com.ibm.websphere.batch.devframework.datastreams.bdsadapter

Class AbstractBatchDataStream

java.lang.Object

com.ibm.websphere.batch.devframework.datastreams.bdsadapter.AbstractBatchDataStream

All Implemented Interfaces:

com.ibm.batch.api.BatchDataStream

Direct Known Subclasses:

AbstractBatchDataInputStreamRecordMetrics, AbstractBatchDataOutputStreamRecordMetrics

public abstract class AbstractBatchDataStream
extends java.lang.Object
implements BatchDataStream

Base implementation of BatchDataStream.

Field Summary

Fields

Modifier and Type	Field and Description
protected java.lang.String	jobStepKey

Constructor Summary

Constructors

Constructor and Description
AbstractBatchDataStream()

Method Summary

Methods

Modifier and Type	Method and Description
abstract void	close() Close underlying implementation stream.
abstract java.lang.String	externalizeCheckpointInformation() This method is called just before a checkpoint is to be taken by the batch container.
java.lang.String	getJobstepId()
java.lang.String	getName() The getName method returns the logical name of the BDS that was received in the initialize method.
java.util.Properties	getProperties() The getProperties method returns the bds properties specified in the xJCL and received in the setProperties method.
protected java.lang.String	getProperty(java.lang.String key) Convenience method to return a property value.
protected java.lang.String	getRequiredProperty(java.util.Properties props, java.lang.String key)
protected java.lang.String	getRequiredProperty(java.lang.String key) Convenience method to return a property value.
protected abstract void	initialize(java.util.Properties props) This method is invoked during stream initialization.
void	initialize(java.lang.String name, java.lang.String jobstepId) Called during stream initialization.
void	intermediateCheckpoint() LREE calls this method after a checkpoint is taken This implementation does nothing; subclasses may override.
abstract void	internalizeCheckpointInformation(java.lang.String token) Parse restart token supplied by LREE.
java.lang.Boolean	isRestart()
protected java.lang.Object	loadClass(java.lang.String className)
abstract void	open() Opens delegate stream.
abstract void	positionAtInitialCheckpoint() Positions the stream to the initial checkpoint (i.e., the beginning of the stream).
void	setProperties(java.util.Properties props) LREE calls this method to tell us our properties as specified in the xJCL.
protected void	setRestart(boolean restart) Sets the 'restarting' flag on this BDS.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.ibm.websphere.batch.BatchDataStream

positionAtCurrentCheckpoint

Field Detail

jobStepKey

protected java.lang.String jobStepKey

Constructor Detail

AbstractBatchDataStream

public AbstractBatchDataStream()

Method Detail

close

public abstract void close()
                    throws BatchContainerDataStreamException

Close underlying implementation stream.

Specified by:

close in interface com.ibm.batch.api.BatchDataStream

Throws:

BatchContainerDataStreamException - Underlying implementation stream threw an exception in its close() method.

internalizeCheckpointInformation

public abstract void internalizeCheckpointInformation(java.lang.String token)
                                               throws java.lang.RuntimeException

Parse restart token supplied by LREE.
This implementation assumes the restart token is a record cound, parseable as an integer.

Specified by:

internalizeCheckpointInformation in interface com.ibm.batch.api.BatchDataStream

Parameters:

token - - This is a string that was created by the BDS that was returned to the Batch Execution Environment on the externalizeCheckpointInformation method. This String is opaque to anyone but the BDS, so only the BDS can interpret its content.

Throws:

java.lang.RuntimeException - Restart token could not be parsed as an integer.

open

public abstract void open()
                   throws BatchContainerDataStreamException

Opens delegate stream.

Specified by:

open in interface com.ibm.batch.api.BatchDataStream

Throws:

BatchContainerDataStreamException - Error opening delegate stream.

positionAtInitialCheckpoint

public abstract void positionAtInitialCheckpoint()
                                          throws BatchContainerDataStreamException

Positions the stream to the initial checkpoint (i.e., the beginning of the stream).
This implementation simply sets the record counter to zero. Overriding subclasses should call the parent implementation.

Specified by:

positionAtInitialCheckpoint in interface com.ibm.batch.api.BatchDataStream

Throws:

BatchContainerDataStreamException - Error positioning the stream.

initialize

protected abstract void initialize(java.util.Properties props)

This method is invoked during stream initialization. Properties specified in the xJCL are passed as input

Parameters:

props -

externalizeCheckpointInformation

public abstract java.lang.String externalizeCheckpointInformation()

This method is called just before a checkpoint is to be taken by the batch container. This allows the stream to save any information that can be used by the container in case of a restart.

Specified by:

externalizeCheckpointInformation in interface com.ibm.batch.api.BatchDataStream

Returns:

- This is a string that is created to record the BDS's position in the stream being processed. This String is opaque to anyone but the BDS, so only the BDS can interpret its content.

getJobstepId

public java.lang.String getJobstepId()

Returns:

Our job/step id.

getName

public java.lang.String getName()

Description copied from interface: BatchDataStream

The getName method returns the logical name of the BDS that was received in the initialize method.

Specified by:

getName in interface com.ibm.batch.api.BatchDataStream

Returns:

Our logical name as specified in the xJCL.

getProperties

public java.util.Properties getProperties()

Description copied from interface: BatchDataStream

The getProperties method returns the bds properties specified in the xJCL and received in the setProperties method.

Specified by:

getProperties in interface com.ibm.batch.api.BatchDataStream

Returns:

Our properties as specified in the xJCL.

getProperty

protected java.lang.String getProperty(java.lang.String key)

Convenience method to return a property value.

Parameters:

key - Property key.

Returns:

Property value.

getRequiredProperty

protected java.lang.String getRequiredProperty(java.lang.String key)

Convenience method to return a property value. Throws an exception if the property was not set, or was set to an empty value.

Parameters:

key - Property key.

Returns:

Property value.

Throws:

java.lang.RuntimeException - No value was specified for the given key.

getRequiredProperty

protected java.lang.String getRequiredProperty(java.util.Properties props,
                                   java.lang.String key)

initialize

public void initialize(java.lang.String name,
              java.lang.String jobstepId)
                throws BatchContainerDataStreamException

Called during stream initialization.

Specified by:

initialize in interface com.ibm.batch.api.BatchDataStream

Parameters:

name - the logical name of the BDS, this name is used to locate the resource in the job's xJCL.

jobstepId - an identifier that represents the step within the batch job that is being run. This id is used to locate the resource in the job's xJCL.

Throws:

BatchContainerDataStreamException

intermediateCheckpoint

public void intermediateCheckpoint()

LREE calls this method after a checkpoint is taken
This implementation does nothing; subclasses may override.

Specified by:

intermediateCheckpoint in interface com.ibm.batch.api.BatchDataStream

setProperties

public void setProperties(java.util.Properties props)

LREE calls this method to tell us our properties as specified in the xJCL.

Specified by:

setProperties in interface com.ibm.batch.api.BatchDataStream

Parameters:

props - Stream properties from xJCL.

isRestart

public java.lang.Boolean isRestart()

Returns:

• Boolean.FALSE if we are not restarting
• Boolean.TRUE if we are restarting
• null if not yet known

setRestart

protected void setRestart(boolean restart)

Sets the 'restarting' flag on this BDS. Should be called by subclasses, in their BatchDataStream.positionAtCurrentCheckpoint() (set to true) or BatchDataStream.positionAtInitialCheckpoint() (set to false) methods, respectively.

Parameters:

restart -

loadClass

protected java.lang.Object loadClass(java.lang.String className)