Class NonReducibleCompositeItem

  • All Implemented Interfaces:
    Cloneable
    Direct Known Subclasses:
    SameElementItem, WeakAndItem

    public abstract class NonReducibleCompositeItem
    extends CompositeItem
    A composite item which specifies semantics which are not maintained if an instance with a single child is replaced by the single child. Most composites, like AND and OR, are reducible as e.g (AND a) is semantically equal to (a). This type functions as a marker type for query rewriters.
    Author:
    bratseth
    • Constructor Detail

      • NonReducibleCompositeItem

        public NonReducibleCompositeItem()
    • Method Detail

      • extractSingleChild

        public Optional<Item> extractSingleChild()
        Description copied from class: CompositeItem
        Will return its single child if itself can safely be omitted.
        Overrides:
        extractSingleChild in class CompositeItem
        Returns:
        a valid Item or empty Optional if it can not be done