ilConditionalNode Class Reference

PhpIncludeInspection More...

Inheritance diagram for ilConditionalNode:

Collaboration diagram for ilConditionalNode:

Public Member Functions
	__construct (ilWorkflow $a_context)
	Default constructor. More...
	activate ()
	Activates the node. More...
	deactivate ()
	Deactivates the node. More...
	checkTransitionPreconditions ()
	Checks, if the preconditions of the node to transit are met. More...
	attemptTransition ()
	Attempts to transit the node. More...
	executeTransition ()
	Executes the 'then'-transition of the node. More...
	executeElseTransition ()
	Executes the 'else'-transition of the node. More...
	addEmitter (ilEmitter $emitter, $else_emitter=false)
	Adds an emitter to one of the lists attached to the node. More...
	addActivity (ilActivity $activity, $else_activity=false)
	Adds an activity to one of the lists attached to the node. More...
	setEvaluationExpression ($a_expression)
	notifyDetectorSatisfaction (ilDetector $detector)
	This method is called by detectors, that just switched to being satisfied. More...
	getActivities ($else=false)
	Returns all currently set activites. More...
	getEmitters ($else=false)
	Returns all currently set emitters. More...
Public Member Functions inherited from ilBaseNode
	addDetector (ilDetector $detector)
	Adds a detector to the list of detectors. More...
	getDetectors ()
	Returns all currently set detectors. More...
	addEmitter (ilEmitter $emitter)
	Adds an emitter to the list of emitters. More...
	getEmitters ()
	Returns all currently set emitters. More...
	addActivity (ilActivity $activity)
	Adds an activity to the list of activities. More...
	getActivities ()
	Returns all currently set activities. More...
	getContext ()
	Returns a reference to the parent workflow object. More...
	setName ($name)
	getName ()
	getRuntimeVars ()
	setRuntimeVars ($runtime_vars)
	getRuntimeVar ($name)
	setRuntimeVar ($name, $value)
	onActivate ()
	Method called on activation of the node. More...
	onDeactivate ()
	Method calles on deactivation of the node. More...
	isActive ()
	Returns the activation status of the node. More...
	attemptTransition ()
	checkTransitionPreconditions ()
	executeTransition ()
	activate ()
	deactivate ()
	notifyDetectorSatisfaction (ilDetector $detector)

Private Member Functions
	executeActivities ()
	Executes all 'then'-activities attached to the node. More...
	executeElseActivities ()
	Exectes all 'else'-activities attached to the node. More...
	executeEmitters ()
	Executes all 'then'-emitters attached to the node. More...
	executeElseEmitters ()
	Executes all 'else'-emitters attached to the node. More...

Private Attributes
	$else_emitters
	$else_activities
	$evaluation_expression = "return true;"

Additional Inherited Members
Protected Attributes inherited from ilBaseNode
	$context
	$detectors
	$emitters
	$activities
	$active = false
	$name
	$runtime_vars

Detailed Description

PhpIncludeInspection

Conditional node of the petri net based workflow engine.

The conditional node is a deciding node. It features a doubled set of emitters and activities. The new set is prefixed with 'else_'. In the core of it, a given piece of php code is executed that returns either true, false or null, telling the node which set is to be executed - if any. This takes advantage of create_function, which is just as evil as eval. Because of that, the configuration of the conditional node must not be made available to users/admins and the content which makes up the evaluation method has no business in the database as this may pose a severe risk. Put these code pieces into the workflow object and set it during workflow creation. Remember: I told you before. Alternatively, you can extend this class and pre-set a code, that takes parameters from ilSetting, ini-Files, water diviner... up to you. Keep in mind to check these parameters for type and where possible, avoid strings and/or types that allow larger code segments.

Author

Maximilian Becker mbeck.nosp@m.er@d.nosp@m.ataba.nosp@m.y.de

Version

$Id$

/

Definition at line 29 of file class.ilConditionalNode.php.

Constructor & Destructor Documentation

__construct()

ilConditionalNode::__construct

(

ilWorkflow

$a_context

)

Default constructor.

