edu.udo.cs.miningmart.m4
Interface Step

All Superinterfaces:

GraphicalM4Object, M4Data, M4Object

All Known Implementing Classes:

Step

public interface Step
extends GraphicalM4Object

Version:

$Id: Step.java,v 1.20 2006/09/27 14:59:57 euler Exp $

Author:

Timm Euler, Daniel Hakenjos

Method Summary

boolean	adaptOutputToChangedInput() Ensures that the output of this step reflects the current state of the input parameters.
void	addDatabaseObjectToTrash(java.lang.String objectName, java.lang.String schemaName, java.lang.String objectType) Helper method to store the information about a database object in the trash index
void	addParameterTuple(Parameter par) Adds a parameter to this step's parameter list on tuple level.
void	addPredecessor(Step step)
void	addReversingStep(Step reversingStep) The given step is linked as reversing step to this one.
void	addSuccessor(Step step) This method should only be called from the method Case.addStepDependency(Step, Step)!
void	addToTrash(M4Data m4data) This method should only be called by the compiler after a new M4 object has been created by calling a constructor.
boolean	belongsToChainOrSubChain(Chain theChain) This method returns TRUE if this Step belongs to the given Chain, or to a direct or indirect subchain of the given Chain.
java.lang.String	checkFeatureRemoval(Concept theInputConcept, Feature theFeature) This method checks if any problems with the validity of this step would occur if the given feature were removed from the given input concept of this step.
boolean	checkInputParameterEntries() This method checks, for the current set of values of input parameters in this step, whether they fulfill all parameter contraints.
boolean	checkOutputParameterEntries() This method checks, for the current set of values of output parameters in this step, whether they fulfill all parameter contraints.
Step	copy(Case newCase, Chain newChain)
void	createOutput(OpParam theOpParam, java.util.Collection theNames) This method must only be called if no output objects existed for this Step before!
Parameter	createParameterTuple(java.lang.String name, ParameterObject object, long number, int loopNumber, java.lang.String type) Creates a Parameter that will be connected to this Step.
boolean	createsConceptualOutput() Some steps, like those using evaluation operators, do not produce any output concept or attribute.
Parameter	createValueParameterTuple(java.lang.String value, java.lang.String datatype, java.lang.String name, long number, int loopNumber, java.lang.String type) Creates a Parameter and a Value that will be connected to this Step.
void	deleteDbTrash() This method takes care of deleting trash objects from the business data schema.
void	deleteM4Trash() This method realizes the M4Compiler's garbage collection on the objects created during compilation of this Step.
boolean	dependencyExists(Chain toChain) Checks if this step has a successor among any of the steps in the given chain, including steps in any direct or indirect subchain of the given chain.
java.util.Collection	getAllInputConcepts() This method returns all concepts that are input concept to this step's operator, even those that are attached to an input relation but not modelled by an input parameter.
java.util.Collection	getAllInputRelations() Returns all relations that are a parameter object of an input parameter of this Step.
java.util.Collection	getAllPredecessors()
long	getCaseId() Getter method.
java.util.Collection	getCorrespondingOutputFeatures(Concept theInputConcept, Feature theFeature) This method finds all features in the output concept of this step that correspond to the given feature in the given input concept of this step.
java.util.Collection	getCrossReferences()
java.util.Collection	getDependentReversingSteps() This method returns all steps that have been created automatically to reverse the attribute creation done by this step's operator.
java.util.Collection	getInputConceptsThatAreParameters() This method returns all concepts that are input concept to this step's operator.
BaseAttribute[][]	getKeysOfRelationshipAssertion() This method checks if this Step creates a relationship from or to its output concept.
int	getLoopCount() Getter method.
java.util.Collection	getM4Trash() Active getter for the compiler's M4 Trash information.
int	getMaximumNumberOfStepsSinceLastMaterialisation() Returns the greatest number of steps between this step and the last of its predecessors that materialises its output.
java.lang.String	getMultiStepCondition() Getter method.
long	getNumber() Getter method.
java.util.Collection	getOpParamsToSelectFeatureParamObjectsFrom(OpParam opParam) Whenever an input of type BaseAttribute or MultiColumnFeature is expected the possible Concepts the Features may come from are explicitly given by constraints.
Concept	getOutputConcept() Returns the output concept of this step, if it exists, and NULL otherwise.
java.util.Collection	getParameter(OpParam theOpParam, int loopNr) Returns the instance of the given OpParam that is currently set in this Step.
ParamDict	getParameterDictionary(boolean expectingAllParamsToExist) Returns the parameter dictionary of the step.
