Package lejos.robotics.mapping

Class ShapefileLoader

java.lang.Object

lejos.robotics.mapping.ShapefileLoader

public class ShapefileLoader
extends java.lang.Object

This class loads map data from a Shapefile and produces a LineMap object, which can be used by the leJOS navigation package.

There are many map editors which can use the Shapefile format (OpenEV, Global Mapper). Once you have created a map, export it as Shapefile. This will produce three files ending in .shp .shx and .dbf. The only file used by this class is .shp.

NOTE: Shapefiles can only contain one type of shape data (polygon or polyline, not both). A single file can't mix polylines with polygons.

This class' code can parse points and multipoints. However, a LineMap object can't deal with points (only lines) so points and multipoints are discarded.

Field Summary

Fields

Modifier and Type	Field and Description
(package private) java.io.DataInputStream	data_is
private static byte	MULTIPOINT
private static byte	NULL_SHAPE
private static byte	POINT
private static byte	POLYGON
private static byte	POLYLINE
private int	SHAPEFILE_ID

Constructor Summary

Constructors

Constructor and Description
ShapefileLoader(java.io.InputStream in) Creates a ShapefileLoader object using an input stream.

Method Summary

Modifier and Type	Method and Description
private double	readLEDouble() Reads a little endian double into a big endian double
private int	readLEInt() Translates a little endian int into a big endian int
private long	readLELong() Translates a little endian long into a big endian long
LineMap	readLineMap() Retrieves a LineMap object from the Shapefile input stream.

Methods inherited from class java.lang.Object

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

Field Detail

NULL_SHAPE

private static final byte NULL_SHAPE

See Also:

Constant Field Values

POINT

private static final byte POINT

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Constant Field Values

POLYLINE

private static final byte POLYLINE

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Constant Field Values

POLYGON

private static final byte POLYGON

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Constant Field Values

MULTIPOINT

private static final byte MULTIPOINT

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Constant Field Values

SHAPEFILE_ID

private final int SHAPEFILE_ID

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Constant Field Values

data_is

java.io.DataInputStream data_is

Constructor Detail

ShapefileLoader

public ShapefileLoader(java.io.InputStream in)

Creates a ShapefileLoader object using an input stream. Likely you will use a FileInputStream which points to the *.shp file containing the map data.

Parameters:

in -

Method Detail

readLineMap

public LineMap readLineMap()
                    throws java.io.IOException

Retrieves a LineMap object from the Shapefile input stream.

Returns:

the line map

Throws:

java.io.IOException

readLEInt

private int readLEInt()
               throws java.io.IOException

Translates a little endian int into a big endian int

Returns:

int A big endian int

Throws:

java.io.IOException

readLEDouble

private final double readLEDouble()
                           throws java.io.IOException

Reads a little endian double into a big endian double

Returns:

double A big endian double

Throws:

java.io.IOException

readLELong

private long readLELong()
                 throws java.io.IOException

Translates a little endian long into a big endian long

Returns:

long A big endian long

Throws:

java.io.IOException