edu.umn.cs.spatialHadoop.core

Class HilbertCurvePartitioner

java.lang.Object

edu.umn.cs.spatialHadoop.core.Partitioner

edu.umn.cs.spatialHadoop.core.HilbertCurvePartitioner

public class HilbertCurvePartitioner
extends Partitioner

Author:

Ahmed Eldawy

Field Summary

Fields

Modifier and Type	Field and Description
protected Rectangle	mbr The MBR of the original input file
protected static int	Resolution
protected int[]	splits Splits along the Hilbert curve

Constructor Summary

Constructors

Constructor and Description
HilbertCurvePartitioner()

Method Summary

Methods

Modifier and Type	Method and Description
static int	computeHValue(int n, int x, int y) Compute Hilbert curve value for a point (x, y) in a square of size (n*n)
static int	computeHValue(Rectangle inMBR, double x, double y)
protected void	createFromHValues(int[] hValues, int partitions) Create a ZCurvePartitioner from a list of points
void	createFromPoints(Rectangle mbr, Point[] points, int numPartitions) Populate this partitioner for a set of points and number of partitions
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

splits

protected int[] splits

Splits along the Hilbert curve

mbr

protected Rectangle mbr

The MBR of the original input file

Resolution

protected static final int Resolution

See Also:

Constant Field Values

Constructor Detail

HilbertCurvePartitioner

public HilbertCurvePartitioner()

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

createFromHValues

protected void createFromHValues(int[] hValues,
                     int partitions)

Create a ZCurvePartitioner from a list of points

Parameters:

vsample -

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

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

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:

computeHValue

public static int computeHValue(int n,
                int x,
                int y)

Compute Hilbert curve value for a point (x, y) in a square of size (n*n)

Parameters:

n - - Size of the square

x - - x dimension (short)

y - - y dimension (short)

Returns:

computeHValue

public static int computeHValue(Rectangle inMBR,
                double x,
                double y)

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:

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:

getPartitionCount

public int getPartitionCount()

Description copied from class: Partitioner

Returns total number of partitions

Specified by:

getPartitionCount in class Partitioner

Returns:

main

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

Throws:

java.io.IOException