Parameter	getParameterTuple(java.lang.String name, int loopNr) Return the parameter (tuple) of this step with the given name and loop number.
java.util.Collection	getParameterTuples() Active getter for the parameters of this Step in tuple-wise form (not aggregated by OpParam arrays!).
java.util.Collection	getPossibleConceptsForParam(OpParam opParam) This method returns a Collection of Concepts from which the feature denoted by the given OpParam must be selected.
java.util.Collection	getPossibleInputConcepts() This method finds all Concepts that are either of type DB or are created as an output concept by a Step that precedes this Step in the chain.
java.util.Collection	getResultingDataModel() Returns a collection of concepts; these concepts represent the data model that the current Case produced up to this Step.
Step	getReversedStep() Returns the step whose feature construction is reversed by this step, or null if no such step exists.
ParameterObject	getSingleParameterObject(java.lang.String parameterName) Returns the parameter object of the first parameter tuple with the given name and loop number 0.
java.util.Collection	getSuccessors() Active getter for this Step's successors.
Case	getTheCase() Getter method.
Chain	getTheChain() Getter method.
Operator	getTheOperator() Active getter method.
void	handleOldInput() To be called after changing the input of this step; ensures that old output attributes are removed from a replaced input concept.
boolean	hasOnlyInputConceptsOfTypeDB() Returns true iff all input concepts of this step are of type DB.
boolean	hasPredecessorOutsideChain() This method returns TRUE if this Step has a direct predecessor that does not belong to the same chain, nor one of its subchains.
boolean	hasSuccessorOutsideChain() This method returns TRUE if this Step has a direct successor that does not belong to the same chain, nor one of its subchains.
boolean	inputChangeCanAffectOutput(OpParam theOpParam) Returns TRUE iff a change to the given input OpParam can have any effect on the output parameters of this Step.
boolean	isAttribToTakeFromFromConcept(OpParam theAttribOpParam, OpParam theRelationOpParam) Returns TRUE iff there is a constraint indicating that the feature parameter indicated by theAttribOpParam is to be taken from the FromConcept of the relation given by theRelationOpParam.
boolean	isAttribToTakeFromToConcept(OpParam theAttribOpParam, OpParam theRelationOpParam) Returns TRUE iff there is a constraint indicating that the feature parameter indicated by theAttribOpParam is to be taken from the ToConcept of the relation given by theRelationOpParam.
boolean	isCompiled() After a Step has been successfully compiled a flag in the M4 database is set, which is removed by the next garbage collection.
boolean	isContainedInInputConcept(OpParam outputFeature) This method must only be called for an output feature.
boolean	isLastStepProducingConceptualOutput() Returns TRUE iff this step has no successors or if it has only successors that do not produce conceptual output.
boolean	isRelationallyValid()
boolean	isSuccessorOf(Step previousStep) Returns TRUE if this Step is a direct or indirect successor of the given Step, according to the step transitions (step dependencies).
boolean	isVisible(Feature theFeature) This method returns TRUE iff the given Feature may be displayed in the input concept, or in a list of Features to choose from for a parameter.
boolean	materialisesOutput() Returns true iff this step's operator creates a columnset for the output concept that represents a table, not a view.
void	propagateOutputChanges() This method should be called after changing some outputs of this Step.
void	removeAllParameterTuples()
void	removeParameter(java.lang.String parName)
boolean	removeParameterTuple(Parameter par) Removes a parameter from this step's parameter list on tuple level.
void	removePredecessor() Removes the link to the specified Predecessor.
boolean	removeSuccessor(Step step) Removes a Step from this Step's Collection of dependent Steps.
boolean	removeSuccessor(java.lang.String name) Removes a Step from this Step's Collection of dependent Steps.
void	renameOutput(OpParam theOpParam, java.util.Collection theNames) This method changes the names of the output parameter objects; the latter are assumed to exist.
void	setCompiled() This method may only be called by the control structure!
void	setLoopCount(int lc) Setter method.
void	setMultiStepCondition(java.lang.String msc) Setter method.
void	setNumber(long nr) Setter method.
java.util.Map	setParameter(OpParam theOpParam, java.util.Collection theParameterObjects, int loopNr) Sets the parameter specified by the given OpParam.
void	setTheCase(Case myCase) Setter method.
void	setTheChain(Chain chain) Setter method.
void	setTheOperator(Operator theOp) Setter method.
void	updateOutput(OpParam theOpParam) This method must only be called if any input parameter of this Step was changed.
boolean	usesAggregation() Returns true iff this step aggregates rows of its input concept
boolean	usesLoopsForCoordination() This method returns TRUE if the coordinated parameters in this step (ab)use the loop mechanism for their coordination.

