prajna.structure.stream

Class DataRecordStream

java.lang.Object

prajna.structure.stream.DataRecordStream

Direct Known Subclasses:

SaxRecordStream

public abstract class DataRecordStream
extends java.lang.Object

Stream which produces DataRecord objects. The DataRecordStream should not retain any records in memory, but simply transform any new record and push it to any listeners. This class includes an optional DataTemplate which should specify how to construct the DataRecords from the underlying data source. If using the template, the transformation should be similar or identical to the process used for a SemanticAccessor. The implementation should create DataRecord objects even if no template is defined. The DataRecordStream also contains an optional SemanticReasoner to augment the records.

Author:

Edward Swing

Constructor Summary

Constructors

Constructor and Description
DataRecordStream()

Method Summary

Methods

Modifier and Type	Method and Description
void	addListener(DataRecordListener listener) Add a listener to the set of listeners for this DataRecordStream
void	applyReasoner(DataRecord rec) Apply the reasoner to the data record.
protected void	fireRecordReceived(DataRecord rec) Send the DataRecord to all record listeners.
RecordReasoner	getReasoner() Get the semantic reasoner for this DataRecordStream
DataTemplate	getTemplate() Get the data template for this DataRecordStream.
abstract java.util.Set<java.lang.String>	getUnknownFields() Get the set of fields which this stream did not parse.
void	removeListener(DataRecordListener listener) Remove a listener from the set of listeners for this DataRecordStream
void	setConfig(java.io.InputStream inStream) Set the configuration information from an input stream.
abstract void	setInitParameters(java.util.Map<java.lang.String,java.lang.String> parameters) Set any initialization parameters required by this stream reader.
void	setReasoner(RecordReasoner semanticReasoner) Set the semantic reasoner for this DataRecordStream
void	setTemplate(DataTemplate dataTemplate) Set the data template for this DataRecordStream.

Methods inherited from class java.lang.Object

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

Constructor Detail

DataRecordStream

public DataRecordStream()

Method Detail

addListener

public void addListener(DataRecordListener listener)

Add a listener to the set of listeners for this DataRecordStream

Parameters:

listener - the listener to add

applyReasoner

public void applyReasoner(DataRecord rec)

Apply the reasoner to the data record. If the reasoner is not null, this method will use the reasoner to augment the data record.

Parameters:

rec - the record to apply the reasoner to.

fireRecordReceived

protected void fireRecordReceived(DataRecord rec)

Send the DataRecord to all record listeners. The DataRecordStream will send any DataRecord objects created. When the stream has finished processing data, it should send a null to this method.

Parameters:

rec - The DataRecord to send

getReasoner

public RecordReasoner getReasoner()

Get the semantic reasoner for this DataRecordStream

Returns:

the semantic reasoner, or null if the reasoner has not been set.

getTemplate

public DataTemplate getTemplate()

Get the data template for this DataRecordStream. The template is used to determine how the DataRecord should be configured and generated from the underlying data source.

Returns:

the data template

getUnknownFields

public abstract java.util.Set<java.lang.String> getUnknownFields()

Get the set of fields which this stream did not parse. This method may be used to identify parts of the stream transformation which are not translated properly

Returns:

the unknown fields

removeListener

public void removeListener(DataRecordListener listener)

Remove a listener from the set of listeners for this DataRecordStream

Parameters:

listener - the listener to remove

setConfig

public void setConfig(java.io.InputStream inStream)

Set the configuration information from an input stream. The input stream should contain any required initialization parameters. This method should initialize the data record stream if necessary. This implementation uses an XML-based configuration file.

Parameters:

inStream - Input stream which is the source of the configuration information

setInitParameters

public abstract void setInitParameters(java.util.Map<java.lang.String,java.lang.String> parameters)

Set any initialization parameters required by this stream reader.

Parameters:

parameters - a map of initialization parameters

setReasoner

public void setReasoner(RecordReasoner semanticReasoner)

Set the semantic reasoner for this DataRecordStream

Parameters:

semanticReasoner - the semantic reasoner

setTemplate

public void setTemplate(DataTemplate dataTemplate)

Set the data template for this DataRecordStream. The template is used to determine how the DataRecord should be configured and generated from the underlying data source. If the template is not set, the DataRecordStream should still generate DataRecord objects.

Parameters:

dataTemplate - the template to set