Interface Relation

Method Details

• getType

  Struct getType()

• iterator

  TupleIterator iterator()

• project

  ResultOrProblems<Relation> project(Projection projection)

• restrict

  ResultOrProblems<Relation> restrict(Restriction restriction)

• stream

  default Stream<Tuple> stream()

• getSpatialMetadata

  default Optional<SpatialMetadata> getSpatialMetadata()

  Returns:

  SpatialMetadata for this relation. Should return Optional.empty() if not a spatial layer.

• skipInvalid

  Relation skipInvalid(ProblemSink sendProblemsTo)

  Returns:

  a new relation that skips rows that are invalid for some reason TODO consider whether we need some sort of 'cloneWithOptions' method, that returns a new relation if the options are supported

• hasSkipOnInvalid

  boolean hasSkipOnInvalid()

  Returns:

  true if invalid rows will be skipped for this relation

• getSourceInformation

  String getSourceInformation()

• calculateBounds

  default Optional<org.geotools.geometry.jts.ReferencedEnvelope> calculateBounds()

  Returns:

  a freshly computed ReferencedEnvelope for this relation which covers all of the geometry in the relation identified by its SpatialMetadata, or empty if no SpatialMetadata or for an empty Relation.

• getLimit

  long getLimit()

  Returns:

  The maximum number of Tuples this Relation will yield via an iterator it produces. If the underlying data set is not ordered, this could be a completely arbitrary set of results.

• getOffset

  long getOffset()

  Returns:

  The number of Tuples that will be skipped before an iterator starts yielding results. If the underlying data set is not ordered, this could be a completely arbitrary set of results.

• limit

  default Relation limit(long newLimit)

  Convenience version of limitAndOffset(long, long) with offset set to the Relation's current offset

• offset

  default Relation offset(long newOffset)

  Convenience version of limitAndOffset(long, long) with limit set to the Relation's current limit

• limitAndOffset

  Relation limitAndOffset(long newLimit, long newOffset)

  Returns a new relation that yields a subset of tuples this relation would normally return. This should apply after any filtering that's applied to the relation, even if those filters are applied after a limit and offset.

  Returns:

  a new Relation with the limit and offset applied

• getScalarDataType

  default Type getScalarDataType()

  Description copied from interface: SelfDescribingScalarData

  Returns the RiskScape type that describes this data when extracted from a project and added in to a pipeline as a scalar value.

  It is referred to as the scalar type to make it clear it's not the same as the Type of the data contained within it, e.g. the Struct type of the relation (non-scalar) vs RelationType that represents the relation itself (scalar).

  Specified by:

  getScalarDataType in interface SelfDescribingScalarData

• size

  default Optional<Long> size()

  Get a rough count of the untransformed tuples in the relation. This may include tuples that are skipped because they are invalid or removed by a filter bookmark parameter. A rule of thumb is this should match the number of tuples produced by BaseRelation#rawIterator().

  Returns:

  the number of tuples present in the underlying data (if easily known).