Methods inherited from interface edu.udo.cs.miningmart.m4.GraphicalM4Object

getPoint, setPoint

Methods inherited from interface edu.udo.cs.miningmart.m4.M4Data

deleteSoon, getDocumentation, getValidName, isDirty, isWaitingForDelete, setDocumentation

Methods inherited from interface edu.udo.cs.miningmart.m4.M4Object

doPrint, doPrint, equals, executeBusinessSingleValueSqlRead, executeBusinessSingleValueSqlReadL, executeBusinessSqlRead, executeBusinessSqlWrite, executeM4SingleValueSqlRead, executeM4SingleValueSqlReadL, executeM4SqlRead, executeM4SqlWrite, getCasePrintObject, getId, getM4Db, getM4ObjectFromCache, getName, getNextM4SequenceValue, isNew, load, print, putM4ObjectToCache, replaceSpacesInName, setId, setName, setNotNew

Method Detail

getTheOperator

Operator getTheOperator()

Active getter method.

Returns:

the M4 operator object related to this Step

setTheOperator

void setTheOperator(Operator theOp)

Setter method. There is no back-reference from Operator, so we do not need another primitive setter.

Parameters:

theOp - The new operator

getTheChain

Chain getTheChain()

Getter method.

Returns:

the Chain of this Step

setTheChain

void setTheChain(Chain chain)
                 throws M4Exception

Setter method.

Parameters:

chain - The new chain

Throws:

M4Exception

getCaseId

long getCaseId()

Getter method.

Returns:

the id

getNumber

long getNumber()

Getter method.

Returns:

the number

setTheCase

void setTheCase(Case myCase)
                throws M4Exception

Setter method.

Parameters:

myCase - The new case

Throws:

M4Exception

setNumber

void setNumber(long nr)

Setter method.

Parameters:

nr - the new step number

getLoopCount

int getLoopCount()

Getter method.

Returns:

the loop count

getMultiStepCondition

java.lang.String getMultiStepCondition()

Getter method.

Returns:

the multistep condition

addParameterTuple

void addParameterTuple(Parameter par)
                       throws M4Exception

Adds a parameter to this step's parameter list on tuple level.

Parameters:

par - the Parameter object representing the parameter tuple

Throws:

M4Exception

removeParameterTuple

boolean removeParameterTuple(Parameter par)
                             throws M4Exception

Removes a parameter from this step's parameter list on tuple level.

Parameters:

par - the Parameter object representing the parameter tuple

Returns:

true iff the object was part of the parameter list and could be removed

Throws:

M4Exception

removeAllParameterTuples

void removeAllParameterTuples()
                              throws M4Exception

Throws:

M4Exception

removeParameter

void removeParameter(java.lang.String parName)
                     throws M4Exception

Throws:

M4Exception

dependencyExists

boolean dependencyExists(Chain toChain)
                         throws M4Exception

Checks if this step has a successor among any of the steps in the given chain, including steps in any direct or indirect subchain of the given chain.

Parameters:

toChain - the given chain

Returns:

TRUE iff this step has a successor among any of the steps in the given chain.

Throws:

M4Exception

setLoopCount

void setLoopCount(int lc)
                  throws M4Exception

Setter method.

Parameters:

lc - the new loop count

Throws:

M4Exception

setMultiStepCondition

void setMultiStepCondition(java.lang.String msc)

Setter method.

Parameters:

msc - The new multistep condition

getAllInputConcepts

java.util.Collection getAllInputConcepts()
                                         throws M4Exception

This method returns all concepts that are input concept to this step's operator, even those that are attached to an input relation but not modelled by an input parameter.

