ?
Posted by Claus Ibsen <cl...@gmail.com>.
On Mon, May 18, 2009 at 5:26 PM, Willem Jiang <wi...@gmail.com> wrote:
> Hi,
>
> I have to admit the suggestion of Claus is more DSL friendly :)
> And I just did a quick test, the message header should be passed after
> the marshal or unmarshal DSL.
> The processor way that I suggest is you can write the a customer
> processor to handle the exchange.
> If you just want to convert the incoming message to a certain JAXB class
> instance you can do it this way
>
> public void process(Exchange exchange) {
> CamelContext context = exchange.getCamelContext();
> TypeConverter converter = context.getTypeConverter();
> Message inMessage = exchange.getIn();
> PurchaseOrder purchaseOrder =
> converter.convertTo(PurchaseOrder.class, inMessage.getBody());
> inMessage.setHeader("PuchaseOrder", pucheseOrder);
> }
>
> Then you can check this header in your bean method.
And all the code can be done in 1 line of code :)
exchange.getIn().setHeader("PurchaseOrder",
exchange.getIn().getBody(PurchaseOrder.class));
Camel will use the type convert when you supply the wanted type in the
getBody method.
>
> Willem
>
> Claus Ibsen wrote:
>> On Mon, May 18, 2009 at 3:46 PM, uprooter <up...@gmail.com> wrote:
>>> I'm trying to implement what Willem suggested.
>>> I'm trying to avoid unmarshaling the payload while still processing messages
>>> according to an unmarshalled data.
>>> In order to do so I need to create a copy of the message, unmarshal it. And
>>> transfer it to a processor.
>>> It just don't see how it fits in Java DSL.
>>> Can you please demonstrate that part of creating a copy. unmarshalling and
>>> transferring to a processor ?
>>
>> Maybe you can store a copy of the original payload and then route as before
>> and when you are ready restore the body with the original payload.
>>
>> Something like this:
>>
>> from(x)
>> // store the original payload in a exchange property so we can get it later
>> .setPropery("original", body())
>> // TODO: do the unmarshal and then content based router
>> // now when you are ready to use the original body to send to a topic
>> then you can restore it
>> .setBody(property("original")).to("activemq:topic:foo");
>>
>>
>> Or am I misunderstanding your use case?
>>
>>
>> BTW: In a Processor you have full power, so you can do the JAXB stuff there also
>>
>> public void process(Exchange exchange) {
>> JAXBDataFormat df = new JAXBDataFormat(....
>> // and then use df to unmarshal
>> }
>>
>> That gives you another option to try with.
>>
>>
>>> John.
>>>
>>>
>>> Claus Ibsen-2 wrote:
>>>> On Mon, May 18, 2009 at 10:53 AM, uprooter <up...@gmail.com> wrote:
>>>>> Many thanks to your both.
>>>>> If I understand correctly, I need to set a header on my message and this
>>>>> header will be attached to my message.
>>>> No you should in fact not. Keep what you got from the JMS topic in the
>>>> body.
>>>>
>>>> What Willem suggested is a "trick" in case you need to store something
>>>> as a kind of 2nd copy / backup you can use headers for that.
>>>>
>>>>
>>>> When you use JMS as the transport then you cannot send any kind of
>>>> data over JMS. In fact one must follow the JMS spec that have a set of
>>>> limitations.
>>>>
>>>> A JMS message can contain
>>>> - properties (is mapped to Camel IN headers)
>>>> - payload (is mapped to Camel IN body)
>>>>
>>>> The JMS properties can only be simple or primitive types such as:
>>>> String, Integer, etc.
>>>>
>>>> The JMS payload can be
>>>> - TextMessage (mapped to String)
>>>> - BytesMessage (mapped to byte[] and other kinds)
>>>> - ObjectMessage (mapped to Serializable)
>>>> etc.
>>>>
>>>> So when you route something to a JMS topic with
>>>> (.to("activemq:topic:topic2") Camel will look at the IN body class
>>>> type and determine the best kinda of JMS message to use.
>>>>
>>>> So if you want to force that to be TextMessage then you IN body class
>>>> type must by java.lang.String.
>>>>
>>>> Using .convertBodyTo(String) before sending to the JMS topic you can
>>>> enfore that.
>>>>
>>>>
>>>>
>>>>> Unfortunately,After trying hard, I couldn't figure out how to add the
>>>>> unmarshaled payload as header, and how to make my bean read that header.
>>>>>
>>>>> I tried something like :
>>>>> from("topic1").setHeader("Student").end()
>>>>> .choice()
>>>>> .when().method("mymethod","isstudent")
>>>>> .to("seda:a");
>>>>>
>>>>> But I can't find anywhere to put unmarshal() on the header.
>>>> No unmarshal works on BODY only. If you want to do that on a Header
>>>> then you must do than yourself from eg a Processor or regular POJO
>>>> class.
>>>>
>>>>
>>>>>
>>>>> Claus Ibsen-2 wrote:
>>>>>> On Mon, May 18, 2009 at 12:41 AM, uprooter <up...@gmail.com> wrote:
>>>>>>> Hello All.
>>>>>>> I have this DSL that routes messages from topic1 to topic2.
>>>>>>> The messages on topic1 are marshaled POJOs and I can happily unmarshal
>>>>>>> them.
>>>>>>> from("topic1").unmarshal(jaxb).choice()
>>>>>>>
>>>>>>> .when().method("mymethod","isStudent").to("topic2")
>>>>>>>
>>>>>>> The problem is that when I forward them to topic2 the payload is lost
>>>>>>> and
>>>>>>> instead of getting ActiveMQTextMessage I only get ActiveMQMessage
>>>>>>> without
>>>>>>> the text payload and I cannot cast them to TextMessage anymore.
