weka.knowledgeflow

Class Flow

java.lang.Object

weka.knowledgeflow.Flow

public class Flow
extends java.lang.Object

Class that encapsulates the Steps involved in a Knowledge Flow process.

Version:

$Revision: $

Author:

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

Field Summary

Fields

Modifier and Type	Field and Description
static java.util.List<javax.swing.filechooser.FileFilter>	FLOW_FILE_EXTENSIONS Holds available file extensions for flow files handled

Constructor Summary

Constructors

Constructor and Description
Flow()

Method Summary

Modifier and Type	Method and Description
void	addAll(java.util.List<StepManagerImpl> steps) All all steps in the supplied list to this Flow
void	addStep(StepManagerImpl manager) Add the given Step to this flow
boolean	connectSteps(StepManagerImpl source, StepManagerImpl target, java.lang.String connectionType) Connect the supplied source and target steps using the given connectionType.
boolean	connectSteps(StepManagerImpl source, StepManagerImpl target, java.lang.String connectionType, boolean force) Connect the supplied source and target steps using the given connectionType.
Flow	copyFlow() Make a copy of this Flow
java.util.List<StepManagerImpl>	findPotentialStartPoints() Get a list of potential start points in this Flow.
StepManagerImpl	findStep(java.lang.String stepName) Find a Step by name
java.lang.String	getFlowID() Get an ID string for this flow.
static FlowLoader	getFlowLoader(java.lang.String flowFileExtension, Logger log) Utility method to get a FlowLoader implementation suitable for loading a flow with the supplied file extension.
java.lang.String	getFlowName() Get the name of this Flow
java.util.List<StepManagerImpl>	getSteps() Get a list of the Steps in this Flow
boolean	initFlow(FlowExecutor executor) Initialize the flow by setting the execution environment and calling the init() method of each step
java.util.Iterator<StepManagerImpl>	iterator() Get an Iterator over the Steps in this flow
static Flow	JSONToFlow(java.lang.String flowJSON) Parse a Flow from the supplied JSON string
static Flow	JSONToFlow(java.lang.String flowJSON, boolean dontComplainAboutMissingConnections) Parse a Flow from the supplied JSON string
static Flow	loadFlow(java.io.File flowFile, Logger log) Utility method to load a flow from a file
static Flow	loadFlow(java.io.InputStream is, FlowLoader loader) Utility method to load a flow from the supplied input stream using the supplied FlowLoader
static Flow	loadFlow(java.io.Reader r, FlowLoader loader) Utility method to load a flow from the supplied reader using the supplied FlowLoader
void	removeStep(StepManagerImpl manager) Remove the supplied Step from this flow
void	renameStep(StepManagerImpl step, java.lang.String newName) Rename the supplied step with the supplied name
void	renameStep(java.lang.String oldName, java.lang.String newName) Rename a Step.
void	saveFlow(java.io.File file) Save this Flow to the supplied File
void	setFlowName(java.lang.String name) Set the name of this Flow
int	size() Get the number of steps in this flow
java.lang.String	toJSON() Return the JSON encoded version of this Flow

Methods inherited from class java.lang.Object

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

Field Detail

FLOW_FILE_EXTENSIONS

public static final java.util.List<javax.swing.filechooser.FileFilter> FLOW_FILE_EXTENSIONS

Holds available file extensions for flow files handled

Constructor Detail

Flow

public Flow()

Method Detail

getFlowLoader

public static FlowLoader getFlowLoader(java.lang.String flowFileExtension,
                                       Logger log)
                                throws WekaException

Utility method to get a FlowLoader implementation suitable for loading a flow with the supplied file extension.

Parameters:

flowFileExtension - the file extension to get a FlowLoader for

log - the log in use

Returns:

a FlowLoader

Throws:

WekaException - if a problem occurs

loadFlow

public static Flow loadFlow(java.io.File flowFile,
                            Logger log)
                     throws WekaException

Utility method to load a flow from a file

Parameters:

flowFile - the file to load from

log - the log to use

Returns:

the loaded Flow

Throws:

WekaException - if a problem occurs

loadFlow

public static Flow loadFlow(java.io.InputStream is,
                            FlowLoader loader)
                     throws WekaException

Utility method to load a flow from the supplied input stream using the supplied FlowLoader

Parameters:

is - the input stream to load from

loader - the FlowLoader to use

Returns:

the loaded Flow

Throws:

WekaException - if a problem occurs

loadFlow

public static Flow loadFlow(java.io.Reader r,
                            FlowLoader loader)
                     throws WekaException

Utility method to load a flow from the supplied reader using the supplied FlowLoader

Parameters:

r - the reader to load from

loader - the FlowLoader to use

Returns:

the loaded flow

Throws:

WekaException - if a problem occurs

JSONToFlow

public static Flow JSONToFlow(java.lang.String flowJSON)
                       throws WekaException

