| java.lang.Object
 org.xml.sax.helpers.DefaultHandler
com.vividsolutions.jump.io.GMLReader
| GMLReader | | public class GMLReader extends DefaultHandler implements JUMPReader(Code) | | GMLReader is a
JUMPReader specialized to read GML files.
DataProperties for the JCSReader load(DataProperties) interface:
| Parameter |
Meaning |
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File or DefaultValue
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File name for the input .xml file
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InputTemplateFile
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Filename for the GMLInputTemplate .xml file
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| CompressedFile |
File name (a .zip or .gz) with a .jml/.xml/.gml inside
(specified by File)
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CompressedFileTemplate | File name (.zip or .gz)
with the input template in (specified by InputTemplateFile)
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NOTE: If InputTemplateFile is unspecified, GMLReader will try to read one
off the top of the input .xml file (the JCS format). This is the same as
specifying the File and TemplateFile to be the same.
Typically, you would write:
gmlReader = new GMLReader();
gmlReader.load( DriverProperties) ; // has InputFile and InputTemplate
or:
gmlReader.setInputTemplate( GMLInputTemplate);
gmlReader.load( , );
Internal Details - This is based on a small finite state machine with these
states:
STATE MEANING
0 Init
1 Waiting for Collection tag
2 Waiting for Feature tag
3 Getting jcs columns
4 Parsing geometry (goes back to state 3)
1000 Parsing Multi-geometry, recursion level =1
1001 Parsing Multi-geometry, recursion level =2
...
State Diagram
init
0 -----> 1
|
| Collection start Tag
|
-->2----------------> FINISH
\ | End Collection tag
End Feature tag \ |
\|
4<-------->3
Geometry start/end
For multi-geometries
On start Multi-geometry, increment state by 1 (or jump to 1000 if at state
4)
make sure recursivegeometry[state-1000] is null
on end multi-geometry,
build geometry in recursivegeometry[state-1000], add it to
recursivegeometry[state-1000-1]
state= state-1
For single geometries - they will be stuck into recursivegeometry[0], which
is the same
as geometry
For multi geometries - they will also be stuck into recursivegeometry[0],
which is the same
as geometry. But, for the first nested geometry, it will be stuck into
recursivegeometry[1],
which will then be geometry
example of double GCs:
START geometry ->move to state 4
START TAG: multi* -> move to state 1000, geometry = recursivegeometry[0]
-> added to geometry
-> added to geometry START TAG: multi* -> move to state 1001, geometry =
recursivegeometry[1]
-> added to geometry
-> added to geometry END TAG: multi -> move to state 1000, build geometry in
recursivegeometry[1], add to recursivegeometry[0], geometry =
recursivegeometry[0]
-> added to geometry END TAG: multi -> move to state 4, build
geometry in recursivegeometry[0] (thats the result) and put it in
finalGeometry END geometry -> add to feature collection example of simple
geometry: START geometry ->move to state 4 BEGIN polygon ->clear out inner
ring accumulator BEGIN outerboundary BEGIN linearring END linearring -> put
points in linearRing END outerboundary -> put linearRing in outerBoundary
BEGIN innerboundary BEGIN linearring END linearring -> put points in
linearRing END innerboundary -> add linearRing to innerBoundary list END
polygon -> build polygon (put in geometry, which is recursivegeometry[0] END
geometry => add to feature collection
Most of the work is done in the endTag method!
New additions: Jan 2005 by Dave Blasby
allow srid to be parsed from the GML file
For example:
....
The SRID of the created geometry will be 42102.
It accepts srsNames of the form ":".
ie. "EPSG:111" or "DAVE:222" or "BCGOV:333" etc...
The Geometry's SRID will be the number.
If you have a GEOMETRYCOLLECTION with more than one SRID specified
the SRID of the result will be indeterminate (this isnt correct GML).
Geometries without a srsName will get SRID 0.
This functionality defaults to off for compatibility.
To turn it on or off, call the acceptSRID(true|false) function.
New Addition: Jan, 2005by Dave Blasby
Added slightly better support for type=OBJECT. It sticks a String in. Before it would probably throw an error.
Added support for multi-objects for example:
...1...
...2...
...3...
Old behavior would be to for column 'b' to have value "...3...".
New behavior (only if you set b's type to 'OBJECT' and set the GMLReader to processMultiItems as lists)
...1... --> b get the string "...1..." (as before)
...1......2......3... --> 'b' is a list of String ['...1...','...2...','...3...']