>>>>>>> (like, if I do from("topic1").to("topic2") everything works great but
>>>>>>> unmashalling drops my payload somewhere)
>>>>>>>
>>>>>>> I don't want to marshal the data again. only to route them according to
>>>>>>> my
>>>>>>> method.
>>>>>>> Can you please help me figure this out?
>>>>>>> Many thanks.
>>>>>> As Willem pointed out you unmarshal the payload from topic1 to JAXB.
>>>>>> And JAXB is a Java Object (not text).
>>>>>> So when you send a JAXB object to a JMS destination (topic2) the JMS
>>>>>> API will use javax.jms.ObjectMessage as the payload type.
>>>>>>
>>>>>> If you want to store it as text then you must convert the payload back
>>>>>> to text. Either with marshal or convertBodyTo(String.class) etc.
>>>>>> Depending if the JAXB can reverse its operation.
>>>>>>
>>>>>>
>>>>>> Note: In Camel 2.0 we have added options to the JMS producer so you
>>>>>> can enfore a specify JMS type to use, eg.
>>>>>> .to("activemq:topic:topic2? jmsMessageType=Text");
>>>>>>
>>>>>> See more here from: Message Mapping between JMS and Camel
>>>>>> http://camel.apache.org/jms.html
>>>>>>
>>>>>>
>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> --
>>>>>>> View this message in context:
>>>>>>> http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23588615.html
>>>>>>> Sent from the Camel - Users mailing list archive at Nabble.com.
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> Claus Ibsen
>>>>>> Apache Camel Committer
>>>>>>
>>>>>> Open Source Integration: http://fusesource.com
>>>>>> Blog: http://davsclaus.blogspot.com/
>>>>>> Twitter: http://twitter.com/davsclaus
>>>>>>
>>>>>>
>>>>> --
>>>>> View this message in context:
>>>>> http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23593558.html
>>>>> Sent from the Camel - Users mailing list archive at Nabble.com.
>>>>>
>>>>>
>>>>
>>>>
>>>> --
>>>> Claus Ibsen
>>>> Apache Camel Committer
>>>>
>>>> Open Source Integration: http://fusesource.com
>>>> Blog: http://davsclaus.blogspot.com/
>>>> Twitter: http://twitter.com/davsclaus
>>>>
>>>>
>>> --
>>> View this message in context: http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23595896.html
>>> Sent from the Camel - Users mailing list archive at Nabble.com.
>>>
>>>
>>
>>
>>
>
>
--
Claus Ibsen
Apache Camel Committer
Open Source Integration: http://fusesource.com
Blog: http://davsclaus.blogspot.com/
Twitter: http://twitter.com/davsclaus
Re: Why does my JMS message type changes ?
Posted by Willem Jiang <wi...@gmail.com>.
Hi,
I have to admit the suggestion of Claus is more DSL friendly :)
And I just did a quick test, the message header should be passed after
the marshal or unmarshal DSL.
The processor way that I suggest is you can write the a customer
processor to handle the exchange.
If you just want to convert the incoming message to a certain JAXB class
instance you can do it this way
public void process(Exchange exchange) {
CamelContext context = exchange.getCamelContext();
TypeConverter converter = context.getTypeConverter();
Message inMessage = exchange.getIn();
PurchaseOrder purchaseOrder =
converter.convertTo(PurchaseOrder.class, inMessage.getBody());
inMessage.setHeader("PuchaseOrder", pucheseOrder);
}
Then you can check this header in your bean method.
Willem
Claus Ibsen wrote:
> On Mon, May 18, 2009 at 3:46 PM, uprooter <up...@gmail.com> wrote:
>> I'm trying to implement what Willem suggested.
>> I'm trying to avoid unmarshaling the payload while still processing messages
>> according to an unmarshalled data.
>> In order to do so I need to create a copy of the message, unmarshal it. And
>> transfer it to a processor.
>> It just don't see how it fits in Java DSL.
>> Can you please demonstrate that part of creating a copy. unmarshalling and
>> transferring to a processor ?
>
> Maybe you can store a copy of the original payload and then route as before
> and when you are ready restore the body with the original payload.
>
> Something like this:
>
> from(x)
> // store the original payload in a exchange property so we can get it later
> .setPropery("original", body())
> // TODO: do the unmarshal and then content based router
> // now when you are ready to use the original body to send to a topic
> then you can restore it
> .setBody(property("original")).to("activemq:topic:foo");
>
>
> Or am I misunderstanding your use case?
>
>
> BTW: In a Processor you have full power, so you can do the JAXB stuff there also
>
> public void process(Exchange exchange) {
> JAXBDataFormat df = new JAXBDataFormat(....
> // and then use df to unmarshal
> }
>
> That gives you another option to try with.
>
>
>> John.
>>
>>
>> Claus Ibsen-2 wrote:
>>> On Mon, May 18, 2009 at 10:53 AM, uprooter <up...@gmail.com> wrote:
>>>> Many thanks to your both.
>>>> If I understand correctly, I need to set a header on my message and this
>>>> header will be attached to my message.
>>> No you should in fact not. Keep what you got from the JMS topic in the
>>> body.
>>>
>>> What Willem suggested is a "trick" in case you need to store something
>>> as a kind of 2nd copy / backup you can use headers for that.
>>>
>>>
>>> When you use JMS as the transport then you cannot send any kind of
>>> data over JMS. In fact one must follow the JMS spec that have a set of
>>> limitations.
