com.luciad.format.nvg.xml

Defense SymbologyClass TLcdNVGModelDecoder

java.lang.Object

com.luciad.format.xml.bind.schema.ALcdXMLModelDecoder

com.luciad.format.nvg.xml.TLcdNVGModelDecoder

All Implemented Interfaces:

ILcdInputStreamFactoryCapable, ILcdModelDecoder

@LcdService(service=ILcdModelDecoder.class,
            priority=20000)
public class TLcdNVGModelDecoder
extends ALcdXMLModelDecoder

Model decoder for Nato Vector Graphics that are encoded in XML. The decoder supports both NVG 1.4, 1.5 or 2.0.

Input files

File	Required	Entry point	Description
*.xml, *.nvg	x	x	NVG XML file

Supported file transfer protocols

• This model decoder supports all transfer protocols that are supported by the ILcdInputStreamFactory of this decoder.

Model structure

• This model decoder creates a model per file.
• All models returned by this model decoder implement ILcd2DBoundsIndexedModel.
• NVG 1.4/1.5 models extend TLcdNVG15Model
• NVG 2.0 models extend TLcdNVG20FilteredModel. This model wrapper provides a time-filtered view on the original data, which extends TLcdNVG20Model

Model descriptor

• All models returned by this model decoder have a TLcdNVGModelDescriptor.
• NVG 1.4/1.5 models have a TLcdNVG15ModelDescriptor
• NVG 2.0 models have a TLcdNVG20ModelDescriptor

Model reference

• All models returned by this model decoder have a default WGS 84 georeference

Model elements

• Each decoded model contains elements that implement ILcdShape and ILcdDataObject
• NVG 2.0 models contain either shapes (e.g. TLcdNVG20Circle), text, groups and composites, or symbolized content
• NVG 1.4/1.5 models contain either shapes (e.g. TLcdNVG15Circle). text, groups and anchors, or data objects

Sample code

   // decode the model
   TLcdNVGModelDecoder decoder = new TLcdNVGModelDecoder();
   TLcdNVG20FilteredModel model = (TLcdNVG20FilteredModel)decoder.decode("nvg20file.xml");

   // update the model to only expose elements of the given date
   model.setDate(aDate);

   // access all model elements, regardless of the date
   TLcdNVG20Model modelWithAllElements = model.getUnfilteredModel()
 

Thread safety

• The decoding of models is thread-safe, as long as no properties are changed during the decoding.
• The decoded models are thread-safe for read access.

Supported versions and specifications

• NATO Vector Graphics Data Format 1.4
• NATO Vector Graphics Data Format 1.5
• NATO Vector Graphics Data Format 2.0

For more information, refer to the TIDE project (Technology for Information, Decision and Execution superiority).

Known limitations

This decoder does not deal with the NATO Vector Graphics (NVG) Protocol web service.

Since:

2015.0

Constructor Summary

Constructors

Constructor and Description
TLcdNVGModelDecoder() Creates a new TLcdNVGModelDecoder , ready to use.

Method Summary

Modifier and Type	Method and Description
boolean	canDecodeSource(String aSourceName) Checks whether this model decoder can decode the specified data source.
ILcdModel	decode(String aSourceName) Creates a new model from the given data source.
String	getDisplayName() Returns a short, displayable name for the format that is decoded by this ILcdModelDecoder.
EntityResolver2	getEntityResolver() Returns the org.xml.sax.ext.EntityResolver2 that is used for creating input sources for XSD schemas.
ILcdInputStreamFactory	getInputStreamFactory() Get the input stream factory of this NVG model decoder.
XMLInputFactory	getXMLInputFactory() Returns the javax.xml.stream.XMLInputFactory that is used by this decoder for creating javax.xml.stream.XMLStreamReader instances.
boolean	isUseApplicationSchemaCache() Returns if application schemas are cached.
void	setEntityResolver(EntityResolver2 aEntityResolver) Sets the org.xml.sax.ext.EntityResolver2 to be used for creating input sources for XSD schemas.
void	setInputStreamFactory(ILcdInputStreamFactory aInputStreamFactory) Set the input stream factory to this NVG model decoder.
void	setUseApplicationSchemaCache(boolean aUseCache) Enables or disables application schema caching depending on the parameter value.
void	setXMLInputFactory(XMLInputFactory aXMLInputFactory) Sets the javax.xml.stream.XMLInputFactory to be used by this decoder for creating javax.xml.stream.XMLStreamReader instances.

Methods inherited from class com.luciad.format.xml.bind.schema.ALcdXMLModelDecoder

decode

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.luciad.model.ILcdModelDecoder

canDecodeSource, decodeModelMetadata, decodeModelMetadata, decodeSource, discoverDataSources

Constructor Detail

TLcdNVGModelDecoder

public TLcdNVGModelDecoder()

Creates a new TLcdNVGModelDecoder , ready to use.

Method Detail

getDisplayName

public String getDisplayName()

Returns a short, displayable name for the format that is decoded by this ILcdModelDecoder.

Returns:

the displayable name of this ILcdModelDecoder.

canDecodeSource

public boolean canDecodeSource(String aSourceName)

Checks whether this model decoder can decode the specified data source. It is acceptable for this method to return true for a source name while decode throws an exception for that same source name.

For performance reasons, we strongly recommend that this will only be a simple test. For example: check the file extension of a file, but not that the file exists or contains expected content.

