Package org.eclipse.rdf4j.collection.factory.api

Interface CollectionFactory

All Superinterfaces:
AutoCloseable
All Known Implementing Classes:
DefaultCollectionFactory, MapDb3CollectionFactory, MapDbCollectionFactory
@InternalUseOnly public interface CollectionFactory extends AutoCloseable
A Factory that may generate optimised and/or disk based collections Factories like this should not be cached but created a new everytime as the closing is important if they are disk based.

  • Method Details

    • close

      void close() throws RDF4JException
      Specified by:
      close in interface AutoCloseable
      Throws:
      RDF4JException

    • createList

      <T> List<T> createList()
      Type Parameters:
      T - of the list
      Returns:
      a list that may be optimised and/or disk based

    • createValueList

      List<Value> createValueList()
      Returns:
      a list that may be optimised and/or disk based for Values only

    • createSet

      <T> Set<T> createSet()
      Type Parameters:
      T - of the set
      Returns:
      a set that may be optimised and/or disk based

    • createSetOfBindingSets

      default Set<BindingSet> createSetOfBindingSets()
      Returns:
      a set that may be optimised and/or disk based

    • createSetOfBindingSets

      Set<BindingSet> createSetOfBindingSets(Supplier<MutableBindingSet> create, Function<String,Predicate<BindingSet>> getHas, Function<String,Function<BindingSet,Value>> getget, Function<String,BiConsumer<Value,MutableBindingSet>> getSet)
      Allows optimizations beyond what would otherwise be possible, regarding disk access and storage.
      Parameters:
      create - a supplier that makes bindingsets
      a - supplier used to create prebound hasBinding predicates
      a - supplier used to create prebound getValue functions
      a - supplier used to create prebound setValue functions
      Returns:
      a set that may be optimised and/or disk based

    • createValueSet

      Set<Value> createValueSet()
      Returns:
      a set that may be optimised and/or disk based for Values

    • createMap

      <K, V> Map<K,V> createMap()
      Type Parameters:
      K - key type
      V - value type
      Returns:
      a map

    • createValueKeyedMap

      <V> Map<Value,V> createValueKeyedMap()
      Type Parameters:
      V - value type
      Returns:
      a map

    • createQueue

      <T> Queue<T> createQueue()
      Type Parameters:
      T - of the contents of the queue
      Returns:
      a new queue

    • createValueQueue

      Queue<Value> createValueQueue()
      Returns:
      a new queue

    • createGroupByMap

      @InternalUseOnly <E> Map<BindingSetKey,E> createGroupByMap()

    • createBindingSetKey

      @InternalUseOnly BindingSetKey createBindingSetKey(BindingSet bindingSet, List<Function<BindingSet,Value>> getValues, ToIntFunction<BindingSet> hashOfBindingSetCalculator)

    • hashAValue

      @InternalUseOnly default int hashAValue(Function<BindingSet,Value> getValue, int nextHash, BindingSet bs)
      Hashes a value that complies with the hashCode/equals conception but only in context of this collection/factory storage layer. Potentially also only valid during a single transaction scope.
      Parameters:
      getValue - the function to extract the value to hash
      nextHash - any previously calculated hash value for earlier values in the BindingSet
      bs - the bindingset to take the value from
      Returns:
      a hash function

    • hashOfBindingSetFuntion

      @InternalUseOnly default ToIntFunction<BindingSet> hashOfBindingSetFuntion(List<Function<BindingSet,Value>> getValues)
      Generate a method that calculates a hash code that is valid in context of a single store implementation and QueryExecutionContext.
      Parameters:
      getValues - that should be considered in the hash
      Returns:
      a hash function