Throws:

M4Exception

getInputConceptsThatAreParameters

java.util.Collection getInputConceptsThatAreParameters()
                                                       throws M4Exception

This method returns all concepts that are input concept to this step's operator. (For Join and other operators, there can be more than one input concept.) Note that concepts attached to an input relation are not returned!

Throws:

M4Exception

getAllInputRelations

java.util.Collection getAllInputRelations()
                                          throws M4Exception

Returns all relations that are a parameter object of an input parameter of this Step.

Returns:

a collection of relations

Throws:

M4Exception

getKeysOfRelationshipAssertion

BaseAttribute[][] getKeysOfRelationshipAssertion()
                                                 throws M4Exception

This method checks if this Step creates a relationship from or to its output concept. If no, null is returned. If yes, it checks whether the output concept and its features have been created yet. If yes, it returns the BaseAttributes that form the keys of the relationship in a two-dimensional array.

Returns:

a two-dimensional array of the BaseAttributes that are the keys of the relationship created by this Step, or null

Throws:

M4Exception

getOutputConcept

Concept getOutputConcept()
                         throws M4Exception

Returns the output concept of this step, if it exists, and NULL otherwise.

Returns:

a concept or NULL

Throws:

M4Exception

getTheCase

Case getTheCase()

Getter method.

Returns:

this step's case

getParameterTuples

java.util.Collection getParameterTuples()
                                        throws M4Exception

Active getter for the parameters of this Step in tuple-wise form (not aggregated by OpParam arrays!).

Returns:

Returns a Collection of Parameter objects

Throws:

M4Exception

getSuccessors

java.util.Collection getSuccessors()
                                   throws M4Exception

Active getter for this Step's successors.

Returns:

Collection of dependent Step objects

Throws:

M4Exception

addSuccessor

void addSuccessor(Step step)
                  throws M4Exception

This method should only be called from the method Case.addStepDependency(Step, Step)! Please use that method instead of this one, because it also efficiently reorders the steps! Adds a Step to this Step's Collection of dependent Steps.

Parameters:

step - the Step to add

Throws:

M4Exception

removeSuccessor

boolean removeSuccessor(Step step)
                        throws M4Exception

Removes a Step from this Step's Collection of dependent Steps.

Parameters:

step - the Step to remove

Returns:

true iff the Step was found in the Collection and could be successfully removed

Throws:

M4Exception

removeSuccessor

boolean removeSuccessor(java.lang.String name)
                        throws M4Exception

Removes a Step from this Step's Collection of dependent Steps.

Parameters:

name - the name of the step to remove

Returns:

true iff the Step was found in the Collection and could be successfully removed

Throws:

M4Exception

getParameterDictionary

ParamDict getParameterDictionary(boolean expectingAllParamsToExist)
                                 throws M4Exception

Returns the parameter dictionary of the step. It contains the parameter tuples that are currently known to this steps in aggregated form. A boolean parameter is used to specify whether the calling method expects all parameters of this step (as specified by this step's operator's OpParams) to exist already.

Parameters:

expectingAllParamsToExist - If true, the caller expects the step to be fully parameterised.

Returns:

ParamDict object for the current step

Throws:

M4Exception

getCrossReferences

java.util.Collection getCrossReferences()
                                        throws M4Exception

Returns:

a Collection of Step to Step dependencies for sequentializing all Steps before writing updates to the database.

Throws:

M4Exception

getM4Trash

java.util.Collection getM4Trash()
                                throws M4Exception

Active getter for the compiler's M4 Trash information.

Returns:

a Collection of M4Data objects created by the M4 compiler that have to be removed before this Step can be compiled anew.

Throws:

M4Exception

addToTrash

void addToTrash(M4Data m4data)
                throws M4Exception

This method should only be called by the compiler after a new M4 object has been created by calling a constructor.

Parameters:

m4data - the M4Data object to be added to the table M4TRASH_T for being garbage collected before compiling this Step or any of its predecessors.

Throws:

M4Exception

deleteM4Trash

void deleteM4Trash()
                   throws M4Exception

This method realizes the M4Compiler's garbage collection on the objects created during compilation of this Step.

