Class GMLWriter

Hierarchy: Object , GMLWriter

public class GMLWriter

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.

Authors:: David Zwiers, Vivid Solutions; Martin Davis

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

public GMLWriter(boolean emitNamespace)

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

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

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

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 - srsName the srsName attribute value

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

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

public void setStartingIndentIndex(int indent)

Sets the starting column index for pretty printing

Parameters:: indent - indent

public void setMaxCoordinatesPerLine(int num)

Sets the number of coordinates printed per line.

Parameters:: num - num

public String write(Geometry geom)

Writes a Geometry in GML2 format to a String.

Parameters:: geom - geom

Returns:: String GML2 Encoded Geometry

public void write(Geometry geom, Writer writer)

Writes a Geometry in GML2 format into a Writer.

Parameters:: geom - geom Geometry to encode; writer - writer Stream to encode to.

Throws:: IOException - IOException