org.locationtech.jts.io.gml2

Class GMLWriter

java.lang.Object

org.locationtech.jts.io.gml2.GMLWriter

public class GMLWriter
extends Object

Writes Geometrys as XML fragments in GML2 format. Allows specifying the XML prefix, namespace and srsName of the emitted GML. Also allows adding custom root elements to support GML extensions such as KML. With appropriate settings for prefix (none) and custom root elements this class can be used to write out geometry in KML format.

An example of the output that can be generated is:

 <gml:LineString xmlns:gml='http://www.opengis.net/gml' srsName='foo'>
   <gml:coordinates>
     6.03,8.17 7.697,6.959 8.333,5.0 7.697,3.041 6.03,1.83 3.97,1.83 2.303,3.041 1.667,5.0 2.303,6.959 3.97,8.17 
   </gml:coordinates>
 </gml:LineString>
 

This class does not rely on any external XML libraries.

Author:

David Zwiers, Vivid Solutions, Martin Davis

Constructor Summary

Constructors

Constructor and Description
GMLWriter() Creates a writer which outputs GML with default settings.
GMLWriter(boolean emitNamespace) Creates a writer which may emit the GML namespace prefix declaration in the geometry root element.

Method Summary

Modifier and Type	Method and Description
void	setCustomElements(String[] customElements) Specifies a list of custom elements which are written after the opening tag of the root element.
void	setMaxCoordinatesPerLine(int num) Sets the number of coordinates printed per line.
void	setNamespace(boolean emitNamespace) Determines whether a GML namespace declaration will be written in the opening tag of geometries.
void	setPrefix(String prefix) Specifies the namespace prefix to write on each GML tag.
void	setSrsName(String srsName) Sets the value of the srsName attribute to be written into the root geometry tag.
void	setStartingIndentIndex(int indent) Sets the starting column index for pretty printing
String	write(Geometry geom) Writes a Geometry in GML2 format to a String.
void	write(Geometry geom, Writer writer) Writes a Geometry in GML2 format into a Writer.

Methods inherited from class java.lang.Object

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

Constructor Detail

GMLWriter

public GMLWriter()

Creates a writer which outputs GML with default settings. The defaults are:

• the namespace prefix is gml:
• no namespace prefix declaration is written
• no srsName attribute is written

GMLWriter

public GMLWriter(boolean emitNamespace)

Creates a writer which may emit the GML namespace prefix declaration in the geometry root element.

Parameters:

emitNamespace - true if the GML namespace prefix declaration should be written in the geometry root element

Method Detail

setPrefix

public void setPrefix(String prefix)

Specifies the namespace prefix to write on each GML tag. A null or blank prefix may be used to indicate no prefix.

The default is to write gml: as the namespace prefix.

Parameters:

prefix - the namespace prefix to use (null or blank if none)

setSrsName

public void setSrsName(String srsName)

Sets the value of the srsName attribute to be written into the root geometry tag. If the value is null or blank no srsName attribute will be written. The provided value must be a valid XML attribute value - it will not be XML-escaped.

The default is not to write the srsName attribute.

Parameters:

srsName - the srsName attribute value

setNamespace

public void setNamespace(boolean emitNamespace)

Determines whether a GML namespace declaration will be written in the opening tag of geometries. Useful in XML-aware environments which parse the geometries before use, such as XSLT.

Parameters:

emitNamespace - true if the GML namespace prefix declaration should be written in the root geometry element

setCustomElements

public void setCustomElements(String[] customElements)

Specifies a list of custom elements which are written after the opening tag of the root element. The text contained in the string sequence should form valid XML markup. The specified strings are written one per line immediately after the root geometry tag line.

For instance, this is useful for adding KML-specific geometry parameters such as <extrude>

Parameters:

customElements - a list of the custom element strings, or null if none

setStartingIndentIndex

public void setStartingIndentIndex(int indent)

Sets the starting column index for pretty printing

Parameters:

indent -

setMaxCoordinatesPerLine

public void setMaxCoordinatesPerLine(int num)

Sets the number of coordinates printed per line.

Parameters:

num -

write

public String write(Geometry geom)

Writes a Geometry in GML2 format to a String.

Parameters:

geom -

Returns:

String GML2 Encoded Geometry

write

public void write(Geometry geom,
                  Writer writer)
           throws IOException

Writes a Geometry in GML2 format into a Writer.

Parameters:

geom - Geometry to encode

writer - Stream to encode to.

Throws:

IOException