Throws:

M4Exception

addDatabaseObjectToTrash

void addDatabaseObjectToTrash(java.lang.String objectName,
                              java.lang.String schemaName,
                              java.lang.String objectType)
                              throws M4Exception

Helper method to store the information about a database object in the trash index

Throws:

M4Exception

deleteDbTrash

void deleteDbTrash()
                   throws M4Exception

This method takes care of deleting trash objects from the business data schema.

Throws:

M4Exception

isCompiled

boolean isCompiled()
                   throws M4Exception

After a Step has been successfully compiled a flag in the M4 database is set, which is removed by the next garbage collection. This method checks, if this flag is set.

Returns:

true iff this Step has been successfully compiled and no garbage collection involving this Step has been run afterwards.

Throws:

M4Exception

setCompiled

void setCompiled()
                 throws M4Exception

This method may only be called by the control structure! It marks this Step as successfully compiled. This information is used when it is checked for succeeding Steps, if all of the dependent resources are already available.

Throws:

M4Exception

isSuccessorOf

boolean isSuccessorOf(Step previousStep)
                      throws M4Exception

Returns TRUE if this Step is a direct or indirect successor of the given Step, according to the step transitions (step dependencies).

Parameters:

previousStep - Possibly a predecessor of this step

Returns:

TRUE if this step is a direct or indirect successor of the given step

Throws:

M4Exception

usesLoopsForCoordination

boolean usesLoopsForCoordination()
                                 throws M4Exception

This method returns TRUE if the coordinated parameters in this step (ab)use the loop mechanism for their coordination.

Returns:

TRUE iff parameters of the coordinated parameter groups should be read and set using positive loop numbers.

Throws:

M4Exception

usesAggregation

boolean usesAggregation()
                        throws M4Exception

Returns true iff this step aggregates rows of its input concept

Returns:

Throws:

M4Exception

materialisesOutput

boolean materialisesOutput()
                           throws M4Exception

Returns true iff this step's operator creates a columnset for the output concept that represents a table, not a view.

Returns:

Throws:

M4Exception

hasOnlyInputConceptsOfTypeDB

boolean hasOnlyInputConceptsOfTypeDB()
                                     throws M4Exception

Returns true iff all input concepts of this step are of type DB.

Returns:

Throws:

M4Exception

getMaximumNumberOfStepsSinceLastMaterialisation

int getMaximumNumberOfStepsSinceLastMaterialisation()
                                                    throws M4Exception

Returns the greatest number of steps between this step and the last of its predecessors that materialises its output. If all direct predecessors materialise their output, or if this step uses only DB Concepts as inputs, 0 is returned. Otherwise the maximum of these results for the predecessors is increased by 1 and returned.

Throws:

M4Exception

createsConceptualOutput

boolean createsConceptualOutput()
                                throws M4Exception

Some steps, like those using evaluation operators, do not produce any output concept or attribute. For such steps this method returns FALSE, for all others it returns TRUE.

Throws:

M4Exception

isLastStepProducingConceptualOutput

boolean isLastStepProducingConceptualOutput()
                                            throws M4Exception

Returns TRUE iff this step has no successors or if it has only successors that do not produce conceptual output.

Throws:

M4Exception

isRelationallyValid

boolean isRelationallyValid()

copy

Step copy(Case newCase,
          Chain newChain)
          throws M4Exception

Throws:

M4Exception

addPredecessor

void addPredecessor(Step step)
                    throws M4Exception

Throws:

M4Exception

getAllPredecessors

java.util.Collection getAllPredecessors()
                                        throws M4Exception

Throws:

M4Exception

getDependentReversingSteps

java.util.Collection getDependentReversingSteps()
                                                throws M4Exception

This method returns all steps that have been created automatically to reverse the attribute creation done by this step's operator. Such reversing steps are needed for deployment if the target attribute for mining has been changed.

Returns:

a collection of steps

Throws:

M4Exception

getReversedStep

Step getReversedStep()
                     throws M4Exception

Returns the step whose feature construction is reversed by this step, or null if no such step exists.

Returns:

a Step

Throws:

M4Exception

addReversingStep

void addReversingStep(Step reversingStep)
                      throws M4Exception

The given step is linked as reversing step to this one.

Parameters:

reversingStep -

Throws:

M4Exception

getResultingDataModel

java.util.Collection getResultingDataModel()
                                           throws M4Exception

Returns a collection of concepts; these concepts represent the data model that the current Case produced up to this Step.

