uk.ac.starlink.table.RowPipe Maven / Gradle / Ivy
package uk.ac.starlink.table;
import java.io.IOException;
/**
* TableSink implementation whose returned table reads concurrently from rows
* written into it. Some of the methods may block, and the reading and
* writing have to be done in different threads.
*
* This serves almost the same purpose as a
* {@link uk.ac.starlink.table.RowStore}, but has a subtly different contract.
* Instead of RowStore's {@link uk.ac.starlink.table.RowStore#getStarTable}
* method, which must be called after the endRows method,
* it provides a {@link #waitForStarTable} method which may be called
* before any or all rows have been written, but on a different thread.
* This blocks until the metadata has been supplied.
*
* @author Mark Taylor
* @since 9 Aug 2007
*/
public interface RowPipe extends TableSink {
/**
* Returns a table whose data is supplied by that written into this sink.
* Reads from this table should be called on a separate thread from
* the one which is writing into this sink.
* It will block until {@link #acceptMetadata} has been called.
*
* @return table
*/
StarTable waitForStarTable() throws IOException;
/**
* May be called by the writing stream to set an I/O error on the pipe.
* This error should be passed on to the reading end by throwing an
* error with e as its cause from one of the read methods.
* If an error has already been set by a previous call of this method,
* this has no effect (only the first error is set).
*
* @param e exception to pass to readers
*/
void setError( IOException e );
}