>>>
>>> A JMS message can contain
>>> - properties (is mapped to Camel IN headers)
>>> - payload (is mapped to Camel IN body)
>>>
>>> The JMS properties can only be simple or primitive types such as:
>>> String, Integer, etc.
>>>
>>> The JMS payload can be
>>> - TextMessage (mapped to String)
>>> - BytesMessage (mapped to byte[] and other kinds)
>>> - ObjectMessage (mapped to Serializable)
>>> etc.
>>>
>>> So when you route something to a JMS topic with
>>> (.to("activemq:topic:topic2") Camel will look at the IN body class
>>> type and determine the best kinda of JMS message to use.
>>>
>>> So if you want to force that to be TextMessage then you IN body class
>>> type must by java.lang.String.
>>>
>>> Using .convertBodyTo(String) before sending to the JMS topic you can
>>> enfore that.
>>>
>>>
>>>
>>>> Unfortunately,After trying hard, I couldn't figure out how to add the
>>>> unmarshaled payload as header, and how to make my bean read that header.
>>>>
>>>> I tried something like :
>>>> from("topic1").setHeader("Student").end()
>>>> .choice()
>>>> .when().method("mymethod","isstudent")
>>>> .to("seda:a");
>>>>
>>>> But I can't find anywhere to put unmarshal() on the header.
>>> No unmarshal works on BODY only. If you want to do that on a Header
>>> then you must do than yourself from eg a Processor or regular POJO
>>> class.
>>>
>>>
>>>>
>>>> Claus Ibsen-2 wrote:
>>>>> On Mon, May 18, 2009 at 12:41 AM, uprooter <up...@gmail.com> wrote:
>>>>>> Hello All.
>>>>>> I have this DSL that routes messages from topic1 to topic2.
>>>>>> The messages on topic1 are marshaled POJOs and I can happily unmarshal
>>>>>> them.
>>>>>> from("topic1").unmarshal(jaxb).choice()
>>>>>>
>>>>>> .when().method("mymethod","isStudent").to("topic2")
>>>>>>
>>>>>> The problem is that when I forward them to topic2 the payload is lost
>>>>>> and
>>>>>> instead of getting ActiveMQTextMessage I only get ActiveMQMessage
>>>>>> without
>>>>>> the text payload and I cannot cast them to TextMessage anymore.
>>>>>> (like, if I do from("topic1").to("topic2") everything works great but
>>>>>> unmashalling drops my payload somewhere)
>>>>>>
>>>>>> I don't want to marshal the data again. only to route them according to
>>>>>> my
>>>>>> method.
>>>>>> Can you please help me figure this out?
>>>>>> Many thanks.
>>>>> As Willem pointed out you unmarshal the payload from topic1 to JAXB.
>>>>> And JAXB is a Java Object (not text).
>>>>> So when you send a JAXB object to a JMS destination (topic2) the JMS
>>>>> API will use javax.jms.ObjectMessage as the payload type.
>>>>>
>>>>> If you want to store it as text then you must convert the payload back
>>>>> to text. Either with marshal or convertBodyTo(String.class) etc.
>>>>> Depending if the JAXB can reverse its operation.
>>>>>
>>>>>
>>>>> Note: In Camel 2.0 we have added options to the JMS producer so you
>>>>> can enfore a specify JMS type to use, eg.
>>>>> .to("activemq:topic:topic2? jmsMessageType=Text");
>>>>>
>>>>> See more here from: Message Mapping between JMS and Camel
>>>>> http://camel.apache.org/jms.html
>>>>>
>>>>>
>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> View this message in context:
>>>>>> http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23588615.html
>>>>>> Sent from the Camel - Users mailing list archive at Nabble.com.
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Claus Ibsen
>>>>> Apache Camel Committer
>>>>>
>>>>> Open Source Integration: http://fusesource.com
>>>>> Blog: http://davsclaus.blogspot.com/
>>>>> Twitter: http://twitter.com/davsclaus
>>>>>
>>>>>
>>>> --
>>>> View this message in context:
>>>> http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23593558.html
>>>> Sent from the Camel - Users mailing list archive at Nabble.com.
>>>>
>>>>
>>>
>>>
>>> --
>>> Claus Ibsen
>>> Apache Camel Committer
>>>
>>> Open Source Integration: http://fusesource.com
>>> Blog: http://davsclaus.blogspot.com/
>>> Twitter: http://twitter.com/davsclaus
>>>
>>>
>> --
>> View this message in context: http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23595896.html
>> Sent from the Camel - Users mailing list archive at Nabble.com.
>>
>>
>
>
>
Re: Why does my JMS message type changes ?
Posted by uprooter <up...@gmail.com>.
That's what I was looking for.Works great.
Many thanks for your kind help.
PS.
I'm using maven builds of 2.0-m1 and the camel-jms is missing. It took me a
while to figure that out.
If you know of any other missing artifacts please announce.
You'll hear for me soon with some other problems :)
Claus Ibsen-2 wrote:
>
> On Mon, May 18, 2009 at 3:46 PM, uprooter <up...@gmail.com> wrote:
>>
>> I'm trying to implement what Willem suggested.
>> I'm trying to avoid unmarshaling the payload while still processing
>> messages
>> according to an unmarshalled data.
>> In order to do so I need to create a copy of the message, unmarshal it.
>> And
>> transfer it to a processor.
>> It just don't see how it fits in Java DSL.
>> Can you please demonstrate that part of creating a copy. unmarshalling
>> and
>> transferring to a processor ?
>
> Maybe you can store a copy of the original payload and then route as
> before
> and when you are ready restore the body with the original payload.
