A spatial operator determines whether its geometric arguments satisfy the stated spatial relationship. The operator {@linkplain org.opengis.filter.Filter#evaluate evaluates} to {@code true} if the spatial relationship is satisfied. Otherwise the operator evaluates to {@code false}. The following is adapted from Filter encoding implementation:

{@linkplain org.opengis.filter.spatial.SpatialOperator Spatial operators} are used to test whether the value of a geometric property, potentially referenced using the name of the property, and a (potentially literal) geometric value satisfy the spatial relationship implied by the operator. For example, the {@link org.opengis.filter.spatial.Overlaps} operator evaluates whether the value of the specified geometric property and the specified literal geometric value spatially overlap.

The {@link org.opengis.filter.spatial.BBOX} element is defined as a convenient and more compact way of encoding the very common bounding box constraint based on the {@code gml:Box} geometry. The {@code BBOX} operator should identify all geometries that spatially interact with the box in some manner.

The spatial operators {@link org.opengis.filter.spatial.DWithin} and {@link org.opengis.filter.spatial.Beyond} test whether the value of a geometric property is within or beyond a specified distance of the specified literal geometric value. Distance values are expressed using the {@linkplain org.opengis.filter.spatial.DistanceBufferOperator#getDistance distance} attribute. The content of the distance attribute represents the magnitude of the distance and the {@linkplain org.opengis.filter.spatial.DistanceBufferOperator#getDistanceUnits units} attribute is used to specify the units of measure.