prajna.geo

Class KmlWriter

java.lang.Object

prajna.io.WebFormatWriter<GeoShape>

prajna.geo.KmlWriter

All Implemented Interfaces:

FormatWriter<GeoShape>

public class KmlWriter
extends WebFormatWriter<GeoShape>

The KmlWriter is designed to write geographic information to a KML file. It allows adding various GeoShapes and GeoLayers to the writer. Any data record associated with an individual GeoShape is mapped to the description of that KML element in the resulting file.

Author:

Edward Swing

Constructor Summary

Constructors

Constructor and Description
KmlWriter() Construct a KML writer without specifying an output writer
KmlWriter(java.io.Writer writer) Construct a KML writer for the given output stream

Method Summary

Methods

Modifier and Type	Method and Description
void	addGeoLayer(GeoLayer layer) Add a Geographic Layer to the KML file.
void	addShape(GeoShape shape) Add a shape to the KML file.
void	addTimedShape(GeoShape shape, TimeSpan span) Add a shape with a time component.
void	clear() Clear and reset the writer.
void	close() Close the KML file, writing the contents to the specified output stream.
protected org.w3c.dom.Element	createDescription(DataRecord rec) Create a description element.
java.lang.String	getContentType() Get the content type generated by this writer.
void	writeData(java.util.Collection<GeoShape> data) Write a collection of Geoshapes.

Methods inherited from class prajna.io.WebFormatWriter

getDestination, getWriter, setDestination, setWriter

Methods inherited from class java.lang.Object

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

Constructor Detail

KmlWriter

public KmlWriter()

Construct a KML writer without specifying an output writer

KmlWriter

public KmlWriter(java.io.Writer writer)

Construct a KML writer for the given output stream

Parameters:

writer - the writer where the KML file will be written

Method Detail

addGeoLayer

public void addGeoLayer(GeoLayer layer)

Add a Geographic Layer to the KML file. This will create a KML folder element, and each shape contained in the GeoLayer will be added as a separate Placemark. Any associate style information will also be added to the KML document

Parameters:

layer - The Geographic Layer

addShape

public void addShape(GeoShape shape)

Add a shape to the KML file. This results in a Placemark element being added to the document element within the KML file.

Parameters:

shape - the shape to add

addTimedShape

public void addTimedShape(GeoShape shape,
                 TimeSpan span)

Add a shape with a time component. This method creates a Placemark element with the geometric shape and a time primitive element, and adds it to the document within the KML file.

Parameters:

shape - the shape to add

span - The timespan with time information

clear

public void clear()

Clear and reset the writer.

close

public void close()

Close the KML file, writing the contents to the specified output stream.

createDescription

protected org.w3c.dom.Element createDescription(DataRecord rec)

Create a description element. This is used to provide information about a particular geographic entity. If the DataRecord contains neither a link nor any fields, or is null, this method returns null.

Parameters:

rec - the data record used to create the description

Returns:

a description element

getContentType

public java.lang.String getContentType()

Get the content type generated by this writer. This should return a mime type, suitable for web-based data

Overrides:

getContentType in class WebFormatWriter<GeoShape>

Returns:

the String application/vnd.google-earth.kml+xml

writeData

public void writeData(java.util.Collection<GeoShape> data)

Write a collection of Geoshapes. This simply invokes addShape on each shape in the collection

Parameters:

data - the collection of geographic shapes