Class GML

  • public class GML
    extends Object
    UtilityClass for encoding GML content.

    This utility class uses a range of GeoTools technologies as required; if you would like finer grain control over the encoding process please review the source code of this class and take your own measures.

    • Constructor Detail

      • GML

        public GML​(GML.Version version)
        Construct a GML utility class to work with the indicated version of GML.

        Note that when working with GML2 you need to supply additional information prior to use (in order to indicate where for XSD file is located).

        version - Version of GML to use
    • Method Detail

      • setLegacy

        public void setLegacy​(boolean legacy)
        Engage legacy support for GML2.

        The GML2 support for FeatureTransformer is much faster then that provided by the GTXML parser/encoder. This speed is at the expense of getting the up front configuration exactly correct (something you can only tell when parsing the produced result!). Setting this value to false will use the same GMLConfiguration employed when parsing and has less risk of producing invalid content.

      • setNamespace

        public void setNamespace​(String prefix,
                                 String namespace)
        Set the target namespace for the encoding.
      • setEncoding

        public void setEncoding​(Charset encoding)
        Set the encoding to use.
      • setBaseURL

        public void setBaseURL​(URL baseURL)
        Base URL to use when encoding
      • setCoordinateReferenceSystem

        public void setCoordinateReferenceSystem​(CoordinateReferenceSystem crs)
        Coordinate reference system to use when decoding.

        In a few cases (such as decoding a SimpleFeatureType) the file format does not include the required CooridinateReferenceSystem and you are asked to supply it.

      • init

        protected void init()
        Set up out of the box configuration for GML encoding.
        • GML2
        • GML3
        The following are not avialable yet:
        • gml3.2 - not yet available
        • wfs1.0 - not yet available
        • wfs1.1 - not yet available
      • encode

        public void encode​(OutputStream out,
                           SimpleFeatureType simpleFeatureType)
                    throws IOException
        Encode the provided SimpleFeatureType into an XSD file, using a target namespace

        When encoding the simpleFeatureType:

        • target prefix/namespace can be provided by prefix and namespace parameters. This is the default for the entire XSD document.
        • simpleFeatureType.geName().getNamespaceURI() is used for the simpleFeatureType itself, providing simpleFeatureType.getUserData().get("prefix") is defined
        simpleFeatureType - To be encoded as an XSD document
      • decodeSimpleFeatureType

        public SimpleFeatureType decodeSimpleFeatureType​(URL schemaLocation,
                                                         Name typeName)
                                                  throws IOException
        Decode a typeName from the provided schemaLocation.

        The XMLSchema does not include CoordinateReferenceSystem we need to ask you to supply this information.

      • decodeFeatureIterator

        public SimpleFeatureIterator decodeFeatureIterator​(InputStream in,
                                                           QName elementName)
                                                    throws IOException,
        Allow the parsing of features as a stream; the returned iterator can be used to step through the inputstream of content one feature at a time without loading everything into memory.

        The use of an elementName is optional; and can be used as a workaround in cases where the schema is not available or correctly defined. The returned elements are wrapped up as a Feature if needed. This mehtod can be used to retrive only the Geometry elements from a GML docuemnt.

        in - InputStream used as a source of SimpleFeature content
        elementName - The simple feature element; the schema will be checked for an entry that extends AbstratFeatureType
      • iterator

        protected SimpleFeatureIterator iterator​(StreamingParser parser)
        Used to wrap up a StreamingParser as a Iterator.

        This iterator is actually forgiving; and willing to "morph" content into a SimpleFeature if needed.

        • SimpleFeature - is returned as is
      • simpleFeature

        protected SimpleFeature simpleFeature​(Object obj,
                                              SimpleFeatureType schema)
        Morph provided obj to a SimpleFeature if possible.
        SimpleFeature, or null if not possible
      • xsd

        protected XSDComplexTypeDefinition xsd​(XSDSchema xsd,
                                               ComplexType type,
                                               XSDComplexTypeDefinition BASE_TYPE)
        Build the XSD definition for the provided type.

        The generated definition is recorded in the XSDSchema prior to being returned.

        xsd - The XSDSchema being worked on
        type - ComplexType to capture as an encoding, usually a SimpleFeatureType
        BASE_TYPE - definition to use as the base type, or null
        XSDComplexTypeDefinition generated for the provided type