Package uk.ac.starlink.table.storage

Class ListRowStore

java.lang.Object
uk.ac.starlink.table.storage.ListRowStore
All Implemented Interfaces:
RowStore, TableSink
public class ListRowStore extends Object implements RowStore
Implementation of RowStore which stores data in memory. The current implementation uses a RowListStarTable. This is better-behaved than the RowStore contract requires; it is guaranteed to be able to store any StarTable object (acceptMetadata(uk.ac.starlink.table.StarTable) will not throw a TableFormatException). Cautious users of this class will note the fact that for large tables, acceptRow(java.lang.Object[]) may throw an OutOfMemoryError.
Since:
3 Aug 2004
Author:
Mark Taylor (Starlink)

  • Constructor Details

    • ListRowStore

      public ListRowStore()

  • Method Details

    • acceptMetadata

      public void acceptMetadata(StarTable meta)
      Description copied from interface: TableSink
      Takes delivery of a row-less StarTable object which defines the metadata of the table to be transmitted. If the number of rows that will be transmitted via subsequent calls to acceptRow is known, this value should be made available as the row count of meta (StarTable.getRowCount()); if it is not known, the row count should be -1. However, this object should not attempt to read any of meta's cell data.

      The data to be transmitted in subsequent calls of acceptRow must match the metadata transmitted in this call in the same way that rows of a StarTable must match its own metadata (number and content clases of columns etc). If this sink cannot dispose of a table corresponding to meta then it may throw a TableFormatException - this may be the case if for instance meta has columns with types that this sink can't deal with.

      Specified by:
      acceptMetadata in interface TableSink
      Parameters:
      meta - table metadata object

    • acceptRow

      public void acceptRow(Object[] row) throws IOException
      Accepts a row.
      Specified by:
      acceptRow in interface TableSink
      Parameters:
      row - table data row
      Throws:
      OutOfMemoryError - if it's run out of memory
      IOException

    • endRows

      public void endRows()
      Description copied from interface: TableSink
      Signals that there are no more rows to be transmitted.
      Specified by:
      endRows in interface TableSink

    • getStarTable

      public StarTable getStarTable()
      Description copied from interface: RowStore
      Obtains a StarTable which contains the data and metadata that have been written into this sink. In general it is only legal to call this method following a call to TableSink.endRows(); failing to observe this sequence may earn you an IllegalStateException
      Specified by:
      getStarTable in interface RowStore
      Returns:
      a random-access StarTable containing the written rows