>
> Something like this:
>
> from(x)
> // store the original payload in a exchange property so we can get it
> later
> .setPropery("original", body())
> // TODO: do the unmarshal and then content based router
> // now when you are ready to use the original body to send to a topic
> then you can restore it
> .setBody(property("original")).to("activemq:topic:foo");
>
>
> Or am I misunderstanding your use case?
>
>
> BTW: In a Processor you have full power, so you can do the JAXB stuff
> there also
>
> public void process(Exchange exchange) {
> JAXBDataFormat df = new JAXBDataFormat(....
> // and then use df to unmarshal
> }
>
> That gives you another option to try with.
>
>
>>
>> John.
>>
>>
>> Claus Ibsen-2 wrote:
>>>
>>> On Mon, May 18, 2009 at 10:53 AM, uprooter <up...@gmail.com> wrote:
>>>>
>>>> Many thanks to your both.
>>>> If I understand correctly, I need to set a header on my message and
>>>> this
>>>> header will be attached to my message.
>>> No you should in fact not. Keep what you got from the JMS topic in the
>>> body.
>>>
>>> What Willem suggested is a "trick" in case you need to store something
>>> as a kind of 2nd copy / backup you can use headers for that.
>>>
>>>
>>> When you use JMS as the transport then you cannot send any kind of
>>> data over JMS. In fact one must follow the JMS spec that have a set of
>>> limitations.
>>>
>>> A JMS message can contain
>>> - properties (is mapped to Camel IN headers)
>>> - payload (is mapped to Camel IN body)
>>>
>>> The JMS properties can only be simple or primitive types such as:
>>> String, Integer, etc.
>>>
>>> The JMS payload can be
>>> - TextMessage (mapped to String)
>>> - BytesMessage (mapped to byte[] and other kinds)
>>> - ObjectMessage (mapped to Serializable)
>>> etc.
>>>
>>> So when you route something to a JMS topic with
>>> (.to("activemq:topic:topic2") Camel will look at the IN body class
>>> type and determine the best kinda of JMS message to use.
>>>
>>> So if you want to force that to be TextMessage then you IN body class
>>> type must by java.lang.String.
>>>
>>> Using .convertBodyTo(String) before sending to the JMS topic you can
>>> enfore that.
>>>
>>>
>>>
>>>>
>>>> Unfortunately,After trying hard, I couldn't figure out how to add the
>>>> unmarshaled payload as header, and how to make my bean read that
>>>> header.
>>>>
>>>> I tried something like :
>>>> from("topic1").setHeader("Student").end()
>>>> .choice()
>>>> .when().method("mymethod","isstudent")
>>>> .to("seda:a");
>>>>
>>>> But I can't find anywhere to put unmarshal() on the header.
>>> No unmarshal works on BODY only. If you want to do that on a Header
>>> then you must do than yourself from eg a Processor or regular POJO
>>> class.
>>>
>>>
>>>>
>>>>
>>>> Claus Ibsen-2 wrote:
>>>>>
>>>>> On Mon, May 18, 2009 at 12:41 AM, uprooter <up...@gmail.com> wrote:
>>>>>>
>>>>>> Hello All.
>>>>>> I have this DSL that routes messages from topic1 to topic2.
>>>>>> The messages on topic1 are marshaled POJOs and I can happily
>>>>>> unmarshal
>>>>>> them.
>>>>>> from("topic1").unmarshal(jaxb).choice()
>>>>>>
>>>>>> .when().method("mymethod","isStudent").to("topic2")
>>>>>>
>>>>>> The problem is that when I forward them to topic2 the payload is lost
>>>>>> and
>>>>>> instead of getting ActiveMQTextMessage I only get ActiveMQMessage
>>>>>> without
>>>>>> the text payload and I cannot cast them to TextMessage anymore.
>>>>>> (like, if I do from("topic1").to("topic2") everything works great but
>>>>>> unmashalling drops my payload somewhere)
>>>>>>
>>>>>> I don't want to marshal the data again. only to route them according
>>>>>> to
>>>>>> my
>>>>>> method.
>>>>>> Can you please help me figure this out?
>>>>>> Many thanks.
>>>>>
>>>>> As Willem pointed out you unmarshal the payload from topic1 to JAXB.
>>>>> And JAXB is a Java Object (not text).
>>>>> So when you send a JAXB object to a JMS destination (topic2) the JMS
>>>>> API will use javax.jms.ObjectMessage as the payload type.
>>>>>
>>>>> If you want to store it as text then you must convert the payload back
>>>>> to text. Either with marshal or convertBodyTo(String.class) etc.
>>>>> Depending if the JAXB can reverse its operation.
>>>>>
>>>>>
>>>>> Note: In Camel 2.0 we have added options to the JMS producer so you
>>>>> can enfore a specify JMS type to use, eg.
>>>>> .to("activemq:topic:topic2? jmsMessageType=Text");
>>>>>
>>>>> See more here from: Message Mapping between JMS and Camel
>>>>> http://camel.apache.org/jms.html
>>>>>
>>>>>
>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> View this message in context:
>>>>>> http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23588615.html
>>>>>> Sent from the Camel - Users mailing list archive at Nabble.com.
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Claus Ibsen
>>>>> Apache Camel Committer
>>>>>
>>>>> Open Source Integration: http://fusesource.com
>>>>> Blog: http://davsclaus.blogspot.com/
>>>>> Twitter: http://twitter.com/davsclaus
>>>>>
>>>>>
>>>>
>>>> --
>>>> View this message in context:
>>>> http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23593558.html
>>>> Sent from the Camel - Users mailing list archive at Nabble.com.
