Throwing exceptions on camel routes

[brett_brettl]

Hello,

I have a camel route (using version 1.6.0.0) where I am receiving some xml files and then sending them to different locations depending on their content. I am doing this using the choice statement and xpath to determine where each of the xml files belong. In the otherwise portion of my choice statement I collect all of the files that did not belong anywhere else.

<otherwise>
    <to uri="file:src/main/data/unrecognizedRequests?noop=true"></to>
</otherwise>

At this point I also want to throw an exception so that my onException portion of the route can pick up the event and record it with other errors. My problem is that I do not know how to write the xml configuration so that it will throw an error. So how would I write my otherwise statement above to also throw an exception? Thanks.

Edited by: brett on Jun 19, 2009 1:58 PM

[mielket]

See http://camel.apache.org/message-router.html:

Choice without otherwise

If you use a choice without adding an otherwise, any unmatched exchanges will be dropped by default. If you prefer to have an exception for an unmatched exchange, you can add a throwFault to the otherwise.

....otherwise().throwFault("No matching when clause found on choice block");

... and try

Also see

http://camel.apache.org/maven/camel-core/apidocs/org/apache/camel/model/ThrowFaultType.html

[brett_brettl]

I have tried using , however now I am getting a Type Conversion error.

org.apache.camel.NoTypeConversionAvailableException: No type converter available to convert from type: class org.apache.camel.impl.DefaultMessage to the required type: java.io.InputStream with value Message: org.apache.camel.CamelException: java.lang.Exception
        at org.apache.camel.impl.converter.DefaultTypeConverter.doConvertTo(DefaultTypeConverter.java:147)
        at org.apache.camel.impl.converter.DefaultTypeConverter.convertTo(DefaultTypeConverter.java:90)
        at org.apache.camel.impl.converter.DefaultTypeConverter.convertTo(DefaultTypeConverter.java:86)
        at org.apache.camel.impl.MessageSupport.getBody(MessageSupport.java:85)
        at org.apache.camel.impl.MessageSupport.getBody(MessageSupport.java:52)
        at org.apache.camel.component.http.DefaultHttpBinding.doWriteResponse(DefaultHttpBinding.java:122)
        at org.apache.camel.component.http.DefaultHttpBinding.doWriteFaultResponse(DefaultHttpBinding.java:95)
        at org.apache.camel.component.http.DefaultHttpBinding.writeResponse(DefaultHttpBinding.java:62)
        at org.apache.camel.component.jetty.CamelContinuationServlet.service(CamelContinuationServlet.java:76)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
        at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:502)
        at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:363)
        at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:766)
        at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:230)
        at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
        at org.mortbay.jetty.Server.handle(Server.java:324)
        at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:534)
        at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:879)
        at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:741)
        at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:207)
        at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:403)
        at org.mortbay.jetty.bio.SocketConnector$Connection.run(SocketConnector.java:228)
        at org.mortbay.jetty.security.SslSocketConnector$SslConnection.run(SslSocketConnector.java:636)
        at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:522)

I tried to look up how to create my own type converter to get around this. According to http://camel.apache.org/type-converter.html I can make a type converter by making a Converter class and method like the following:

@Converter
public class DefaultMessageConverter {

     @Converter
     public static InputStream toInputStream(DefaultMessage dm)  {
          return new ByteArrayInputStream(dm.getExchange().getIn().getBody().toString().getBytes());
     }
}

The directions also specify to add a file called TypeConverter to the directory META-INF/services/org/apache/camel/ and include the name of the package that my DefaultMessageConverter class is in. I did all of this but I sill get the exact same error. Are the directions listed at http://camel.apache.org/type-converter.html only for Camel 2.0 and not 1.6.0.0? Does anyone see any reason why my converter would not be picked up?

Brett

[davsclaus]

Hi

That is a bug.

I have created a ticket

https://issues.apache.org/activemq/browse/CAMEL-1739

You can use a Processor to throw the exception. Then its a real exception and should work better.

from(x)

...

.process(new MyExceptionThrower)

And then just throw your exception from this processor in the process method.

[davsclaus]

In Spring DSL then use

[brett_brettl]

Thanks, that worked.

Brett

Edited by: brett on Jun 22, 2009 6:21 PM