Parameters

ilWorkflow

Reference to the parent workflow.

Definition at line 60 of file class.ilConditionalNode.php.

References array.

    {
        $this->context = $a_context;
        $this->detectors = array();
        $this->emitters = array();
        $this->else_emitters = array();
        $this->activities = array();
        $this->else_activities = array();
    }

Member Function Documentation

activate()

ilConditionalNode::activate

(

)

Activates the node.

Implements ilNode.

Definition at line 73 of file class.ilConditionalNode.php.

References attemptTransition(), and ilBaseNode\onActivate().

    {
        $this->active = true;
        foreach ($this->detectors as $detector) {
            $detector->onActivate();
        }
        $this->onActivate();
        $this->attemptTransition();
    }

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addActivity()

ilConditionalNode::addActivity	(	ilActivity	$activity,
			$else_activity = false
	)

Adds an activity to one of the lists attached to the node.

Parameters

ilActivity	$activity
boolean	$else_activity	True, if the activity should be an 'else'-activity.

Definition at line 237 of file class.ilConditionalNode.php.

    {
        if (!$else_activity) {
            $this->activities[] = $activity;
        } else {
            $this->else_activities[] = $activity;
        }
    }

addEmitter()

ilConditionalNode::addEmitter	(	ilEmitter	$emitter,
			$else_emitter = false
	)

Adds an emitter to one of the lists attached to the node.

Parameters

ilEmitter	$emitter
boolean	$else_emitter	True, if the emitter should be an 'else'-emitter.

Definition at line 222 of file class.ilConditionalNode.php.

    {
        if (!$else_emitter) {
            $this->emitters[] = $emitter;
        } else {
            $this->else_emitters[] = $emitter;
        }
    }

attemptTransition()

ilConditionalNode::attemptTransition

(

)

Attempts to transit the node.

Basically, this checks for preconditions and transits, returning true or false if preconditions are not met, aka detectors are not fully satisfied.

Returns

boolean True, if transition succeeded.

Implements ilNode.

Definition at line 129 of file class.ilConditionalNode.php.

References ilBaseNode\$detectors, executeElseTransition(), and executeTransition().

Referenced by activate(), and notifyDetectorSatisfaction().

    {
        $eval_function = function ($detectors) {
            return eval($this->evaluation_expression);
        };

        if ($eval_function($this->detectors) === null) {
            return false;
        }

        if ($eval_function($this->detectors) === true) {
            $this->executeTransition();
            return true;
        } else {
            $this->executeElseTransition();
            return true;
        }
    }

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checkTransitionPreconditions()

ilConditionalNode::checkTransitionPreconditions

(

)

Checks, if the preconditions of the node to transit are met.

Please note, that in a conditional node, this means the node can transit to one or another outcome. This method only returns false, if the return value of the method is neither true nor false.

Returns

boolean True, if node is ready to transit.

Implements ilNode.

Definition at line 104 of file class.ilConditionalNode.php.

References ilBaseNode\$detectors.

    {
        $eval_function = function ($detectors) {
            return eval($this->evaluation_expression);
        };

        if ($eval_function($this->detectors) === null) {
            return false;
        }

        if ($eval_function($this->detectors) === true) {
            return true;
        } else {
            return true;
        }
    }

deactivate()

ilConditionalNode::deactivate

(

)

Deactivates the node.

Implements ilNode.

Definition at line 86 of file class.ilConditionalNode.php.

References ilBaseNode\onDeactivate().

Referenced by executeElseTransition(), and executeTransition().

    {
        $this->active = false;
        foreach ($this->detectors as $detector) {
            $detector->onDeactivate();
        }
        $this->onDeactivate();
    }

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executeActivities()

ilConditionalNode::executeActivities ( )

private

Executes all 'then'-activities attached to the node.

Definition at line 151 of file class.ilConditionalNode.php.

Referenced by executeTransition().

    {
        if (count($this->activities) != 0) {
            foreach ($this->activities as $activity) {
                $activity->execute();
            }
        }
    }

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executeElseActivities()

ilConditionalNode::executeElseActivities ( )

private

Exectes all 'else'-activities attached to the node.