>>>>
>>>>
>>>
>>>
>>>
>>> --
>>> Claus Ibsen
>>> Apache Camel Committer
>>>
>>> Open Source Integration: http://fusesource.com
>>> Blog: http://davsclaus.blogspot.com/
>>> Twitter: http://twitter.com/davsclaus
>>>
>>>
>>
>> --
>> View this message in context:
>> http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23595896.html
>> Sent from the Camel - Users mailing list archive at Nabble.com.
>>
>>
>
>
>
> --
> Claus Ibsen
> Apache Camel Committer
>
> Open Source Integration: http://fusesource.com
> Blog: http://davsclaus.blogspot.com/
> Twitter: http://twitter.com/davsclaus
>
>
--
View this message in context: http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23602654.html
Sent from the Camel - Users mailing list archive at Nabble.com.
Re: Why does my JMS message type changes ?
Posted by Claus Ibsen <cl...@gmail.com>.
On Mon, May 18, 2009 at 3:46 PM, uprooter <up...@gmail.com> wrote:
>
> I'm trying to implement what Willem suggested.
> I'm trying to avoid unmarshaling the payload while still processing messages
> according to an unmarshalled data.
> In order to do so I need to create a copy of the message, unmarshal it. And
> transfer it to a processor.
> It just don't see how it fits in Java DSL.
> Can you please demonstrate that part of creating a copy. unmarshalling and
> transferring to a processor ?
Maybe you can store a copy of the original payload and then route as before
and when you are ready restore the body with the original payload.
Something like this:
from(x)
// store the original payload in a exchange property so we can get it later
.setPropery("original", body())
// TODO: do the unmarshal and then content based router
// now when you are ready to use the original body to send to a topic
then you can restore it
.setBody(property("original")).to("activemq:topic:foo");
Or am I misunderstanding your use case?
BTW: In a Processor you have full power, so you can do the JAXB stuff there also
public void process(Exchange exchange) {
JAXBDataFormat df = new JAXBDataFormat(....
// and then use df to unmarshal
}
That gives you another option to try with.
>
> John.
>
>
> Claus Ibsen-2 wrote:
>>
>> On Mon, May 18, 2009 at 10:53 AM, uprooter <up...@gmail.com> wrote:
>>>
>>> Many thanks to your both.
>>> If I understand correctly, I need to set a header on my message and this
>>> header will be attached to my message.
>> No you should in fact not. Keep what you got from the JMS topic in the
>> body.
>>
>> What Willem suggested is a "trick" in case you need to store something
>> as a kind of 2nd copy / backup you can use headers for that.
>>
>>
>> When you use JMS as the transport then you cannot send any kind of
>> data over JMS. In fact one must follow the JMS spec that have a set of
>> limitations.
>>
>> A JMS message can contain
>> - properties (is mapped to Camel IN headers)
>> - payload (is mapped to Camel IN body)
>>
>> The JMS properties can only be simple or primitive types such as:
>> String, Integer, etc.
>>
>> The JMS payload can be
>> - TextMessage (mapped to String)
>> - BytesMessage (mapped to byte[] and other kinds)
>> - ObjectMessage (mapped to Serializable)
>> etc.
>>
>> So when you route something to a JMS topic with
>> (.to("activemq:topic:topic2") Camel will look at the IN body class
>> type and determine the best kinda of JMS message to use.
>>
>> So if you want to force that to be TextMessage then you IN body class
>> type must by java.lang.String.
>>
>> Using .convertBodyTo(String) before sending to the JMS topic you can
>> enfore that.
>>
>>
>>
>>>
>>> Unfortunately,After trying hard, I couldn't figure out how to add the
>>> unmarshaled payload as header, and how to make my bean read that header.
>>>
>>> I tried something like :
>>> from("topic1").setHeader("Student").end()
>>> .choice()
>>> .when().method("mymethod","isstudent")
>>> .to("seda:a");
>>>
>>> But I can't find anywhere to put unmarshal() on the header.
>> No unmarshal works on BODY only. If you want to do that on a Header
>> then you must do than yourself from eg a Processor or regular POJO
>> class.
>>
>>
>>>
>>>
>>> Claus Ibsen-2 wrote:
>>>>
>>>> On Mon, May 18, 2009 at 12:41 AM, uprooter <up...@gmail.com> wrote:
>>>>>
>>>>> Hello All.
>>>>> I have this DSL that routes messages from topic1 to topic2.
>>>>> The messages on topic1 are marshaled POJOs and I can happily unmarshal
>>>>> them.
>>>>> from("topic1").unmarshal(jaxb).choice()
>>>>>
>>>>> .when().method("mymethod","isStudent").to("topic2")
>>>>>
>>>>> The problem is that when I forward them to topic2 the payload is lost
>>>>> and
>>>>> instead of getting ActiveMQTextMessage I only get ActiveMQMessage
>>>>> without
>>>>> the text payload and I cannot cast them to TextMessage anymore.
>>>>> (like, if I do from("topic1").to("topic2") everything works great but
>>>>> unmashalling drops my payload somewhere)
>>>>>
>>>>> I don't want to marshal the data again. only to route them according to
>>>>> my
>>>>> method.
>>>>> Can you please help me figure this out?
>>>>> Many thanks.
>>>>
>>>> As Willem pointed out you unmarshal the payload from topic1 to JAXB.
>>>> And JAXB is a Java Object (not text).
>>>> So when you send a JAXB object to a JMS destination (topic2) the JMS
>>>> API will use javax.jms.ObjectMessage as the payload type.
>>>>
>>>> If you want to store it as text then you must convert the payload back
>>>> to text. Either with marshal or convertBodyTo(String.class) etc.
