edu.umn.cs.spatialHadoop.core

Class OGCESRIShape

java.lang.Object

edu.umn.cs.spatialHadoop.core.OGCESRIShape

All Implemented Interfaces:

Shape, TextSerializable, java.lang.Cloneable

public class OGCESRIShape
extends java.lang.Object
implements Shape

A shape class that represents an OGC compliant geometry. The geometry is enclosed inside the class and all calls are delegated to it. The class also holds extra information for each records that could represent other columns for each records. The text representation is assumed to be some kind of CSV. The shape is always the first column in that CSV. The text representation of the shape could be either a WTK (Well Known Text) or a binary representation. The WKT can be generated with PostGIS using the function ST_AsText(geom). An example may look like this:
POLYGON ((-89 43,-89 50,-97 50,-97 43,-89 43)) The binary representation can be generated from PostGIS by selecting the geom column using a normal select statement. When a shape is parsed, we detect the format and use the appropriate parser. When writing to text, we always use the binary representation as it is faster and more compact. For binary serialization/deserialization, we use the PostGIS writer and parser.

Author:

Ahmed Eldawy

Field Summary

Fields

Modifier and Type	Field and Description
OGCGeometry	geom The underlying geometry

Constructor Summary

Constructors

Constructor and Description
OGCESRIShape()
OGCESRIShape(OGCGeometry geom)

Method Summary

Methods

Modifier and Type	Method and Description
Shape	clone() Returns a clone of this shape
double	distanceTo(double x, double y) Gets the distance of this shape to the given point.
void	draw(java.awt.Graphics g, double xscale, double yscale) Draws the shape to the given graphics and scale.
void	draw(java.awt.Graphics g, Rectangle fileMBR, int imageWidth, int imageHeight, double scale) Draws a shape to the given graphics.
void	drawESRIGeom(java.awt.Graphics g, OGCGeometry geom, double xscale, double yscale)
void	fromText(Text text) Retrieve information from the given text.
Rectangle	getMBR() Returns minimum bounding rectangle for this shape.
static byte[]	hexToBytes(java.lang.String hex) Convert a string containing a hex string to a byte array of binary.
boolean	isIntersected(Shape s) Returns true if this shape is intersected with the given shape
void	readFields(java.io.DataInput in)
java.lang.String	toString()
Text	toText(Text text) Store current object as string in the given text appending text already there.
void	write(java.io.DataOutput out)

Methods inherited from class java.lang.Object

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

Field Detail

geom

public OGCGeometry geom

The underlying geometry

Constructor Detail

OGCESRIShape

public OGCESRIShape()

OGCESRIShape

public OGCESRIShape(OGCGeometry geom)

Method Detail

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

hexToBytes

public static byte[] hexToBytes(java.lang.String hex)

Convert a string containing a hex string to a byte array of binary. For example, the string "AABB" is converted to the byte array {0xAA, 0XBB}

Parameters:

hex -

Returns:

toText

public Text toText(Text text)

Description copied from interface: TextSerializable

Store current object as string in the given text appending text already there.

Specified by:

toText in interface TextSerializable

fromText

public void fromText(Text text)

Description copied from interface: TextSerializable

Retrieve information from the given text.

Specified by:

fromText in interface TextSerializable

getMBR

public Rectangle getMBR()

Description copied from interface: Shape

Returns minimum bounding rectangle for this shape.

Specified by:

getMBR in interface Shape

Returns:

distanceTo

public double distanceTo(double x,
                double y)

Description copied from interface: Shape

Gets the distance of this shape to the given point.

Specified by:

distanceTo in interface Shape

Returns:

isIntersected

public boolean isIntersected(Shape s)

Description copied from interface: Shape

Returns true if this shape is intersected with the given shape

Specified by:

isIntersected in interface Shape

Returns:

clone

public Shape clone()

Description copied from interface: Shape

Returns a clone of this shape

Specified by:

clone in interface Shape

Overrides:

clone in class java.lang.Object

Returns:

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

draw

public void draw(java.awt.Graphics g,
        Rectangle fileMBR,
        int imageWidth,
        int imageHeight,
        double scale)

Description copied from interface: Shape

Draws a shape to the given graphics.

Specified by:

draw in interface Shape

Parameters:

g - - the graphics or canvas to draw to

fileMBR - - the MBR of the file in which the shape is contained

imageWidth - - width of the image to draw

imageHeight - - height of the image to draw

scale - - the scale used to convert shape coordinates to image coordinates

draw

public void draw(java.awt.Graphics g,
        double xscale,
        double yscale)

Description copied from interface: Shape

Draws the shape to the given graphics and scale.

Specified by:

draw in interface Shape

Parameters:

g - - the graphics to draw the shape to.

xscale - - scale of the image x-axis in terms of pixels per points.

yscale - - scale of the image y-axis in terms of pixels per points.

drawESRIGeom

public void drawESRIGeom(java.awt.Graphics g,
                OGCGeometry geom,
                double xscale,
                double yscale)