Parameters:

aSourceName - the data source to be verified; typically a file name or a URL.

Returns:

true if this decoder can likely decode the data specified by the source name, false otherwise.

See Also:

ILcdModelDecoder.decode(String), ILcdModelDecoder.decodeModelMetadata(String)

decode

public ILcdModel decode(String aSourceName)
                 throws IOException

Creates a new model from the given data source.

Parameters:

aSourceName - the data source to be decoded; typically a file name or a URL.

Returns:

A model containing the decoded data. While null is allowed, implementors are advised to throw an error instead.

Throws:

IOException - for any exceptions caused by IO problems or invalid data. Since decoding invalid data almost always results in RunTimeExceptions (NullPointerException, IndexOutOfBoundsException, IllegalArgumentException, ...) on unexpected places, implementations are advised to catch RuntimeExceptions in their decode() method, and wrap them into an IOException, as illustrated in the code snippet below.

   public ILcdModel decode( String aSourceName ) throws IOException {
      try (InputStream input = fInputStreamFactory.createInputStream(aSourceName)) {
         // Perform decoding ...
      } catch (RuntimeException e) {
         throw new IOException(e);
      }
   }
 

InterruptedIOException - When the thread on which this method is called is interrupted: it is recommended to stop the decoding and throw an InterruptedIOException. This same exception can also be used if the decoder shows UI to the user, and the user cancels the decoding through the UI.

See Also:

ILcdModelDecoder.canDecodeSource(String)

setInputStreamFactory

public void setInputStreamFactory(ILcdInputStreamFactory aInputStreamFactory)

Set the input stream factory to this NVG model decoder.

Specified by:

setInputStreamFactory in interface ILcdInputStreamFactoryCapable

Specified by:

setInputStreamFactory in class ALcdXMLModelDecoder

Parameters:

aInputStreamFactory - The input stream factory to set to this decoder.

See Also:

ALcdXMLModelDecoder.getInputStreamFactory()

getXMLInputFactory

public XMLInputFactory getXMLInputFactory()

Description copied from class: ALcdXMLModelDecoder

Returns the javax.xml.stream.XMLInputFactory that is used by this decoder for creating javax.xml.stream.XMLStreamReader instances.

Specified by:

getXMLInputFactory in class ALcdXMLModelDecoder

Returns:

the javax.xml.stream.XMLInputFactory that is used by this decoder for creating javax.xml.stream.XMLStreamReader instances.

setXMLInputFactory

public void setXMLInputFactory(XMLInputFactory aXMLInputFactory)

Description copied from class: ALcdXMLModelDecoder

Sets the javax.xml.stream.XMLInputFactory to be used by this decoder for creating javax.xml.stream.XMLStreamReader instances.

Specified by:

setXMLInputFactory in class ALcdXMLModelDecoder

Parameters:

aXMLInputFactory - the javax.xml.stream.XMLInputFactory to be used by this decoder for creating javax.xml.stream.XMLStreamReader instances.

getEntityResolver

public EntityResolver2 getEntityResolver()

Description copied from class: ALcdXMLModelDecoder

Returns the org.xml.sax.ext.EntityResolver2 that is used for creating input sources for XSD schemas. This entity resolver will only be used to resolve extension schemas that are not already configured on this decoder.

Specified by:

getEntityResolver in class ALcdXMLModelDecoder

Returns:

the entity resolver to be used for creating input sources for XSD schemas.

setEntityResolver

public void setEntityResolver(EntityResolver2 aEntityResolver)

Description copied from class: ALcdXMLModelDecoder

Sets the org.xml.sax.ext.EntityResolver2 to be used for creating input sources for XSD schemas.

When the entity resolver is unable to find a schema (i.e. the resolveEntity method returns null), the ALcdXMLModelDecoder.getInputStreamFactory() is used to create an appropriate input stream for the given system id of the schema.

Specified by:

setEntityResolver in class ALcdXMLModelDecoder

Parameters:

aEntityResolver - the entity resolver to be used for creating input sources for XSD schemas.

isUseApplicationSchemaCache

public boolean isUseApplicationSchemaCache()

Description copied from class: ALcdXMLModelDecoder

Returns if application schemas are cached. When application schemas are cached, the decoder caches all applications schemas it encounters. When a certain schema is referenced during decoding, only if the schema is not found in the cache, it will be resolved. The default is not to cache.

Note that in case multiple application schemas use the same namespace URI, it is not possible to turn on application schema caching because the decoder will not be able to discern between the different schemas.

Specified by:

isUseApplicationSchemaCache in class ALcdXMLModelDecoder

Returns:

if application schemas are cached

setUseApplicationSchemaCache

public void setUseApplicationSchemaCache(boolean aUseCache)

Description copied from class: ALcdXMLModelDecoder

Enables or disables application schema caching depending on the parameter value.

Specified by:

setUseApplicationSchemaCache in class ALcdXMLModelDecoder

Parameters:

aUseCache - if true, application schema caching is turned on. If false, caching is turned off.

getInputStreamFactory

public ILcdInputStreamFactory getInputStreamFactory()

Get the input stream factory of this NVG model decoder.

Specified by:

getInputStreamFactory in interface ILcdInputStreamFactoryCapable

Specified by:

getInputStreamFactory in class ALcdXMLModelDecoder

Returns:

The input stream factory of this decoder.

See Also:

ALcdXMLModelDecoder.setInputStreamFactory(com.luciad.io.ILcdInputStreamFactory)