edu.umn.cs.spatialHadoop.nasa

Class AggregateQuadTree

java.lang.Object

edu.umn.cs.spatialHadoop.nasa.AggregateQuadTree

public class AggregateQuadTree
extends java.lang.Object

Stores a quad tree of values collected from HDF files from MODIS archive.

Author:

Ahmed Eldawy

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	AggregateQuadTree.Node

Constructor Summary

Constructors

Constructor and Description
AggregateQuadTree()

Method Summary

Methods

Modifier and Type	Method and Description
static AggregateQuadTree.Node	aggregateQuery(FileSystem fs, Path p, java.awt.Rectangle query_mbr)
static AggregateQuadTree.Node	aggregateQuery(FSDataInputStream in, java.awt.Rectangle query_mbr) Perform a selection query that retrieves all points in the given range.
static void	build(Configuration conf, Path inFile, java.lang.String datasetName, Path outFile) Constructs an aggregate quad tree for an input HDF file on a selected dataset identified by its name in the file.
static void	build(short[] values, short fillValue, java.io.DataOutputStream out) Constructs an aggregate quad tree out of a two-dimensional array of values.
static int	computeZOrder(short x, short y) Computes the Z-order (Morton order) of a two-dimensional point.
static void	main(java.lang.String[] args)
static void	merge(Configuration conf, Path[] inFiles, Path outFile) Merges a list of aggregate trees (in the same order) and writes an output tree that combines all input trees.
static void	merge(java.io.DataInputStream[] inTrees, java.io.DataOutputStream outTree) Merges multiple trees of the same spatial resolution into one tree of lower temporal resolution (larger time) and the same spatial resolution.
static int	selectionQuery(FSDataInputStream in, java.awt.Rectangle query_mbr, ResultCollector2<java.awt.Point,java.lang.Short> output) Perform a selection query that retrieves all points in the given range.

Methods inherited from class java.lang.Object

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

Constructor Detail

AggregateQuadTree

public AggregateQuadTree()

Method Detail

build

public static void build(Configuration conf,
         Path inFile,
         java.lang.String datasetName,
         Path outFile)
                  throws java.lang.Exception

Constructs an aggregate quad tree for an input HDF file on a selected dataset identified by its name in the file.

Parameters:

inFile -

datasetIndex -

outFile -

Throws:

java.lang.Exception

build

public static void build(short[] values,
         short fillValue,
         java.io.DataOutputStream out)
                  throws java.io.IOException

Constructs an aggregate quad tree out of a two-dimensional array of values.

Parameters:

values -

out - - the output stream to write the constructed quad tree to

Throws:

java.io.IOException

merge

public static void merge(Configuration conf,
         Path[] inFiles,
         Path outFile)
                  throws java.io.IOException

Merges a list of aggregate trees (in the same order) and writes an output tree that combines all input trees. Input trees must have been built using on of the build(Configuration, Path, java.lang.String, Path) methods. The merged tree can be further merged using this method.

Parameters:

conf -

inFiles -

outFile -

Throws:

java.io.IOException

merge

public static void merge(java.io.DataInputStream[] inTrees,
         java.io.DataOutputStream outTree)
                  throws java.io.IOException

Merges multiple trees of the same spatial resolution into one tree of lower temporal resolution (larger time) and the same spatial resolution.

Parameters:

inTrees -

outTree -

Throws:

java.io.IOException

selectionQuery

public static int selectionQuery(FSDataInputStream in,
                 java.awt.Rectangle query_mbr,
                 ResultCollector2<java.awt.Point,java.lang.Short> output)
                          throws java.io.IOException

Perform a selection query that retrieves all points in the given range. The range is specified in the two-dimensional array positions.

Parameters:

in -

r -

Returns:

number of matched records

Throws:

java.io.IOException

aggregateQuery

public static AggregateQuadTree.Node aggregateQuery(FileSystem fs,
                                    Path p,
                                    java.awt.Rectangle query_mbr)
                                             throws java.io.IOException

Throws:

java.io.IOException

aggregateQuery

public static AggregateQuadTree.Node aggregateQuery(FSDataInputStream in,
                                    java.awt.Rectangle query_mbr)
                                             throws java.io.IOException

Perform a selection query that retrieves all points in the given range. The range is specified in the two-dimensional array positions.

Parameters:

in -

r -

Returns:

number of matched records

Throws:

java.io.IOException

computeZOrder

public static int computeZOrder(short x,
                short y)

Computes the Z-order (Morton order) of a two-dimensional point.

Parameters:

x -

y -

Returns:

main

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

Throws:

java.lang.Exception