Class CroppedPLL<T>

  • Type Parameters:
    T -

    public class CroppedPLL<T>
    extends PLL<T>
    A PLL obtained by removing some rows at the beginning or the end of a PLL.
    Antonin Delpeuch
    • Field Detail

      • pll

        protected final PLL<T> pll
      • itemsToDrop

        protected final long itemsToDrop
      • atEnd

        protected final boolean atEnd
      • partitionSizes

        protected final io.vavr.collection.Array<Long> partitionSizes
    • Constructor Detail

      • CroppedPLL

        public CroppedPLL​(PLL<T> parent,
                          io.vavr.collection.Array<Long> newPartitionSizes,
                          int partitionsToDrop,
                          long dropItems,
                          boolean atEnd)
        Constructs a cropped PLL by removing rows at the beginning or the end of a PLL.
        parent - the PLL which should be cropped
        newPartitionSizes - the resulting partition sizes after the cropping. This must be provided.
        partitionsToDrop - the number of partitions to be dropped entirely
        dropItems - the number of items to drop in the first partition that is not dropped
        atEnd - false if the partitions and items should be dropped at the beginning, true if at the end
    • Method Detail

      • compute

        protected CloseableIterator<T> compute​(Partition partition)
        Description copied from class: PLL
        Iterate over the elements of the given partition. This is the method that should be implemented by subclasses. As this method forces computation, ignoring any caching, consumers should not call it directly but rather use PLL.iterate(Partition). Once the iterator is not needed anymore, it should be closed. This makes it possible to release the underlying resources supporting it, such as open files or sockets.
        Specified by:
        compute in class PLL<T>
        partition - the partition to iterate over
      • getPartitions

        public io.vavr.collection.Array<? extends Partition> getPartitions()
        Specified by:
        getPartitions in class PLL<T>
        the partitions in this list
      • getParents

        public List<PLL<?>> getParents()
        Description copied from class: PLL
        Returns the PLLs that this PLL depends on, to compute its contents. This is used for debugging purposes, to display the tree of dependencies of a given PLL.
        Specified by:
        getParents in class PLL<T>
        See Also:
      • hasCachedPartitionSizes

        public boolean hasCachedPartitionSizes()
        Description copied from class: PLL
        Is this PLL aware of the size of its partitions?
        hasCachedPartitionSizes in class PLL<T>
      • getDroppedPartitions

        public int getDroppedPartitions()
        The difference between the parents' number of partitions and the new number of partitions in this PLL.