Returns:

a collection of concepts

Throws:

M4Exception

belongsToChainOrSubChain

boolean belongsToChainOrSubChain(Chain theChain)
                                 throws M4Exception

This method returns TRUE if this Step belongs to the given Chain, or to a direct or indirect subchain of the given Chain.

Parameters:

theChain - the given Chain

Returns:

TRUE iff this Step belongs to the given Chain or one of its (direct or indirect) subchains.

Throws:

M4Exception

hasPredecessorOutsideChain

boolean hasPredecessorOutsideChain()
                                   throws M4Exception

This method returns TRUE if this Step has a direct predecessor that does not belong to the same chain, nor one of its subchains.

Returns:

TRUE if a predecessor of this Step exists outside this Step's Chain

Throws:

M4Exception

hasSuccessorOutsideChain

boolean hasSuccessorOutsideChain()
                                 throws M4Exception

This method returns TRUE if this Step has a direct successor that does not belong to the same chain, nor one of its subchains.

Returns:

TRUE if a successor of this Step exists outside this Step's Chain

Throws:

M4Exception

getParameterTuple

Parameter getParameterTuple(java.lang.String name,
                            int loopNr)
                            throws M4Exception

Return the parameter (tuple) of this step with the given name and loop number.

Parameters:

name - the Name

loopNr - the loop number as in M4

Throws:

M4Exception

getParameter

java.util.Collection getParameter(OpParam theOpParam,
                                  int loopNr)
                                  throws M4Exception

Returns the instance of the given OpParam that is currently set in this Step. The returned Collection contains instances of ParameterObjects. For single parameters, only one object is contained in the collection; for array parameters, there can be more; for optional parameters, the collection can be empty.

Parameters:

theOpParam - an OpParam object specifying the parameter to be returned

loopNr - the loop index for this parameter (ignored for non-loopable parameters)

Returns:

a Collection of ParameterObjects

Throws:

M4Exception

getSingleParameterObject

ParameterObject getSingleParameterObject(java.lang.String parameterName)

Returns the parameter object of the first parameter tuple with the given name and loop number 0. NULL may be returned.

Parameters:

parameterName - the name of the parameter whose parameter object is to be retrieved

Returns:

a ParameterObject

setParameter

java.util.Map setParameter(OpParam theOpParam,
                           java.util.Collection theParameterObjects,
                           int loopNr)
                           throws M4Exception

Sets the parameter specified by the given OpParam. Depending on the type of parameter, the given Collection can contain exactly one (for a single parameter), or several (for an array parameter), ParameterObjects.

Parameters:

theOpParam - an OpParam object specifying the parameter to be set

theParameterObjects - a Collection of ParameterObjects

loopNr - the loop index for this parameter (ignored for non-loopable parameters)

Returns:

a Map that may be null or empty; it maps output feature parameters to the previous names of their parameter objects (so the map is null or empty if the given OpParam is not for output feature parameters, or if no parameter objects existed previously)

Throws:

M4Exception

checkInputParameterEntries

boolean checkInputParameterEntries()
                                   throws M4Exception

This method checks, for the current set of values of input parameters in this step, whether they fulfill all parameter contraints. If not, an exception is thrown whose message can be used by the GUI as an error message for the user. The user can then correct the corresponding parameter entry, then this method should be called again, until it returns TRUE and does not throw an exception. The method can be called before the output is created, as it will only check the validity of the input parameter values.

Returns:

TRUE iff the current set of input parameters is valid for this step, in terms of all constraints holding for the parameters.

Throws:

M4Exception - An exception carrying a meaningful error message, intended to direct the user to improve the parameter settings.

checkOutputParameterEntries

boolean checkOutputParameterEntries()
                                    throws M4Exception

This method checks, for the current set of values of output parameters in this step, whether they fulfill all parameter contraints. If not, an exception is thrown whose message can be used by the GUI as an error message for the user. The user can then correct the corresponding parameter entry, then this method should be called again, until it returns TRUE and does not throw an exception.

Returns:

TRUE iff the current set of output parameters is valid for this step, in terms of all constraints holding for the parameters.