>>>> Depending if the JAXB can reverse its operation.
>>>>
>>>>
>>>> Note: In Camel 2.0 we have added options to the JMS producer so you
>>>> can enfore a specify JMS type to use, eg.
>>>> .to("activemq:topic:topic2? jmsMessageType=Text");
>>>>
>>>> See more here from: Message Mapping between JMS and Camel
>>>> http://camel.apache.org/jms.html
>>>>
>>>>
>>>>
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> View this message in context:
>>>>> http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23588615.html
>>>>> Sent from the Camel - Users mailing list archive at Nabble.com.
>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> Claus Ibsen
>>>> Apache Camel Committer
>>>>
>>>> Open Source Integration: http://fusesource.com
>>>> Blog: http://davsclaus.blogspot.com/
>>>> Twitter: http://twitter.com/davsclaus
>>>>
>>>>
>>>
>>> --
>>> View this message in context:
>>> http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23593558.html
>>> Sent from the Camel - Users mailing list archive at Nabble.com.
>>>
>>>
>>
>>
>>
>> --
>> Claus Ibsen
>> Apache Camel Committer
>>
>> Open Source Integration: http://fusesource.com
>> Blog: http://davsclaus.blogspot.com/
>> Twitter: http://twitter.com/davsclaus
>>
>>
>
> --
> View this message in context: http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23595896.html
> Sent from the Camel - Users mailing list archive at Nabble.com.
>
>
--
Claus Ibsen
Apache Camel Committer
Open Source Integration: http://fusesource.com
Blog: http://davsclaus.blogspot.com/
Twitter: http://twitter.com/davsclaus
Re: Why does my JMS message type changes ?
Posted by uprooter <up...@gmail.com>.
I'm trying to implement what Willem suggested.
I'm trying to avoid unmarshaling the payload while still processing messages
according to an unmarshalled data.
In order to do so I need to create a copy of the message, unmarshal it. And
transfer it to a processor.
It just don't see how it fits in Java DSL.
Can you please demonstrate that part of creating a copy. unmarshalling and
transferring to a processor ?
John.
Claus Ibsen-2 wrote:
>
> On Mon, May 18, 2009 at 10:53 AM, uprooter <up...@gmail.com> wrote:
>>
>> Many thanks to your both.
>> If I understand correctly, I need to set a header on my message and this
>> header will be attached to my message.
> No you should in fact not. Keep what you got from the JMS topic in the
> body.
>
> What Willem suggested is a "trick" in case you need to store something
> as a kind of 2nd copy / backup you can use headers for that.
>
>
> When you use JMS as the transport then you cannot send any kind of
> data over JMS. In fact one must follow the JMS spec that have a set of
> limitations.
>
> A JMS message can contain
> - properties (is mapped to Camel IN headers)
> - payload (is mapped to Camel IN body)
>
> The JMS properties can only be simple or primitive types such as:
> String, Integer, etc.
>
> The JMS payload can be
> - TextMessage (mapped to String)
> - BytesMessage (mapped to byte[] and other kinds)
> - ObjectMessage (mapped to Serializable)
> etc.
>
> So when you route something to a JMS topic with
> (.to("activemq:topic:topic2") Camel will look at the IN body class
> type and determine the best kinda of JMS message to use.
>
> So if you want to force that to be TextMessage then you IN body class
> type must by java.lang.String.
>
> Using .convertBodyTo(String) before sending to the JMS topic you can
> enfore that.
>
>
>
>>
>> Unfortunately,After trying hard, I couldn't figure out how to add the
>> unmarshaled payload as header, and how to make my bean read that header.
>>
>> I tried something like :
>> from("topic1").setHeader("Student").end()
>> .choice()
>> .when().method("mymethod","isstudent")
>> .to("seda:a");
>>
>> But I can't find anywhere to put unmarshal() on the header.
> No unmarshal works on BODY only. If you want to do that on a Header
> then you must do than yourself from eg a Processor or regular POJO
> class.
>
>
>>
>>
>> Claus Ibsen-2 wrote:
>>>
>>> On Mon, May 18, 2009 at 12:41 AM, uprooter <up...@gmail.com> wrote:
>>>>
>>>> Hello All.
>>>> I have this DSL that routes messages from topic1 to topic2.
>>>> The messages on topic1 are marshaled POJOs and I can happily unmarshal
>>>> them.
>>>> from("topic1").unmarshal(jaxb).choice()
>>>>
>>>> .when().method("mymethod","isStudent").to("topic2")
>>>>
>>>> The problem is that when I forward them to topic2 the payload is lost
>>>> and
>>>> instead of getting ActiveMQTextMessage I only get ActiveMQMessage
>>>> without
>>>> the text payload and I cannot cast them to TextMessage anymore.
>>>> (like, if I do from("topic1").to("topic2") everything works great but
>>>> unmashalling drops my payload somewhere)
>>>>
>>>> I don't want to marshal the data again. only to route them according to
>>>> my
>>>> method.
>>>> Can you please help me figure this out?
>>>> Many thanks.
>>>
>>> As Willem pointed out you unmarshal the payload from topic1 to JAXB.
>>> And JAXB is a Java Object (not text).
>>> So when you send a JAXB object to a JMS destination (topic2) the JMS
>>> API will use javax.jms.ObjectMessage as the payload type.
>>>
>>> If you want to store it as text then you must convert the payload back
>>> to text. Either with marshal or convertBodyTo(String.class) etc.
>>> Depending if the JAXB can reverse its operation.
>>>
>>>
>>> Note: In Camel 2.0 we have added options to the JMS producer so you
>>> can enfore a specify JMS type to use, eg.
