cErrorHandler

cErrorHandler properties

Component Family	Exception
Function	cErrorHandler provides multiple strategies to deal with errors in a Route.
Purpose	cErrorHandler is used to process errors in the message routing.
Basic settings	Default Handler	This error handler does not support a dead letter queue and will return exceptions back to the caller.
		Set Maximum Redeliveries: select this check box to set the number of redeliveries in the Maximum Redeliveries (int) field.
		Set Redelivery Delay: select this check box to set the initial redelivery delay (in milliseconds) in the Redelivery Delay (long) field.
		Set Retry Attempted Log Level: select this check box to select the log level in the Level list for log messages when retries are attempted.
		Asynchronized Delayed Redelivery: select this check box to allow asynchronous delayed redelivery.
		More Configurations by Code: select this check box to enter codes in the Code box for further configuration.
	Dead Letter	This handler supports attempting to redeliver the message exchange a number of times before sending it to a dead letter endpoint.
		Dead Letter Uri: select this check box to define the endpoint of the dead letter queue. Other parameters share the same meaning as those of the default handler.
	Logging Handler	This handler logs the exceptions.
		Set Logger Name: select this check box to give a name to the logger in the Name field.
		Set Log Level: select this check box to decide the log level from the Level list.
Usage	cErrorHandler is used separately or as a middle or end component in a Route. If this component is used separately, it will handle errors in all sub-routes. If this component is used in the middle or end of a sub-route, it will only handle exceptions that happen in the components of this sub-route, either before or after the cErrorHandler.
Limitation	n/a

Scenario: Logging the exception thrown during a client/server talk

In this scenario, a Jetty server is started before a client browser requests access to it.
Then an exception is thrown at the server side and logged by cErrorHandler.

Dropping and linking the components

Drop the following components from the Palette onto the
workspace: cMessagingEndpoint, cErrorHandler and cProcessor, labelled as Jetty_Server, Error_Handler
and Throw_Exception respectively.
Link cMessagingEndpoint and cProcessor using a Row >
Route connection.

Configuring the components

Double-click cErrorHandler to open its Basic settings view in the Component tab.
Select Logging Handler to log the exceptions that are
thrown.
Double-click cMessagingEndpoint to open its Basic settings view in the Component tab.
In the Uri field, enter
jetty:http://localhost:8889/service to specify the Jetty
server.
Click Advanced settings for further setup.
In the Dependencies table, click the [+] button to add a line and select
jetty from the Camel
component list.
Double-click cProcessor to open its Basic settings view in the Component tab.
In the Code box, enter throw new Exception("server side error") to throw an exception.
Press Ctrl+S to save your Route.

Viewing code and executing the Route

Click the Code tab at the bottom of the design workspace
to check the generated code.

As shown above, the route starts from the endpoint Jetty_Server
and throws the exception of server side error via
cProcessor_1.
Press F6 to execute the Route.

The Jetty server has started.
Launch an Internet browser and enter
http://localhost:8889/service (the Jetty server URI
configured above) in the address bar to access the server.

As shown above, the request failed due to the server error.
Go to the Studio and check the results in the Run
tab.

As shown above, cErrorHandler has logged the exception
at the level of ERROR.

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Docs 5.x

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cErrorHandler – Docs for ESB 5.x