org.osesb.messagepipeline.test.builtinstagesunittest
Class ExtractCDElementValuesPipelineStage

java.lang.Object
  org.osesb.messagepipeline.PipelineStage
      org.osesb.messagepipeline.builtinstages.XMLNodeExtractorPipelineStage
          org.osesb.messagepipeline.test.builtinstagesunittest.ExtractCDElementValuesPipelineStage

public class ExtractCDElementValuesPipelineStage
extends XMLNodeExtractorPipelineStage

ExtractCDElementValuesPipelineStage extends XMLNodeExtractorPipelineStage to extract the messageID attribute and the <title> and <price> elements and place their values in a MessagePipelineContext variable named stageName.sqlStatementName.sqlParameters as an Object[].

stageName is the name of the subsequent DatabaseUpdatePipelineStage and sqlStatementName is the name of the SQLStatement in the DatabaseUpdatePipelineStage.

The sqlParameters are used by the DatabaseUpdatePipelineStage as input to the parameterized update of the 'CDELEMENTS' table in the JDBCTEST tables.

Since:

Version .9

Field Summary

Fields inherited from class org.osesb.messagepipeline.PipelineStage

log, messagePipelineContext, nextStage, parentMessagePipeline, pipelineStageConfiguration, previousStage, thisClassName

Constructor Summary

ExtractCDElementValuesPipelineStage(MessagePipeline parentMessagePipeline, PipelineStageConfiguration pipelineStageConfiguration)
Creates a new instance of ExtractCDElementValuesPipelineStage.

Method Summary

static void	main(java.lang.String[] args) main() For testing and sandboxing.
boolean	runStage(EAIMessage eaiMessage) Run PipelineStage logic.

Methods inherited from class org.osesb.messagepipeline.builtinstages.XMLNodeExtractorPipelineStage

getExtractedNodes, getExtractedNodes

Methods inherited from class org.osesb.messagepipeline.PipelineStage

beingDroppedFromPool, commit, getMessagePipelineContext, getNextStage, getParentMessagePipeline, getPipelineStageConfiguration, getPreviousStage, handlePipelineException, handlePipelineException, logMessage, propagate, rollback, setNextStage, setOutputMessage, setPreviousStage, setResultMessage, stageProcessingComplete, stageProcessingStarting

Methods inherited from class java.lang.Object

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

Constructor Detail

ExtractCDElementValuesPipelineStage

public ExtractCDElementValuesPipelineStage(MessagePipeline parentMessagePipeline,
                                           PipelineStageConfiguration pipelineStageConfiguration)
                                    throws java.lang.Exception

Creates a new instance of ExtractCDElementValuesPipelineStage.

Parameters:

parentMessagePipeline - The MessagePipeline that constructed this PipelineStage.

pipelineStageConfiguration - A PipelineStageConfiguration for this PipelineStage.

Throws:

java.lang.Exception - if constructed with a null parentMessagePipeline or a null pipelineStageConfiguration.

Method Detail

runStage

public boolean runStage(EAIMessage eaiMessage)
                 throws PipelineStageException

Run PipelineStage logic.

The runStage() method expects an IXMLMessage with XML text as the payload.

ExtractCDElementValuesPipelineStage is configured with a stageConfiguration that is a StandardPipelineStageConfiguration that includes a XPathExpressionListConfiguration with one or more xpathExpressions, which are applied to the XML text of the EAIXMLMessage.

runStage() invokes it's ancestor to apply the xpathExpressions and extract the target Nodes. The ancestor method sets a MessagePipelineContext variable to the extracted Nodes. The variable is a Map named "stageName.extractedNodeMap", where 'stageName' is the name of the PipelineStage. The Map uses the name of the xpathExpression as the key and a Node[] of extracted Nodes as the value.

MessagePipeline invokes the runStage() method on each PipelineStage in the order they appear in the MessagePipelineConfiguration. More specifically, the MessagePipeline invokes the following PipelineStage methods:

1. stageProcessingStarting(): The PipelineStage should allocate resources needed by runStage() in this method.
2. runStage()(): Main PipelineStage logic. To propagate the results of runStage() to the next stage, a PipelineStage invokes setOutputMessage() and/or propagate() with the EAIMessage to be passed to the next stage. setOutputMessage() is usually one of the last statements in runStage(), but propagate() can be invoked at any point in the runStage() method. See setOutputMessage() and propagate().
3. commit(): If a PipeleineStageException is not thrown, then commit() is invoked to commit outstanding transactions. The 'transactionScope' PipelineStageConfiguration property controls how the commit() and rollback() methods are invoked. See the getTransactionScope() method in PipelineStageConfiguration for details.
4. rollback(): If a PipeleineStageException is thrown, then rollback() is invoked to rollback outstanding transactions. The 'transactionScope' PipelineStageConfiguration property controls how the commit() and rollback() methods are invoked. See the getTransactionScope() method in PipelineStageConfiguration for details.
5. stageProcessingComplete(): PipelineStage should release resources in this method. The MessagePipeline invokes stageProcessingComplete() after all PipelineStage transactions are committed or rolled back.

If a PipelineStage's runStage() method returns false, then pipeline processing terminates with that stage and subsequent stages are not run. However, returning false does not indicate an error to the MessagePipeline. Returning false from runStage() indicates that pipeline processing completed normally before the end of the pipeline was reached.

If a PipelineStage's runStage() method returns true, then the MessagePipeline runs the next stage.

When pipeline processing ends normally, without throwing a PipelineStageException, the MessagePipeline will commit outstanding transactions beginning with the first PipelineStage. The 'transactionScope' PipelineStageConfiguration property controls how the commit() and rollback() PipelineStage methods are invoked. See the getTransactionScope() method in PipelineStageConfiguration for details around configuring 'transactionScope' for PipelineStages.

If a PipelineStage's runStage() method throws a PipelineStageException, then pipeline processing terminates with that stage and subsequent stages are not run.

When pipeline processing ends with a PipelineStageException, the MessagePipeline will roll back outstanding transactions beginning with the PipelineStage that threw the Exception. The 'transactionScope' PipelineStageConfiguration property controls how the commit() and rollback() PipelineStage methods are invoked. See the getTransactionScope() method in PipelineStageConfiguration for details around configuring 'transactionScope' for PipelineStages.

Overrides:

runStage in class XMLNodeExtractorPipelineStage

Parameters:

eaiMessage - The EAI message, which is the output of the last PipeLineStage that invoked setOutputMessage(), or, if this is the first PiplelineStage, then this is the EAIMessage that the MessagePipeline was invoked with.

Returns:

true to continue pipeline processing or false to terminate pipeline processing.

Throws:

a - PipelineStageException if any errors occur.

PipelineStageException

main

public static void main(java.lang.String[] args)

main() For testing and sandboxing.

Parameters:

args - commandline arguments