weka.knowledgeflow.steps

Class SetVariables

java.lang.Object

weka.knowledgeflow.steps.BaseStep

weka.knowledgeflow.steps.SetVariables

All Implemented Interfaces:

java.io.Serializable, BaseStepExtender, Step

@KFStep(name="SetVariables",
        category="Flow",
        toolTipText="Assign default values for static variables, if not already set, and for dynamic variables. Static variables are guaranteed to be available to all other steps at initialization as the Knowledge Flow makes sure that SetVariables is invoked first first. Dynamic variables can have their values set using the values of attributes from incoming instances. Dynamic variables are *not* guaranteed to be available to other steps in the flow - instead, they are intended for use by a directly connected \'Job\' step, which will execute a specified sub-flow for each \'variables\' data object received.",
        iconPath="weka/gui/knowledgeflow/icons/SetVariables.gif")
public class SetVariables
extends BaseStep

Step that can be used to set the values of environment variables for the flow being executed. Can be useful when testing flows that use environment variables (that would typically have values set appropriately at runtime in a production setting). This step is special in the sense the the Knowledge Flow checks for it and invokes its stepInit() method (thus setting variables) before initializing all other steps in the flow. It can also be used to set 'dynamic' variables based on the values of attributes in incoming instances. Dynamic variables are not guaranteed to be available to other steps in the same flow at runtime. Instead, they are meant to be used by a directly connected (via 'variables' connection) 'Job' step, which will execute a specified sub-flow for each 'variables' data object received.

Version:

$Revision: $

Author:

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

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	SEP1 Separators for internal variable specification
static java.lang.String	SEP2
static java.lang.String	SEP3

Constructor Summary

Constructors

Constructor and Description
SetVariables()

Method Summary

Modifier and Type	Method and Description
java.lang.String	getCustomEditorForStep() Return the fully qualified name of a custom editor component (JComponent) to use for editing the properties of the step.
java.lang.String	getDynamicVarsInternalRep()
java.util.List<java.lang.String>	getIncomingConnectionTypes() Get a list of incoming connection types that this step can accept.
java.util.List<java.lang.String>	getOutgoingConnectionTypes() Get a list of outgoing connection types that this step can produce.
java.lang.String	getVarsInternalRep() Get the variables to set (in internal representation)
static java.util.Map<java.lang.String,java.util.List<java.lang.String>>	internalDynamicToMap(java.lang.String internalRep)
static java.util.Map<java.lang.String,java.lang.String>	internalToMap(java.lang.String internalRep) Convert a string in the internal static variable representation to a map of variables + values
Instances	outputStructureForConnectionType(java.lang.String connectionName) If possible, get the output structure for the named connection type as a header-only set of instances.
void	processIncoming(Data data) Process an incoming data payload (if the step accepts incoming connections)
void	setDynamicVarsInternalRep(java.lang.String rep)
void	setVarsInternalRep(java.lang.String rep) Set the static variables to set (in internal representation)
void	stepInit() Initialize the step.

Methods inherited from class weka.knowledgeflow.steps.BaseStep

environmentSubstitute, getDefaultSettings, getInteractiveViewers, getInteractiveViewersImpls, getName, getStepManager, globalInfo, isResourceIntensive, isStopRequested, 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 Detail

SEP1

public static final java.lang.String SEP1

Separators for internal variable specification

See Also:

Constant Field Values

SEP2

public static final java.lang.String SEP2

See Also:

Constant Field Values

SEP3

public static final java.lang.String SEP3

See Also:

Constant Field Values

Constructor Detail

SetVariables

public SetVariables()

Method Detail

setVarsInternalRep

@ProgrammaticProperty
public void setVarsInternalRep(java.lang.String rep)

Set the static variables to set (in internal representation)

Parameters:

rep - the variables to set

getVarsInternalRep

public java.lang.String getVarsInternalRep()

Get the variables to set (in internal representation)

Returns:

the variables to set

setDynamicVarsInternalRep

@ProgrammaticProperty
public void setDynamicVarsInternalRep(java.lang.String rep)

getDynamicVarsInternalRep

public java.lang.String getDynamicVarsInternalRep()

stepInit

public void stepInit()
              throws WekaException

Initialize the step.

Throws:

WekaException - if a problem occurs during initialization

processIncoming

public void processIncoming(Data data)
                     throws WekaException

Description copied from class: BaseStep

Process an incoming data payload (if the step accepts incoming connections)

Specified by:

processIncoming in interface BaseStepExtender

Specified by:

processIncoming in interface Step

Overrides:

processIncoming in class BaseStep

Parameters:

data - the payload to process

Throws:

WekaException - if a problem occurs

getIncomingConnectionTypes

public java.util.List<java.lang.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 java.util.List<java.lang.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

outputStructureForConnectionType

public Instances outputStructureForConnectionType(java.lang.String connectionName)
                                           throws WekaException

Description copied from class: BaseStep

If possible, get the output structure for the named connection type as a header-only set of instances. Can return null if the specified connection type is not representable as Instances or cannot be determined at present.

Specified by:

outputStructureForConnectionType in interface Step

Overrides:

outputStructureForConnectionType in class BaseStep

Parameters:

connectionName - the name of the connection type to get the output structure for

Returns:

the output structure as a header-only Instances object

Throws:

WekaException - if a problem occurs

getCustomEditorForStep

public java.lang.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

internalDynamicToMap

public static java.util.Map<java.lang.String,java.util.List<java.lang.String>> internalDynamicToMap(java.lang.String internalRep)

internalToMap

public static java.util.Map<java.lang.String,java.lang.String> internalToMap(java.lang.String internalRep)

Convert a string in the internal static variable representation to a map of variables + values

Parameters:

internalRep - the variables in internal represenation

Returns:

a map of variables + values