uk.org.ogsadai.activity.transform
Class XSLTransformActivity

java.lang.Object
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  +--uk.org.ogsadai.activity.Activity
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        +--uk.org.ogsadai.activity.transform.XSLTransformActivity

public class XSLTransformActivity

extends Activity

An Activity to perform XSL-Transforms. The activity has two inputs and one output. The first input is the XML to be transformed, the second is the XSLT document. The result of applying the transformation is written to the output.

Note that this implementation stores the entire transformed result in memory, so the size of transform possible depends on available memory. For streamed transforms, an STX (Streaming Transformations for XML) activity implementation may be preferable.

For information on this activity see the OGSA-DAI user doc: OGSA-DAI/doc/interaction/activities/transform/xslTransform.html

Author:

The OGSA-DAI Project Team

Field Summary

private static java.lang.String	COPYRIGHT_NOTICE Copyright statement
private static DAILogger	LOG Logger object for logging in this class
private javax.xml.transform.TransformerFactory	mFactory Used to create transformers.
private BlockReader	mInputXML Activity input - XML to be transformed
private BlockReader	mInputXSLT Activity input - XSLT transformation
private BlockWriter	mOutput Activity output - transformed XML

Fields inherited from class uk.org.ogsadai.activity.Activity

mContext, mExternalInputs, mExternalOutputs, mInternalInputs, mInternalOutputs

Constructor Summary

XSLTransformActivity(org.w3c.dom.Element element)

Method Summary

void	initialise() This method should be overridden by subclasses to perform any initialisation they require before the process method invocations begin.
void	processBlock() Performs an iteration of the processing of an activity.

Methods inherited from class uk.org.ogsadai.activity.Activity

cleanUp, connectsTo, createOutputPipe, getActivityConfiguration, getActivityName, getCause, getName, getObservableStatus, getProperties, getSession, getStatus, hasActivityConfiguration, hasProperties, process, processFirst, setActivityName, setCompleted, setError

Methods inherited from class java.lang.Object

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

Field Detail

COPYRIGHT_NOTICE

private static final java.lang.String COPYRIGHT_NOTICE

Copyright statement

See Also:

Constant Field Values

LOG

private static final DAILogger LOG

Logger object for logging in this class

mInputXML

private BlockReader mInputXML

Activity input - XML to be transformed

mInputXSLT

private BlockReader mInputXSLT

Activity input - XSLT transformation

mOutput

private BlockWriter mOutput

Activity output - transformed XML

mFactory

private final javax.xml.transform.TransformerFactory mFactory

Used to create transformers.

Constructor Detail

XSLTransformActivity

public XSLTransformActivity(org.w3c.dom.Element element)
                     throws ActivitySpecificationException,
                            ActivityCreationException

Method Detail

initialise

public void initialise()
                throws ActivitySpecificationException,
                       ActivityExecutionException

Description copied from class: Activity

This method should be overridden by subclasses to perform any initialisation they require before the process method invocations begin. This might be used for setting up convenient fields to reference objects contained in the context. It shouldn't be used for opening resources. That should be done in processFirst.

Overrides:

initialise in class Activity

Throws:

ActivityExecutionException - If some system problem prevents the activity from initialising.

ActivitySpecificationException - If a problem with settings provided by a client prevents the activity from initialising.

processBlock

public void processBlock()

Description copied from class: Activity

Performs an iteration of the processing of an activity. This may involve reading a block of input data and writing a block of output data, or may involve some other kind of processing. When an activity is processed by the OGSA-DAI engine, this method will be invoked repeatedly until the activity either completes or stops due to an error or termination call. An implementation of this method should invoke the setCompleted method to indicate that processing is complete, or the setError method if an error occurs that will prevent the processing from completing.

Specified by:

processBlock in class Activity