ca.uqac.lif.labpal.provenance

Class DataTracker

java.lang.Object

ca.uqac.lif.labpal.provenance.DataTracker

public class DataTracker
extends java.lang.Object

Tracks the ownership of each data point produced by a lab. This is the class taking care of the LabPal Datapoint Identifiers (LDI).

Author:

Sylvain Hallé

Field Summary

Fields

Modifier and Type	Field and Description
protected ca.uqac.lif.petitpoucet.OwnershipManager	m_lab The lab
protected static int	s_maxDepth The maximum depth of a provenance tree

Constructor Summary

Constructors

Constructor and Description
DataTracker(ca.uqac.lif.petitpoucet.OwnershipManager lab) Creates a new data tracker

Method Summary

Modifier and Type	Method and Description
ca.uqac.lif.petitpoucet.ProvenanceNode	explain(ca.uqac.lif.petitpoucet.NodeFunction nf) Builds a provenance tree for a given data point
protected ca.uqac.lif.petitpoucet.ProvenanceNode	explain(ca.uqac.lif.petitpoucet.NodeFunction nf, java.util.Set<ca.uqac.lif.petitpoucet.NodeFunction> seen_functions, int depth) Builds a provenance tree for a given data point
ca.uqac.lif.petitpoucet.ProvenanceNode	explain(java.lang.String datapoint_id) Produces a provenance tree for a given LDI
ca.uqac.lif.petitpoucet.NodeFunction	getNodeFunction(java.lang.String datapoint_id)
java.lang.Object	getOwner(java.lang.String id) Gets the owner of a data point

Methods inherited from class java.lang.Object

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

Field Detail

m_lab

protected ca.uqac.lif.petitpoucet.OwnershipManager m_lab

The lab

s_maxDepth

protected static final transient int s_maxDepth

The maximum depth of a provenance tree

See Also:

Constant Field Values

Constructor Detail

DataTracker

public DataTracker(ca.uqac.lif.petitpoucet.OwnershipManager lab)

Creates a new data tracker

Parameters:

lab - The lab this tracker is associated with

Method Detail

getOwner

public java.lang.Object getOwner(java.lang.String id)

Gets the owner of a data point

Parameters:

id - The data point ID

Returns:

The owner; maybe null if no owner can be found

getNodeFunction

public ca.uqac.lif.petitpoucet.NodeFunction getNodeFunction(java.lang.String datapoint_id)

explain

public ca.uqac.lif.petitpoucet.ProvenanceNode explain(java.lang.String datapoint_id)

Produces a provenance tree for a given LDI

Parameters:

datapoint_id - The LDI

Returns:

A reference to the root of the provenance tree

explain

public ca.uqac.lif.petitpoucet.ProvenanceNode explain(ca.uqac.lif.petitpoucet.NodeFunction nf)

Builds a provenance tree for a given data point

Parameters:

nf - A node function

Returns:

The root of the provenance tree

explain

protected ca.uqac.lif.petitpoucet.ProvenanceNode explain(ca.uqac.lif.petitpoucet.NodeFunction nf,
                                                         java.util.Set<ca.uqac.lif.petitpoucet.NodeFunction> seen_functions,
                                                         int depth)

Builds a provenance tree for a given data point

Parameters:

nf - The ID of the current node

seen_functions - A set of nodes functions already included in the tree. This is to avoid infinite looping due to possible circular dependencies.

depth - A counter that is being decreased every time the method is called recursively. This can be used to specify the maximum depth of the provenance tree.

Returns:

The root of the provenance tree