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| Constructor Summary | |
| public | GMLReader()
Constructor - make a SAXParser and have this GMLReader be its
ContentHandler and ErrorHandler. |
| STATE_GET_COLUMNS | | static int STATE_GET_COLUMNS(Code) | | |
| STATE_INIT | | static int STATE_INIT(Code) | | STATE MEANING
0 Init
1 Waiting for Collection tag
2 Waiting for Feature tag
3 Getting jcs columns
4 Parsing geometry (goes back to state 3)
1000 Parsing Multi-geometry, recursion level =1
1001 Parsing Multi-geometry, recursion level =2
|
| STATE_PARSE_GEOM_NESTED | | static int STATE_PARSE_GEOM_NESTED(Code) | | |
| STATE_PARSE_GEOM_SIMPLE | | static int STATE_PARSE_GEOM_SIMPLE(Code) | | |
| STATE_WAIT_COLLECTION_TAG | | static int STATE_WAIT_COLLECTION_TAG(Code) | | |
| STATE_WAIT_FEATURE_TAG | | static int STATE_WAIT_FEATURE_TAG(Code) | | |
| currentGeometryNumb | | int currentGeometryNumb(Code) | | |
| finalGeometry | | Geometry finalGeometry(Code) | | |
| geometryFactory | | GeometryFactory geometryFactory(Code) | | |
| lineString | | LineString lineString(Code) | | |
| linearRing | | LinearRing linearRing(Code) | | |
| multiItemsAsLists | | public boolean multiItemsAsLists(Code) | | true => for 'OBJECT' types, if you find more than 1 item, make a list and store all the results
|
| outerBoundary | | LinearRing outerBoundary(Code) | | |
| parseSRID | | public boolean parseSRID(Code) | | |
| singleCoordinate | | Coordinate singleCoordinate(Code) | | |
| GMLReader | | public GMLReader()(Code) | | Constructor - make a SAXParser and have this GMLReader be its
ContentHandler and ErrorHandler.
|
| acceptSRID | | public void acceptSRID(boolean parseTheSRID)(Code) | | parse SRID information in geometry tags
Parameters:
parseTheSRID - true = parse |
| characters | | public void characters(char[] ch, int start, int length) throws SAXException(Code) | | SAX handler - store and accumulate tag bodies
Parameters:
ch - Description of the Parameter
Parameters:
start - Description of the Parameter
Parameters:
length - Description of the Parameter
exception:
SAXException - Description of the Exception |
| endDocument | | public void endDocument()(Code) | | SAX HANDLER - move to state 0
|
| endElement | | public void endElement(String uri, String name, String qName) throws SAXException(Code) | | SAX handler - handle state information and transitions based on ending
elements Most of the work of the parser is done here.
Parameters:
uri - Description of the Parameter
Parameters:
name - Description of the Parameter
Parameters:
qName - Description of the Parameter
exception:
SAXException - Description of the Exception |
| processMultiItems | | public void processMultiItems(boolean accept)(Code) | | Added slightly better support for type=OBJECT. It sticks a String in. Before it would probably throw an error.
Added support for multi-objects for example:
...1...
...2...
...3...
Old behavior would be to for column 'b' to have value "...3...".
New behavior (only if you set b's type to 'OBJECT' and set the GMLReader to processMultiItems as lists)
...1... --> b get the string "b" (as before)
...1......2......3... --> 'b' is a list of String ['...1...','...2...','...3...']
|
| read | | public FeatureCollection read(java.io.Reader r) throws Exception(Code) | | Helper function - calls read(java.io.Reader r,String readerName) with the
readerName "Unknown Stream". You should have already called
setInputTempalate().
Parameters:
r - reader to read the GML File from Description of the Return Value
exception:
Exception - Description of the Exception |
| read | | public FeatureCollection read(java.io.Reader r, String readerName) throws Exception(Code) | | Main function to read a GML file. You should have already called
setInputTempalate().
Parameters:
r - reader to read the GML File from
Parameters:
readerName - what to call the reader for error reporting Description of the Return Value
exception:
Exception - Description of the Exception |
| setInputTemplate | | public void setInputTemplate(GMLInputTemplate template)(Code) | | Attach a GMLInputTemplate information class.
Parameters:
template - The new inputTemplate value |
| startDocument | | public void startDocument()(Code) | | SAX handler - move to state 1
|
| startElement | | public void startElement(String uri, String name, String qName, Attributes atts) throws SAXException(Code) | | SAX handler. Handle state and state transitions based on an element
starting
Parameters:
uri - Description of the Parameter
Parameters:
name - Description of the Parameter
Parameters:
qName - Description of the Parameter
Parameters:
atts - Description of the Parameter
exception:
SAXException - Description of the Exception |
| Methods inherited from org.xml.sax.helpers.DefaultHandler | public void characters(char ch, int start, int length) throws SAXException(Code)(Java Doc)
public void endDocument() throws SAXException(Code)(Java Doc)
public void endElement(String uri, String localName, String qName) throws SAXException(Code)(Java Doc)
public void endPrefixMapping(String prefix) throws SAXException(Code)(Java Doc)
public void error(SAXParseException e) throws SAXException(Code)(Java Doc)
public void fatalError(SAXParseException e) throws SAXException(Code)(Java Doc)
public void ignorableWhitespace(char ch, int start, int length) throws SAXException(Code)(Java Doc)
public void notationDecl(String name, String publicId, String systemId) throws SAXException(Code)(Java Doc)
public void processingInstruction(String target, String data) throws SAXException(Code)(Java Doc)
public InputSource resolveEntity(String publicId, String systemId) throws IOException, SAXException(Code)(Java Doc)
public void setDocumentLocator(Locator locator)(Code)(Java Doc)
public void skippedEntity(String name) throws SAXException(Code)(Java Doc)
public void startDocument() throws SAXException(Code)(Java Doc)
public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException(Code)(Java Doc)
public void startPrefixMapping(String prefix, String uri) throws SAXException(Code)(Java Doc)
public void unparsedEntityDecl(String name, String publicId, String systemId, String notationName) throws SAXException(Code)(Java Doc)
public void warning(SAXParseException e) throws SAXException(Code)(Java Doc)
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