Throws:

M4Exception - An exception carrying a meaningful error message, intended to direct the user to improve the parameter settings.

isVisible

boolean isVisible(Feature theFeature)
                  throws M4Exception

This method returns TRUE iff the given Feature may be displayed in the input concept, or in a list of Features to choose from for a parameter. If FALSE is returned, it means that the given Feature is constructed by a FeatureConstruction operator in a different branch of the chain of steps, thus the Feature has no meaning for this step.

Parameters:

theFeature - The feature for which visibility is tested

Returns:

TRUE iff the feature can be used in this Step

Throws:

M4Exception

checkFeatureRemoval

java.lang.String checkFeatureRemoval(Concept theInputConcept,
                                     Feature theFeature)
                                     throws M4Exception

This method checks if any problems with the validity of this step would occur if the given feature were removed from the given input concept of this step. A String describing the problem is returned, or NULL if no problem would occur.

Parameters:

theInputConcept - input concept in which the feature would be deleted

nameOfFeature -

Returns:

a hypothetical error message, or NULL if no error would occur

Throws:

M4Exception

getCorrespondingOutputFeatures

java.util.Collection getCorrespondingOutputFeatures(Concept theInputConcept,
                                                    Feature theFeature)
                                                    throws M4Exception

This method finds all features in the output concept of this step that correspond to the given feature in the given input concept of this step.

Parameters:

theInputConcept -

theFeature -

Returns:

a collection of features

Throws:

M4Exception

createOutput

void createOutput(OpParam theOpParam,
                  java.util.Collection theNames)
                  throws M4Exception

This method must only be called if no output objects existed for this Step before! This method creates the output concept or output feature(s) for this step. What is to be created is specified by the given OpParam object. The name(s) for the new object(s) are given in the collection theNames. If there are both output concept AND output feature(s), please call this method FIRST with the concept!

Parameters:

theOpParam - the OpParam object specifying which output parameter is meant

theNames - a Collection of Strings giving the name(s) for the new object(s)

Throws:

M4Exception

renameOutput

void renameOutput(OpParam theOpParam,
                  java.util.Collection theNames)
                  throws M4Exception

This method changes the names of the output parameter objects; the latter are assumed to exist. If the input parameters of the step have also changed, call the method updateOutput before this one.

Parameters:

theOpParam - the OpParam object specifying which output parameter is meant

theNames - a Collection of Strings giving the new name(s)

Throws:

M4Exception

updateOutput

void updateOutput(OpParam theOpParam)
                  throws M4Exception

This method must only be called if any input parameter of this Step was changed. It ensures consistency of the output parameter objects with the input parameter objects. If the name of the output parameter has also changed, call the method renameOutput afterwards.

Parameters:

theOpParam - the OpParam object specifying which output parameter is meant

Throws:

M4Exception

propagateOutputChanges

void propagateOutputChanges()
                            throws M4Exception

This method should be called after changing some outputs of this Step. It ensures that the following (depending) steps adjust their output, too.

Throws:

M4Exception

adaptOutputToChangedInput

boolean adaptOutputToChangedInput()
                                  throws M4Exception

Ensures that the output of this step reflects the current state of the input parameters.

Returns:

TRUE iff the output has changed at all (on the conceptual level)

Throws:

M4Exception

handleOldInput

void handleOldInput()
                    throws M4Exception

To be called after changing the input of this step; ensures that old output attributes are removed from a replaced input concept.

Throws:

M4Exception

inputChangeCanAffectOutput

boolean inputChangeCanAffectOutput(OpParam theOpParam)
                                   throws M4Exception

Returns TRUE iff a change to the given input OpParam can have any effect on the output parameters of this Step. For example, if the NewRangeMin-parameter of a Scaling-Step is changed then the output parameters are not affected. In contrast, if the number of features selected in a manual FeatureSelection step changes, then the output concept must be updated.

Parameters:

theOpParam - an input OpParam of the operator of this step

Returns:

TRUE if the output may have to be updated if the input was updated

Throws:

M4Exception

getPossibleConceptsForParam

java.util.Collection getPossibleConceptsForParam(OpParam opParam)
                                                 throws M4Exception

This method returns a Collection of Concepts from which the feature denoted by the given OpParam must be selected. NULL is returned if no constraint specifies where to select the feature from. An empty collection is returned when there is such a specifying constraint, but the corresponding concept parameter has not been instantiated yet. For example, a feature given by 'TheTargetAttribute' is usually selected from 'TheInputConcept' but if the latter has not been chosen by the user yet, an empty collection is returned.

