org.gicentre.geomap.io

Class ShapefileReader

java.lang.Object

org.gicentre.geomap.io.ShapefileReader

public class ShapefileReader
extends java.lang.Object

Readers an ESRI shapefile and populates a GeoMap object with its features and attributes. A shapefile should consist of 3 separate files - name.shp containing the geometry; name.shx containing the file offsets for the components that make up the geometry; and name.dbf containing the attributes.

Version:

3.2, 4th March, 2017.

Author:

Jo Wood, giCentre, City University of London.

Constructor Summary

Constructors

Constructor and Description
ShapefileReader(processing.core.PApplet parent) Creates a shapefile reader that will scale any geographic data read to be within the given bounds.

Method Summary

Modifier and Type	Method and Description
AttributeTable	getAttributes() Deprecated. Use getAttributeTable instead that uses Processing's own Table class to store attributes.
processing.data.Table	getAttributeTable() Provides the attribute table that has been extracted from the shapefile.
java.util.Map<java.lang.Integer,Feature>	getFeatures() Provides the features that have been extracted from the shapefile.
float	getMaxX() Reports the maximum geographic value in the x-direction.
float	getMaxY() Reports the maximum geographic value in the y-direction.
float	getMinX() Reports the minimum geographic value in the x-direction.
float	getMinY() Reports the minimum geographic value in the y-direction.
int	getNumLines() Reports the number of line objects that have been read by this reader.
int	getNumPoints() Reports the number of point objects that have been read by this reader.
int	getNumPolys() Reports the number of polygon objects that have been read by this reader.
boolean	read(java.io.InputStream geomInputStream, java.io.InputStream dbInputStream) Reads the given shapefile (requires stream representing the .shp file and the .dbf file).

Methods inherited from class java.lang.Object

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

Constructor Detail

ShapefileReader

public ShapefileReader(processing.core.PApplet parent)

Creates a shapefile reader that will scale any geographic data read to be within the given bounds.

Parameters:

parent - Parent sketch that will draw the data to be read.

Method Detail

read

public boolean read(java.io.InputStream geomInputStream,
                    java.io.InputStream dbInputStream)

Reads the given shapefile (requires stream representing the .shp file and the .dbf file).

Parameters:

geomInputStream - Input stream representing the geometry (.shp) file.

dbInputStream - Input stream representing the attributes (.dbf) file.

Returns:

True if shapefiles were read successfully.

getFeatures

public java.util.Map<java.lang.Integer,Feature> getFeatures()

Provides the features that have been extracted from the shapefile.

Returns:

Map that contains the features indexed by ID.

getAttributes

@Deprecated
public AttributeTable getAttributes()

Deprecated. Use getAttributeTable instead that uses Processing's own Table class to store attributes.

Provides the attribute table that has been extracted from the shapefile. Now this method is deprecated, it may be slower than previously as it creates a new deprecated version of the table each time it is called.

Returns:

Attribute table from shapefile.

getAttributeTable

public processing.data.Table getAttributeTable()

Provides the attribute table that has been extracted from the shapefile.

Returns:

Attribute table from shapefile.

getMinX

public float getMinX()

Reports the minimum geographic value in the x-direction.

Returns:

minimum x value.

getMinY

public float getMinY()

Reports the minimum geographic value in the y-direction.

Returns:

minimum y value.

getMaxX

public float getMaxX()

Reports the maximum geographic value in the x-direction.

Returns:

maximum x value.

getMaxY

public float getMaxY()

Reports the maximum geographic value in the y-direction.

Returns:

maximum y value.

getNumPoints

public int getNumPoints()

Reports the number of point objects that have been read by this reader.

Returns:

Number of point objects read.

getNumLines

public int getNumLines()

Reports the number of line objects that have been read by this reader.

Returns:

Number of line objects read.

getNumPolys

public int getNumPolys()

Reports the number of polygon objects that have been read by this reader. Note that a complex polygon with several parts will be considered a single object.

Returns:

Number of polygon objects read.