Interface FeatureCollection<T extends FeatureType,​F extends Feature>

    • Method Detail

      • features

        FeatureIterator<F> features()
        Obtain a FeatureIterator of the Features within this FeatureCollection.

        The implementation of FeatureIterator must adhere to the rules of fail-fast concurrent modification. In addition (to allow for resource backed collections) the FeatureIterator.close() method must be called.

        Example use:

        
         FeatureIterator iterator=collection.features();
         try {
             while( iterator.hasNext()  ){
                  Feature feature = iterator.next();
                  System.out.println( feature.getID() );
             }
         }
         finally {
             iterator.close();
         }
         

        GML Note: The contents of this iterator are considered to be defined by featureMember tags (and/or the single allowed FeatureMembers tag). Please see getFeatureType for more details.

        Returns:
        A FeatureIterator.
      • getSchema

        T getSchema()
        The schema for the child feature members of this collection.

        Represents the most general FeatureType in common to all the features in this collection.

        • For a collection backed by a shapefiles (or database tables) the FeatureType returned by getSchema() will complete describe each and every child in the collection.
        • For mixed content FeatureCollections you will need to check the FeatureType of each Feature as it is retrived from the collection
        • The degenerate case returns the "_Feature" FeatureType, where the only thing known is that the contents are Features.
        Returns:
        FeatureType describing the "common" schema to all child features of this collection
      • getID

        String getID()
        ID used when serializing to GML
      • accepts

        void accepts​(FeatureVisitor visitor,
                     ProgressListener progress)
              throws IOException
        Visit the contents of a feature collection.

        The order of traversal is dependent on the FeatureCollection implementation; some collections are able to make efficient use of an internal index in order to quickly visit features located in the same region.

        Parameters:
        visitor - Closure applied to each feature in turn.
        progress - Used to report progress, may be used to interrupt the operation
        Throws:
        IOException
        Since:
        2.5
      • subCollection

        FeatureCollection<T,​F> subCollection​(Filter filter)
        SimpleFeatureCollection "view" indicated by provided filter.

        The contents of the returned SimpleFeatureCollection are determined by applying the provider Filter to the entire contents of this FeatureCollection. The result is "live" and modifications will be shared.

        This method is used cut down on the number of filter based methods required for a useful SimpleFeatureCollection construct. The FeatureCollections returned really should be considered as a temporary "view" used to control the range of a removeAll, or modify operation.

        Example Use:

        
         collection.subCollection( filter ).clear();
         
        The above recommended use is agreement with the Collections API precident of List.subList( start, end ).

        The results of subCollection:

        • are to be considered unordered
        • may be an ordered FeatureList if requested when sortBy is indicated
        Returns:
        SimpleFeatureCollection identified as subset.
        See Also:
        FeatureList
      • sort

        FeatureCollection<T,​F> sort​(SortBy order)
        Obtained sorted contents.

        This method may not be supported by all implementations, consider the use of FeatureSource.features( Query ).

        Parameters:
        order - Sort order
        Returns:
        FeatureCollection sorted in the indicated order
      • getBounds

        ReferencedEnvelope getBounds()
        Get the total bounds of this collection which is calculated by doing a union of the bounds of each feature inside of it
        Returns:
        An Envelope containing the total bounds of this collection.
      • isEmpty

        boolean isEmpty()
        Returns true if this feature collection contains no features.
        Returns:
        true if this collection contains no features
      • size

        int size()
        Please note this operation may be expensive when working with remote content.
        See Also:
        Collection.size()