edu.umn.cs.spatialHadoop.core

Class GridPartitioner

java.lang.Object

edu.umn.cs.spatialHadoop.core.Partitioner

edu.umn.cs.spatialHadoop.core.GridPartitioner

public class GridPartitioner
extends Partitioner

A partitioner that partitioner data using a uniform grid. If a shape overlaps multiple grids, it replicates it to all overlapping partitions.

Author:

Ahmed Eldawy

Constructor Summary

Constructors

Constructor and Description
GridPartitioner() A default constructor to be able to dynamically instantiate it and deserialize it
GridPartitioner(Path[] inFiles, JobConf job) Initializes a grid partitioner for a given file
GridPartitioner(Path[] inFiles, JobConf job, int width, int height)

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
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
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

Constructor Detail

GridPartitioner

public GridPartitioner()

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

GridPartitioner

public GridPartitioner(Path[] inFiles,
               JobConf job)

Initializes a grid partitioner for a given file

Parameters:

inFile -

params -

GridPartitioner

public GridPartitioner(Path[] inFiles,
               JobConf job,
               int width,
               int height)

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

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

getPartitionCount

public int getPartitionCount()

Description copied from class: Partitioner

Returns total number of partitions

Specified by:

getPartitionCount 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

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:

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: