com.vividsolutions.jts.geom
Interface CoordinateSequenceFilter

All Known Implementing Classes:
AffineTransformation

public interface CoordinateSequenceFilter

Interface for classeswhich provide operations that can be applied to the coordinates in a CoordinateSequence. A CoordinateSequence filter can either record information about each coordinate or change the coordinate in some way. CoordinateSequence filters can be used to implement such things as coordinate transformations, centroid and envelope computation, and many other functions. For maximum efficiency, the execution of filters can be short-circuited. Geometry classes support the concept of applying a CoordinateSequenceFilter to each CoordinateSequences they contain.

CoordinateSequenceFilter is an example of the Gang-of-Four Visitor pattern.

Version:
1.7
Author:
Martin Davis
See Also:
Geometry.apply(CoordinateSequenceFilter)

Method Summary
 void filter(CoordinateSequence seq, int i)
          Performs an operation on a coordinate in a CoordinateSequence.
 boolean isDone()
          Reports whether the application of this filter can be terminated.
 boolean isGeometryChanged()
          Reports whether the execution of this filter has modified the coordinates of the geometry.
 

Method Detail

filter

public void filter(CoordinateSequence seq,
                   int i)
Performs an operation on a coordinate in a CoordinateSequence.

Parameters:
seq - the CoordinateSequence to which the filter is applied
i - the index of the coordinate to apply the filter to

isDone

public boolean isDone()
Reports whether the application of this filter can be terminated. Once this method returns false, it should continue to return false on every subsequent call.

Returns:
true if the application of this filter can be terminated.

isGeometryChanged

public boolean isGeometryChanged()
Reports whether the execution of this filter has modified the coordinates of the geometry. If so, Geometry.geometryChanged() will be executed.

Most filters can simply return a constant value reflecting whether they are able to change the coordinates.

Returns:
true if this filter has changed the coordinates of the geometry