Parameters:

opParam - the OpParam parameter referring to an input feature.

Returns:

a Collection of the Concepts this feature is allowed to be selected from (due to an 'IN' constraint).

Throws:

M4Exception

getOpParamsToSelectFeatureParamObjectsFrom

java.util.Collection getOpParamsToSelectFeatureParamObjectsFrom(OpParam opParam)
                                                                throws M4Exception

Whenever an input of type BaseAttribute or MultiColumnFeature is expected the possible Concepts the Features may come from are explicitly given by constraints. These constraints refer to the parameter names as used for the OpParam objects. This method returns a Collection of such OpParam names for input Concept parameters, e.g. "TheInputConcept".

Parameters:

opParam - the OpParam parameter referring to an input feature.

Returns:

a Collection consisting of the OpParam names (Strings) of the Concepts this feature is allowed to be selected from (due to an 'IN' constraint).

Throws:

M4Exception

isAttribToTakeFromFromConcept

boolean isAttribToTakeFromFromConcept(OpParam theAttribOpParam,
                                      OpParam theRelationOpParam)
                                      throws M4Exception

Returns TRUE iff there is a constraint indicating that the feature parameter indicated by theAttribOpParam is to be taken from the FromConcept of the relation given by theRelationOpParam.

Parameters:

theAttribOpParam -

theRelationOpParam -

Returns:

Throws:

M4Exception

isAttribToTakeFromToConcept

boolean isAttribToTakeFromToConcept(OpParam theAttribOpParam,
                                    OpParam theRelationOpParam)
                                    throws M4Exception

Returns TRUE iff there is a constraint indicating that the feature parameter indicated by theAttribOpParam is to be taken from the ToConcept of the relation given by theRelationOpParam.

Parameters:

theAttribOpParam -

theRelationOpParam -

Returns:

Throws:

M4Exception

getPossibleInputConcepts

java.util.Collection getPossibleInputConcepts()
                                              throws M4Exception

This method finds all Concepts that are either of type DB or are created as an output concept by a Step that precedes this Step in the chain.

Returns:

a Collection of Concepts

Throws:

M4Exception

isContainedInInputConcept

boolean isContainedInInputConcept(OpParam outputFeature)
                                  throws M4Exception

This method must only be called for an output feature. It is checked whether the output feature is constrained to be IN the input concept.

Parameters:

outputFeature - the OpParam representing the output feature

Returns:

TRUE iff the outputFeature's name should be selected from the names of the features of the input concept; FALSE if any new name can be given to the outputFeature.

Throws:

M4Exception

removePredecessor

void removePredecessor()
                       throws M4Exception

Removes the link to the specified Predecessor.

Throws:

M4Exception

createParameterTuple

Parameter createParameterTuple(java.lang.String name,
                               ParameterObject object,
                               long number,
                               int loopNumber,
                               java.lang.String type)
                               throws M4Exception

Creates a Parameter that will be connected to this Step. The name of the Parameter must be unique for this Step.

Parameters:

name - The name for the new Parameter.

object - The parameter object. It must be a Concept, Relationship , BaseAttribute, MultiColumnFeature or Value

number - the parameter number

loopNumber - the loop number

type - the parameter type. Possible values are Parameter.TYPE_INPUT or Parameter.TYPE_OUTPUT

Returns:

The new Parameter object.

Throws:

M4Exception

createValueParameterTuple

Parameter createValueParameterTuple(java.lang.String value,
                                    java.lang.String datatype,
                                    java.lang.String name,
                                    long number,
                                    int loopNumber,
                                    java.lang.String type)
                                    throws M4Exception

Creates a Parameter and a Value that will be connected to this Step. The name of the Parameter must be unique for this Step. A Value object will be created that will be connected to the created Parameter.

Parameters:

value - The value for the Value Object.

datatype - The datatype for the value. Use one of the predefined types available for @link DomainDatatype

name - The name for the new Parameter.

number - the parameter number

loopNumber - the loop number

type - the parameter type. Possible values are Parameter.TYPE_INPUT or Parameter.TYPE_OUTPUT

Returns:

The new Parameter object.

Throws:

M4Exception