>>> .to("activemq:topic:topic2? jmsMessageType=Text");
>>>
>>> See more here from: Message Mapping between JMS and Camel
>>> http://camel.apache.org/jms.html
>>>
>>>
>>>
>>>>
>>>>
>>>>
>>>> --
>>>> View this message in context:
>>>> http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23588615.html
>>>> Sent from the Camel - Users mailing list archive at Nabble.com.
>>>>
>>>>
>>>
>>>
>>>
>>> --
>>> Claus Ibsen
>>> Apache Camel Committer
>>>
>>> Open Source Integration: http://fusesource.com
>>> Blog: http://davsclaus.blogspot.com/
>>> Twitter: http://twitter.com/davsclaus
>>>
>>>
>>
>> --
>> View this message in context:
>> http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23593558.html
>> Sent from the Camel - Users mailing list archive at Nabble.com.
>>
>>
>
>
>
> --
> Claus Ibsen
> Apache Camel Committer
>
> Open Source Integration: http://fusesource.com
> Blog: http://davsclaus.blogspot.com/
> Twitter: http://twitter.com/davsclaus
>
>
--
View this message in context: http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23595896.html
Sent from the Camel - Users mailing list archive at Nabble.com.
Re: Why does my JMS message type changes ?
Posted by Claus Ibsen <cl...@gmail.com>.
On Mon, May 18, 2009 at 10:53 AM, uprooter <up...@gmail.com> wrote:
>
> Many thanks to your both.
> If I understand correctly, I need to set a header on my message and this
> header will be attached to my message.
No you should in fact not. Keep what you got from the JMS topic in the body.
What Willem suggested is a "trick" in case you need to store something
as a kind of 2nd copy / backup you can use headers for that.
When you use JMS as the transport then you cannot send any kind of
data over JMS. In fact one must follow the JMS spec that have a set of
limitations.
A JMS message can contain
- properties (is mapped to Camel IN headers)
- payload (is mapped to Camel IN body)
The JMS properties can only be simple or primitive types such as:
String, Integer, etc.
The JMS payload can be
- TextMessage (mapped to String)
- BytesMessage (mapped to byte[] and other kinds)
- ObjectMessage (mapped to Serializable)
etc.
So when you route something to a JMS topic with
(.to("activemq:topic:topic2") Camel will look at the IN body class
type and determine the best kinda of JMS message to use.
So if you want to force that to be TextMessage then you IN body class
type must by java.lang.String.
Using .convertBodyTo(String) before sending to the JMS topic you can
enfore that.
>
> Unfortunately,After trying hard, I couldn't figure out how to add the
> unmarshaled payload as header, and how to make my bean read that header.
>
> I tried something like :
> from("topic1").setHeader("Student").end()
> .choice()
> .when().method("mymethod","isstudent")
> .to("seda:a");
>
> But I can't find anywhere to put unmarshal() on the header.
No unmarshal works on BODY only. If you want to do that on a Header
then you must do than yourself from eg a Processor or regular POJO
class.
>
>
> Claus Ibsen-2 wrote:
>>
>> On Mon, May 18, 2009 at 12:41 AM, uprooter <up...@gmail.com> wrote:
>>>
>>> Hello All.
>>> I have this DSL that routes messages from topic1 to topic2.
>>> The messages on topic1 are marshaled POJOs and I can happily unmarshal
>>> them.
>>> from("topic1").unmarshal(jaxb).choice()
>>>
>>> .when().method("mymethod","isStudent").to("topic2")
>>>
>>> The problem is that when I forward them to topic2 the payload is lost and
>>> instead of getting ActiveMQTextMessage I only get ActiveMQMessage without
>>> the text payload and I cannot cast them to TextMessage anymore.
>>> (like, if I do from("topic1").to("topic2") everything works great but
>>> unmashalling drops my payload somewhere)
>>>
>>> I don't want to marshal the data again. only to route them according to
>>> my
>>> method.
>>> Can you please help me figure this out?
>>> Many thanks.
>>
>> As Willem pointed out you unmarshal the payload from topic1 to JAXB.
>> And JAXB is a Java Object (not text).
>> So when you send a JAXB object to a JMS destination (topic2) the JMS
>> API will use javax.jms.ObjectMessage as the payload type.
>>
>> If you want to store it as text then you must convert the payload back
>> to text. Either with marshal or convertBodyTo(String.class) etc.
>> Depending if the JAXB can reverse its operation.
>>
>>
>> Note: In Camel 2.0 we have added options to the JMS producer so you
>> can enfore a specify JMS type to use, eg.
>> .to("activemq:topic:topic2? jmsMessageType=Text");
>>
>> See more here from: Message Mapping between JMS and Camel
>> http://camel.apache.org/jms.html
>>
>>
>>
>>>
>>>
>>>
>>> --
>>> View this message in context:
>>> http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23588615.html
>>> Sent from the Camel - Users mailing list archive at Nabble.com.
>>>
>>>
>>
>>
>>
>> --
>> Claus Ibsen
>> Apache Camel Committer
>>
>> Open Source Integration: http://fusesource.com
>> Blog: http://davsclaus.blogspot.com/
>> Twitter: http://twitter.com/davsclaus
>>
>>
>
> --
> View this message in context: http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23593558.html
> Sent from the Camel - Users mailing list archive at Nabble.com.
>
>
--
Claus Ibsen
Apache Camel Committer
Open Source Integration: http://fusesource.com
Blog: http://davsclaus.blogspot.com/
Twitter: http://twitter.com/davsclaus
Re: Why does my JMS message type changes ?
Posted by uprooter <up...@gmail.com>.
Many thanks to your both.
