edu.umn.cs.spatialHadoop.core

Class QuadTreePartitioner

java.lang.Object

edu.umn.cs.spatialHadoop.core.Partitioner

edu.umn.cs.spatialHadoop.core.QuadTreePartitioner

public class QuadTreePartitioner
extends Partitioner

Partition the space based on a Quad tree

Author:

Ahmed Eldawy

Field Summary

Fields

Modifier and Type	Field and Description
protected int[]	leafNodeIDs ID of all leaf nodes in partition tree
protected Rectangle	mbr The minimal bounding rectangle of the underlying file

Constructor Summary

Constructors

Constructor and Description
QuadTreePartitioner() A default constructor to be able to dynamically instantiate it and deserialize it

Method Summary

Methods

Modifier and Type	Method and Description
void	createFromPoints(Rectangle mbr, Point[] points, int numPartitions) Populate this partitioner for a set of points and number of partitions
protected void	createFromZValues(long[] zValues, int partitions) Create a ZCurvePartitioner from a list of points
CellInfo	getPartition(int partitionID) Returns the details of a specific partition given its ID.
CellInfo	getPartitionAt(int index) Returns the detail of a partition given its position starting from zero and ending at partitionCount() - 1
int	getPartitionCount() Returns total number of partitions
static void	main(java.lang.String[] args)
int	overlapPartition(Shape shape) Returns only one overlapping partition.
void	overlapPartitions(Shape shape, ResultCollector<java.lang.Integer> matcher) Overlap a shape with partitions and calls a matcher for each overlapping partition.
void	readFields(java.io.DataInput in)
void	write(java.io.DataOutput out)

Methods inherited from class edu.umn.cs.spatialHadoop.core.Partitioner

getPartitioner, setPartitioner

Methods inherited from class java.lang.Object

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

Field Detail

mbr

protected Rectangle mbr

The minimal bounding rectangle of the underlying file

leafNodeIDs

protected int[] leafNodeIDs

ID of all leaf nodes in partition tree

Constructor Detail

QuadTreePartitioner

public QuadTreePartitioner()

A default constructor to be able to dynamically instantiate it and deserialize it

Method Detail

createFromPoints

public void createFromPoints(Rectangle mbr,
                    Point[] points,
                    int numPartitions)

Description copied from class: Partitioner

Populate this partitioner for a set of points and number of partitions

Specified by:

createFromPoints in class Partitioner

createFromZValues

protected void createFromZValues(long[] zValues,
                     int partitions)

Create a ZCurvePartitioner from a list of points

Parameters:

vsample -

inMBR -

partitions -

write

public void write(java.io.DataOutput out)
           throws java.io.IOException

Throws:

java.io.IOException

readFields

public void readFields(java.io.DataInput in)
                throws java.io.IOException

Throws:

java.io.IOException

overlapPartition

public int overlapPartition(Shape shape)

Description copied from class: Partitioner

Returns only one overlapping partition. If the given shape overlaps more than one partitions, the partitioner returns only one of them according to its own criteria. If it does not overlap any partition, it returns -1 which is an invalid partition ID.

Specified by:

overlapPartition in class Partitioner

Returns:

overlapPartitions

public void overlapPartitions(Shape shape,
                     ResultCollector<java.lang.Integer> matcher)

Description copied from class: Partitioner

Overlap a shape with partitions and calls a matcher for each overlapping partition.

Specified by:

overlapPartitions in class Partitioner

getPartitionCount

public int getPartitionCount()

Description copied from class: Partitioner

Returns total number of partitions

Specified by:

getPartitionCount in class Partitioner

Returns:

getPartitionAt

public CellInfo getPartitionAt(int index)

Description copied from class: Partitioner

Returns the detail of a partition given its position starting from zero and ending at partitionCount() - 1

Specified by:

getPartitionAt in class Partitioner

Returns:

getPartition

public CellInfo getPartition(int partitionID)

Description copied from class: Partitioner

Returns the details of a specific partition given its ID.

Specified by:

getPartition in class Partitioner

Returns:

main

public static void main(java.lang.String[] args)
                 throws java.io.IOException

Throws:

java.io.IOException