Package org.geotools.process.vector

Class ProcessingCollection<T extends FeatureType,F extends Feature>

Object
BaseFeatureCollection<T,F>
ProcessingCollection<T,F>
Type Parameters:
T -
F -
All Implemented Interfaces:
FeatureCollection<T,F>
Direct Known Subclasses:
SimpleProcessingCollection
public abstract class ProcessingCollection<T extends FeatureType,F extends Feature> extends BaseFeatureCollection<T,F>
Abstract base class to ease the implementation of a streaming processing collection, that is, one that tries to compute the results on the fly as the iterator is traversed.

Besides the few methods that the implementor actually needs to override it suggested to consider overriding also the followings to get extra performance gains:

Author:
Andrea Aime - GeoSolutions

  • Constructor Details

    • ProcessingCollection

      public ProcessingCollection()

  • Method Details

    • features

      public abstract FeatureIterator<F> features()
      Streams out the output features
      Specified by:
      features in interface FeatureCollection<T extends FeatureType,F extends Feature>
      Specified by:
      features in class BaseFeatureCollection<T extends FeatureType,F extends Feature>
      Returns:
      A FeatureIterator.

    • getBounds

      public abstract ReferencedEnvelope getBounds()
      The bounds of features in the output. If the bounds are not known in advance once can call the getFeatureBounds() which will build it from the features as they are returned from the feature iterator.
      Specified by:
      getBounds in interface FeatureCollection<T extends FeatureType,F extends Feature>
      Overrides:
      getBounds in class BaseFeatureCollection<T extends FeatureType,F extends Feature>
      Returns:
      An Envelope containing the total bounds of this collection.

    • buildTargetFeatureType

      protected abstract T buildTargetFeatureType()
      Builds once and for all the target feature type. The results are available by calling getSchema()

    • size

      public abstract int size()
      The number of features in the output. If the size is not known in advance once can call the getFeatureCount() which will count the features as they are returned from the feature iterator.
      Specified by:
      size in interface FeatureCollection<T extends FeatureType,F extends Feature>
      Overrides:
      size in class BaseFeatureCollection<T extends FeatureType,F extends Feature>
      Returns:
      Number of items, or Interger.MAX_VALUE
      See Also:

    • getSchema

      public T getSchema()
      Description copied from interface: FeatureCollection
      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.
      Specified by:
      getSchema in interface FeatureCollection<T extends FeatureType,F extends Feature>
      Overrides:
      getSchema in class BaseFeatureCollection<T extends FeatureType,F extends Feature>
      Returns:
      FeatureType describing the "common" schema to all child features of this collection