Examples of FeatureCollection

chunmap.data.feature.FeatureCollection
@author chunquedong
com.simplegeo.client.types.FeatureCollection
com.vividsolutions.jump.feature.FeatureCollection
A collection of Features, with a special method for querying the Features that lie within a given Envelope.
org.geojson.FeatureCollection
org.geoscript.js.feature.FeatureCollection
org.geotools.feature.FeatureCollection
Collection of features, often handled as a result set.
Where possible FeatureCollection is method compatible with {@link Collection}.

SimpleFeatureCollection house rules:
- Each iterator is considered a live connection which must be closed (see example below)
- Features are not specifically ordered within the SimpleFeatureCollection
- Two Feature instances cannot exist with the same {@link FeatureId}
FeatureIterator close

FeatureCollection provides streaming access with the following restriction on the use of {@link FeatureIterator}: You must call {@link FeatureIterator#close()}. This allows FeatureCollection to clean up any operating system resources used to access information.

Example (safe) use:
```
 FeatureIterator iterator = featureCollection.features(); try { while( iterator.hasNext() ){ Feature feature = iterator.next(); System.out.println( feature.getID() ); } } finally { iterator.close(); } 
```
And in Java 7:
```
 try ( FeatureIterator iterator = featureCollection.features() ){ while( iterator.hasNext() ){ Feature feature = iterator.next(); System.out.println( feature.getID() ); } } 
```
Handy Tip: Although many resource backed collections will choose to release resources at when the iterator has reached the end of its contents this is not something you should rely on.

FeatureCollection Implementation Tips

Auto close: Try and close up resources when you can detect that an Iterator is no longer in use.

Lazy Connect: FeatureCollection is used in two fashions, as a result set, where each iterator acts as a cursor over the content. Also as a predefined query which can be refined further. An example is using featureCollection.subCollection( Filter ) or featureCollection.sort( SortBy ) before listing features out of a FeatureCollection.
@see org.geotools.Feature @author Ian Turton, CCG @author Rob Hranac, VFNY @author Ian Schneider, USDA-ARS @author Jody Garnett, LISAsoft @source $URL$ @version $Id$

Examples of org.geotools.feature.FeatureCollection

        {
            FeatureType fType = mappingDataStore.getSchema(typeName);
            assertNotNull(fType);
            fSource = mappingDataStore.getFeatureSource(typeName);
        }
        FeatureCollection features;
        // make a getFeatures request with a nested properties filter.
        //
        // was 96, but now 3 as mapped features are grouped by id
        final int EXPECTED_MAPPED_FEATURE_COUNT = 3;
        // 96 data rows from property file
        final int EXPECTED_SIMPLE_FEATURE_COUNT = 96;
        {
            features = fSource.getFeatures();


            int resultCount = getCount(features);
            String msg = "be sure difference in result count is not due to different dataset.";
            assertEquals(msg, EXPECTED_MAPPED_FEATURE_COUNT, resultCount);
        }


        Feature feature;
        int count = 0;


        FilterFactory ffac;
        {
            NamespaceSupport namespaces = new NamespaceSupport();
            namespaces.declarePrefix("aw", AWNS);
            namespaces.declarePrefix("om", OMNS);
            namespaces.declarePrefix("swe", SWENS);
            namespaces.declarePrefix("gml", GMLNS);
            namespaces.declarePrefix("sa", SANS);
            namespaces.declarePrefix("cv", CVNS);
            // TODO: use commonfactoryfinder or the mechanism choosed
            // to pass namespace context to filter factory
            ffac = new FilterFactoryImplNamespaceAware(namespaces);
        }


        final String phenomNamePath = "aw:relatedObservation/aw:PhenomenonTimeSeries/om:observedProperty/swe:Phenomenon/gml:name";
        FeatureIterator it = features.features();
        for (; it.hasNext();) {
            feature = (Feature) it.next();
            count++;
            {
                PropertyName gmlName = ffac.property("gml:name");
                PropertyName phenomName = ffac.property(phenomNamePath);


                Object nameVal = gmlName.evaluate(feature, String.class);
                assertNotNull("gml:name evaluated to null", nameVal);


                Object phenomNameVal = phenomName.evaluate(feature, String.class);
                assertNotNull(phenomNamePath + " evaluated to null", phenomNameVal);
            }
            {
                PropertyName sampledFeatureName = ffac.property("sa:sampledFeature");
                Attribute sampledFeatureVal = (Attribute) sampledFeatureName.evaluate(feature);
                assertNotNull("sa:sampledFeature evaluated to null", sampledFeatureVal);
                assertEquals(0, ((Collection) sampledFeatureVal.getValue()).size());
                Map attributes = (Map) sampledFeatureVal.getUserData().get(Attributes.class);
                assertNotNull(attributes);
                Name xlinkTitle = name(XLINK.NAMESPACE, "title");
                assertTrue(attributes.containsKey(xlinkTitle));
                assertNotNull(attributes.get(xlinkTitle));


                Name xlinkHref = name(XLINK.NAMESPACE, "href");
                assertTrue(attributes.containsKey(xlinkHref));
                assertNotNull(attributes.get(xlinkHref));
            }


            {
                final String elementPath = "aw:relatedObservation/aw:PhenomenonTimeSeries/om:result/cv:CompactDiscreteTimeCoverage";
                PropertyName elementName = ffac.property(elementPath);
                Object timeCovVal = elementName.evaluate(feature);
                assertNotNull(elementPath, timeCovVal);
                assertTrue(timeCovVal instanceof Feature);
                final List elements = (List) ((Feature) timeCovVal).getValue();
                assertEquals(1, elements.size());
            }


        }
        it.close();


        count = 0;
        FeatureIterator<? extends Feature> simpleIterator = ((AbstractMappingFeatureIterator) features.features()).getSourceFeatureIterator();
        for (; simpleIterator.hasNext();) {
            feature = (Feature) simpleIterator.next();
            count++;


            if (count == 22) {

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Examples of FeatureCollection

FeatureIterator close

FeatureCollection Implementation Tips

Examples of org.geotools.feature.FeatureCollection