Package weka.knowledgeflow.steps

Class Join

java.lang.Object

weka.knowledgeflow.steps.BaseStep

weka.knowledgeflow.steps.Join

All Implemented Interfaces:

Serializable, BaseStepExtender, Step

@KFStep(name="Join",
        category="Flow",
        toolTipText="Performs an inner join on two incoming datasets/instance streams (IMPORTANT: assumes that both datasets are sorted in ascending order of the key fields). If data is not sorted then usea Sorter step to sort both into ascending order of the key fields. Does not handle the case wherekeys are not unique in one or both inputs.",
        iconPath="weka/gui/knowledgeflow/icons/Join.gif")
public class Join
extends BaseStep

Step that performs an inner join on one or more key fields from two incoming batch or streaming datasets.

Version:

$Revision: $

Author:

Mark Hall (mhall{[at]}pentaho{[dot]}com)

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
static final String	KEY_SPEC_SEPARATOR	Separator used to separate first and second input key specifications

Constructor Summary

Constructors

Constructor	Description
Join()

Method Summary

Modifier and Type	Method	Description
List<String>	getConnectedInputNames()	Get the names of the connected steps as a list
String	getCustomEditorForStep()	Return the fully qualified name of a custom editor component (JComponent) to use for editing the properties of the step.
Instances	getFirstInputStructure()	Get the Instances structure being produced by the first input
List<String>	getIncomingConnectionTypes()	Get a list of incoming connection types that this step can accept.
String	getKeySpec()	Get the key specification (in internal format - k11,k12,...,k1nKEY_SPEC_SEPARATORk21,k22,...,k2n)
List<String>	getOutgoingConnectionTypes()	Get a list of outgoing connection types that this step can produce.
Instances	getSecondInputStructure()	Get the Instances structure being produced by the second input
void	processIncoming(Data data)	Process some incoming data
void	setKeySpec(String ks)	Set the key specification (in internal format - k11,k12,...,k1nKEY_SPEC_SEPARATORk21,k22,...,k2n)
void	stepInit()	Initialize the step

Methods inherited from class weka.knowledgeflow.steps.BaseStep

environmentSubstitute, getDefaultSettings, getInteractiveViewers, getInteractiveViewersImpls, getName, getStepManager, globalInfo, isResourceIntensive, isStopRequested, outputStructureForConnectionType, outputStructureForConnectionType, setName, setStepIsResourceIntensive, setStepManager, setStepMustRunSingleThreaded, start, stepMustRunSingleThreaded, stop

Methods inherited from class java.lang.Object

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

Field Details

KEY_SPEC_SEPARATOR

public static final String KEY_SPEC_SEPARATOR

Separator used to separate first and second input key specifications

See Also:

• Constant Field Values

Constructor Details

Join

public Join()

Method Details

setKeySpec

public void setKeySpec(String ks)

Set the key specification (in internal format - k11,k12,...,k1nKEY_SPEC_SEPARATORk21,k22,...,k2n)

Parameters:

ks - the keys specification

getKeySpec

public String getKeySpec()

Get the key specification (in internal format - k11,k12,...,k1nKEY_SPEC_SEPARATORk21,k22,...,k2n)

Returns:

the keys specification

getConnectedInputNames

public List<String> getConnectedInputNames()

Get the names of the connected steps as a list

Returns:

the names of the connected steps as a list

getFirstInputStructure

public Instances getFirstInputStructure()
                                 throws WekaException

Get the Instances structure being produced by the first input

Returns:

the Instances structure from the first input

Throws:

WekaException - if a problem occurs

getSecondInputStructure

public Instances getSecondInputStructure()
                                  throws WekaException

Get the Instances structure being produced by the second input

Returns:

the Instances structure from the second input

Throws:

WekaException - if a problem occurs

stepInit

public void stepInit()
              throws WekaException

Initialize the step

Throws:

WekaException - if a problem occurs

processIncoming

public void processIncoming(Data data)
                     throws WekaException

Process some incoming data

Specified by:

processIncoming in interface BaseStepExtender

Specified by:

processIncoming in interface Step

Overrides:

processIncoming in class BaseStep

Parameters:

data - the data to process

Throws:

WekaException - if a problem occurs

getIncomingConnectionTypes

public List<String> getIncomingConnectionTypes()

Get a list of incoming connection types that this step can accept. Ideally (and if appropriate), this should take into account the state of the step and any existing incoming connections. E.g. a step might be able to accept one (and only one) incoming batch data connection.

Returns:

a list of incoming connections that this step can accept given its current state

getOutgoingConnectionTypes

public List<String> getOutgoingConnectionTypes()

Get a list of outgoing connection types that this step can produce. Ideally (and if appropriate), this should take into account the state of the step and the incoming connections. E.g. depending on what incoming connection is present, a step might be able to produce a trainingSet output, a testSet output or neither, but not both.

Returns:

a list of outgoing connections that this step can produce

getCustomEditorForStep

public String getCustomEditorForStep()

Return the fully qualified name of a custom editor component (JComponent) to use for editing the properties of the step. This method can return null, in which case the system will dynamically generate an editor using the GenericObjectEditor

Specified by:

getCustomEditorForStep in interface Step

Overrides:

getCustomEditorForStep in class BaseStep

Returns:

the fully qualified name of a step editor component