If I understand correctly, I need to set a header on my message and this
header will be attached to my message.
Unfortunately,After trying hard, I couldn't figure out how to add the
unmarshaled payload as header, and how to make my bean read that header.
I tried something like :
from("topic1").setHeader("Student").end()
.choice()
.when().method("mymethod","isstudent")
.to("seda:a");
But I can't find anywhere to put unmarshal() on the header.
Claus Ibsen-2 wrote:
>
> On Mon, May 18, 2009 at 12:41 AM, uprooter <up...@gmail.com> wrote:
>>
>> Hello All.
>> I have this DSL that routes messages from topic1 to topic2.
>> The messages on topic1 are marshaled POJOs and I can happily unmarshal
>> them.
>> from("topic1").unmarshal(jaxb).choice()
>>
>> .when().method("mymethod","isStudent").to("topic2")
>>
>> The problem is that when I forward them to topic2 the payload is lost and
>> instead of getting ActiveMQTextMessage I only get ActiveMQMessage without
>> the text payload and I cannot cast them to TextMessage anymore.
>> (like, if I do from("topic1").to("topic2") everything works great but
>> unmashalling drops my payload somewhere)
>>
>> I don't want to marshal the data again. only to route them according to
>> my
>> method.
>> Can you please help me figure this out?
>> Many thanks.
>
> As Willem pointed out you unmarshal the payload from topic1 to JAXB.
> And JAXB is a Java Object (not text).
> So when you send a JAXB object to a JMS destination (topic2) the JMS
> API will use javax.jms.ObjectMessage as the payload type.
>
> If you want to store it as text then you must convert the payload back
> to text. Either with marshal or convertBodyTo(String.class) etc.
> Depending if the JAXB can reverse its operation.
>
>
> Note: In Camel 2.0 we have added options to the JMS producer so you
> can enfore a specify JMS type to use, eg.
> .to("activemq:topic:topic2? jmsMessageType=Text");
>
> See more here from: Message Mapping between JMS and Camel
> http://camel.apache.org/jms.html
>
>
>
>>
>>
>>
>> --
>> View this message in context:
>> http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23588615.html
>> Sent from the Camel - Users mailing list archive at Nabble.com.
>>
>>
>
>
>
> --
> Claus Ibsen
> Apache Camel Committer
>
> Open Source Integration: http://fusesource.com
> Blog: http://davsclaus.blogspot.com/
> Twitter: http://twitter.com/davsclaus
>
>
--
View this message in context: http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23593558.html
Sent from the Camel - Users mailing list archive at Nabble.com.
Re: Why does my JMS message type changes ?
Posted by Claus Ibsen <cl...@gmail.com>.
On Mon, May 18, 2009 at 12:41 AM, uprooter <up...@gmail.com> wrote:
>
> Hello All.
> I have this DSL that routes messages from topic1 to topic2.
> The messages on topic1 are marshaled POJOs and I can happily unmarshal
> them.
> from("topic1").unmarshal(jaxb).choice()
> .when().method("mymethod","isStudent").to("topic2")
>
> The problem is that when I forward them to topic2 the payload is lost and
> instead of getting ActiveMQTextMessage I only get ActiveMQMessage without
> the text payload and I cannot cast them to TextMessage anymore.
> (like, if I do from("topic1").to("topic2") everything works great but
> unmashalling drops my payload somewhere)
>
> I don't want to marshal the data again. only to route them according to my
> method.
> Can you please help me figure this out?
> Many thanks.
As Willem pointed out you unmarshal the payload from topic1 to JAXB.
And JAXB is a Java Object (not text).
So when you send a JAXB object to a JMS destination (topic2) the JMS
API will use javax.jms.ObjectMessage as the payload type.
If you want to store it as text then you must convert the payload back
to text. Either with marshal or convertBodyTo(String.class) etc.
Depending if the JAXB can reverse its operation.
Note: In Camel 2.0 we have added options to the JMS producer so you
can enfore a specify JMS type to use, eg.
.to("activemq:topic:topic2? jmsMessageType=Text");
See more here from: Message Mapping between JMS and Camel
http://camel.apache.org/jms.html
>
>
>
> --
> View this message in context: http://www.nabble.com/Why-does-my-JMS-message-type-changes---tp23588615p23588615.html
> Sent from the Camel - Users mailing list archive at Nabble.com.
>
>
--
Claus Ibsen
Apache Camel Committer
Open Source Integration: http://fusesource.com
Blog: http://davsclaus.blogspot.com/
Twitter: http://twitter.com/davsclaus
Re: Why does my JMS message type changes ?
Posted by Willem Jiang <wi...@gmail.com>.
Hi,
This is because umarshal() turn the in message body into a JAXB object.
So you cant get the TextMessage as you want from("topic2").
If you don't want to marshal the JAXB object again, you can store the
JAXB object into as a message header, and check out the message header
in your bean's isStudent().
Willem
uprooter wrote:
> Hello All.
> I have this DSL that routes messages from topic1 to topic2.
> The messages on topic1 are marshaled POJOs and I can happily unmarshal
> them.
> from("topic1").unmarshal(jaxb).choice()
> .when().method("mymethod","isStudent").to("topic2")
>
> The problem is that when I forward them to topic2 the payload is lost and
> instead of getting ActiveMQTextMessage I only get ActiveMQMessage without
> the text payload and I cannot cast them to TextMessage anymore.
> (like, if I do from("topic1").to("topic2") everything works great but
> unmashalling drops my payload somewhere)
>
> I don't want to marshal the data again. only to route them according to my
> method.
> Can you please help me figure this out?
> Many thanks.
>
>
>