Definition at line 163 of file class.ilConditionalNode.php.

Referenced by executeElseTransition().

    {
        if (count($this->else_activities) != 0) {
            foreach ($this->else_activities as $activity) {
                $activity->execute();
            }
        }
    }

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executeElseEmitters()

ilConditionalNode::executeElseEmitters ( )

private

Executes all 'else'-emitters attached to the node.

Definition at line 187 of file class.ilConditionalNode.php.

Referenced by executeElseTransition().

    {
        if (count($this->else_emitters) != 0) {
            foreach ($this->else_emitters as $emitter) {
                $emitter->emit();
            }
        }
    }

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executeElseTransition()

ilConditionalNode::executeElseTransition

(

)

Executes the 'else'-transition of the node.

Definition at line 209 of file class.ilConditionalNode.php.

References deactivate(), executeElseActivities(), and executeElseEmitters().

Referenced by attemptTransition().

    {
        $this->deactivate();
        $this->executeElseActivities();
        $this->executeElseEmitters();
    }

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executeEmitters()

ilConditionalNode::executeEmitters ( )

private

Executes all 'then'-emitters attached to the node.

Definition at line 175 of file class.ilConditionalNode.php.

Referenced by executeTransition().

    {
        if (count($this->emitters) != 0) {
            foreach ($this->emitters as $emitter) {
                $emitter->emit();
            }
        }
    }

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executeTransition()

ilConditionalNode::executeTransition

(

)

Executes the 'then'-transition of the node.

Implements ilNode.

Definition at line 199 of file class.ilConditionalNode.php.

References deactivate(), executeActivities(), and executeEmitters().

Referenced by attemptTransition().

    {
        $this->deactivate();
        $this->executeActivities();
        $this->executeEmitters();
    }

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getActivities()

ilConditionalNode::getActivities

(

$else = false

)

Returns all currently set activites.

Parameters

boolean

$else

True, if else activities should be returned.

Returns

Array Array with objects of ilActivity

Definition at line 308 of file class.ilConditionalNode.php.

References ilBaseNode\$activities, and $else_activities.

    {
        if ($else) {
            return $this->else_activities;
        }

        return $this->activities;
    }

getEmitters()

ilConditionalNode::getEmitters

(

$else = false

)

Returns all currently set emitters.

Parameters

boolean

$else

True, if else emitters should be returned.

Returns

Array Array with objects of ilEmitter

Definition at line 324 of file class.ilConditionalNode.php.

References $else_emitters, and ilBaseNode\$emitters.

    {
        if ($else) {
            return $this->else_emitters;
        }

        return $this->emitters;
    }

notifyDetectorSatisfaction()

ilConditionalNode::notifyDetectorSatisfaction

(

ilDetector

$detector

)

This method is called by detectors, that just switched to being satisfied.

Parameters

ilDetector

$detector

ilDetector which is now satisfied.

Returns

mixed|void

Implements ilNode.

Definition at line 294 of file class.ilConditionalNode.php.

References attemptTransition(), and ilBaseNode\isActive().

    {
        if ($this->isActive()) {
            $this->attemptTransition();
        }
    }

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setEvaluationExpression()

ilConditionalNode::setEvaluationExpression

(

$a_expression

)

Definition at line 282 of file class.ilConditionalNode.php.

    {
        $this->evaluation_expression = $a_expression;
    }

Field Documentation

$else_activities

ilConditionalNode::$else_activities

private

Definition at line 45 of file class.ilConditionalNode.php.

Referenced by getActivities().

$else_emitters

ilConditionalNode::$else_emitters

private

Definition at line 37 of file class.ilConditionalNode.php.

Referenced by getEmitters().

$evaluation_expression

ilConditionalNode::$evaluation_expression = "return true;"

private

Definition at line 53 of file class.ilConditionalNode.php.

---

The documentation for this class was generated from the following file:

• Services/WorkflowEngine/classes/nodes/class.ilConditionalNode.php