Parse a Flow from the supplied JSON string

Parameters:

flowJSON - the JSON string to parse

Returns:

the Flow

Throws:

WekaException - if a problem occurs

JSONToFlow

public static Flow JSONToFlow(java.lang.String flowJSON,
                              boolean dontComplainAboutMissingConnections)
                       throws WekaException

Parse a Flow from the supplied JSON string

Parameters:

flowJSON - the JSON string to parse

dontComplainAboutMissingConnections - true to not raise an exception if there are connections to non-existent Steps in the JSON flow

Returns:

the Flow

Throws:

WekaException - if a problem occurs

saveFlow

public void saveFlow(java.io.File file)
              throws WekaException

Save this Flow to the supplied File

Parameters:

file - the File to save to

Throws:

WekaException - if a problem occurs

getFlowName

public java.lang.String getFlowName()

Get the name of this Flow

Returns:

the name of this flow

setFlowName

public void setFlowName(java.lang.String name)

Set the name of this Flow

Parameters:

name - the name to set

getFlowID

public java.lang.String getFlowID()

Get an ID string for this flow. The ID is made up of the FlowName + "_" + the hashcode generated from the JSON representation of the flow.

Returns:

addAll

public void addAll(java.util.List<StepManagerImpl> steps)

All all steps in the supplied list to this Flow

Parameters:

steps - a list of StepManagers for the steps to add

addStep

public void addStep(StepManagerImpl manager)

Add the given Step to this flow

Parameters:

manager - the StepManager containing the Step to add

connectSteps

public boolean connectSteps(StepManagerImpl source,
                            StepManagerImpl target,
                            java.lang.String connectionType)

Connect the supplied source and target steps using the given connectionType. The connection will be successful only if both source and target are actually part of this Flow, and the target is able to accept the connection at this time.

Parameters:

source - the StepManager for the source step

target - the StepManager for the target step

connectionType - the connection type to use says it can accept the connection type at this time)

Returns:

true if the connection was successful

connectSteps

public boolean connectSteps(StepManagerImpl source,
                            StepManagerImpl target,
                            java.lang.String connectionType,
                            boolean force)

Connect the supplied source and target steps using the given connectionType. The connection will be successful only if both source and target are actually part of this Flow, and the target is able to accept the connection at this time.

Parameters:

source - the StepManager for the source step

target - the StepManager for the target step

connectionType - the connection type to use

force - true to force the connection (i.e. even if the target step says it can accept the connection type at this time)

Returns:

true if the connection was successful

renameStep

public void renameStep(StepManagerImpl step,
                       java.lang.String newName)
                throws WekaException

Rename the supplied step with the supplied name

Parameters:

step - the StepManager of the Step to rename

newName - the new name to give the step

Throws:

WekaException - if the Step is not part of this Flow.

renameStep

public void renameStep(java.lang.String oldName,
                       java.lang.String newName)
                throws WekaException

Rename a Step.

Parameters:

oldName - the name of the Step to rename

newName - the new name to use

Throws:

WekaException - if the named Step is not part of this flow

removeStep

public void removeStep(StepManagerImpl manager)
                throws WekaException

Remove the supplied Step from this flow

Parameters:

manager - the StepManager of the Step to remove

Throws:

WekaException - if the step is not part of this flow

getSteps

public java.util.List<StepManagerImpl> getSteps()

Get a list of the Steps in this Flow

Returns:

a list of StepManagers of the steps in this flow

iterator

public java.util.Iterator<StepManagerImpl> iterator()

Get an Iterator over the Steps in this flow

Returns:

an Iterator over the StepManagers of the Steps in this flow

size

public int size()

Get the number of steps in this flow

Returns:

the number of steps in this flow

findStep

public StepManagerImpl findStep(java.lang.String stepName)

Find a Step by name

Parameters:

stepName - the name of the Step to find

Returns:

the StepManager of the named Step, or null if the Step is not part of this flow

findPotentialStartPoints

public java.util.List<StepManagerImpl> findPotentialStartPoints()

Get a list of potential start points in this Flow. Potential start points are those steps that have no incoming connections.

Returns:

a list of potential start points

initFlow

public boolean initFlow(FlowExecutor executor)
                 throws WekaException

Initialize the flow by setting the execution environment and calling the init() method of each step

Parameters:

executor - the flow executor being used to execute the flow

Returns:

false if initialization failed

Throws:

WekaException - if a problem occurs during flow initialization

toJSON

public java.lang.String toJSON()
                        throws WekaException

Return the JSON encoded version of this Flow

Returns:

the flow in JSON format

Throws:

WekaException - if a problem occurs

copyFlow

public Flow copyFlow()
              throws WekaException

Make a copy of this Flow

Returns:

a copy of this Flow

Throws:

WekaException - if a problem occurs