uk.ac.starlink.table

Interface TableSink

All Known Subinterfaces:

RowPipe, RowStore

All Known Implementing Classes:

ByteStoreRowStore, CacheRowPipe, DiscardRowStore, DiskRowStore, FitsHandler, LimitRowSink, ListRowStore, OnceRowPipe, ProgressBarTableSink, SidewaysRowStore, StreamTableSink

public interface TableSink

Defines a set of callbacks to consume the information held in a StarTable. This may be used to transmit a table from one place to another in one go (passing a StarTable argument may be unsuitable in that it requires the row sequence to be accessible multiple times). Any source which uses this interface must do so in the following sequence:

1. Call acceptMetadata(uk.ac.starlink.table.StarTable) once
2. Call acceptRow(java.lang.Object[]) once for each row in the table
3. Call endRows() once

Implementations are under no obligation to behave sensibly if this sequence is not observed.

Author:

Mark Taylor

Method Summary

Modifier and Type	Method and Description
void	acceptMetadata(StarTable meta) Takes delivery of a row-less StarTable object which defines the metadata of the table to be transmitted.
void	acceptRow(Object[] row) Takes delivery of one row of data.
void	endRows() Signals that there are no more rows to be transmitted.

Method Detail

acceptMetadata

void acceptMetadata(StarTable meta)
             throws TableFormatException

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.

Parameters:

meta - table metadata object

Throws:

TableFormatException - if this sink cannot accept table rows matching the given metadata

acceptRow

void acceptRow(Object[] row)
        throws IOException

Takes delivery of one row of data. row is an array of objects comprising the contents of one row of the table being transmitted. The number and classes of the elements of row are described by the metadata object previously accepted.

Parameters:

row - table data row

Throws:

IOException

endRows

void endRows()
      throws IOException

Signals that there are no more rows to be transmitted.

Throws:

IOException