Package nz.org.riskscape.engine.task

Interface ReadPageBuffer

All Known Subinterfaces:
PageBuffer
All Known Implementing Classes:
CombinedPageBuffer, LinkedListBuffer
public interface ReadPageBuffer

Buffer that a WorkerTask reads output from. The Tuple input is split into chunks ('pages') to allow for parallelization (i.e. different threads can each work on their own page of input, which they read from this shared input buffer.

  • Method Details

    • isEmpty

      boolean isEmpty()
      Returns:
      true if there are no more pages in the buffer to read (because we're waiting for the upstream worker task to write more).

    • isComplete

      boolean isComplete()
      Returns:
      true if there are no more pages in the buffer to read (because the upstream worker task has finished writing all its output).

    • read

      Page.ReadOnlyPage read()
      Returns:
      a page of Tuples to read, or null if there's no Tuples to read

    • numTuplesRead

      long numTuplesRead()
      Returns:
      the total number of Tuples read from the buffer (for diagnostics).

    • size

      int size()
      Returns:
      the number of unread tuples in unallocated pages in this buffer. It doesn't include the number of tuples that are in pages currently being read.