org.eigenbase.runtime
Class ResultSetTupleIter

java.lang.Object
  org.eigenbase.runtime.AbstractTupleIter
      org.eigenbase.runtime.ResultSetTupleIter

All Implemented Interfaces:

TupleIter, ClosableAllocation

public class ResultSetTupleIter
extends AbstractTupleIter

A ResultSetTupleIter is an adapter which converts a ResultSet to a TupleIter.

Nested Class Summary

Nested classes/interfaces inherited from interface org.eigenbase.runtime.TupleIter

TupleIter.NoDataReason, TupleIter.TimeoutException

Field Summary

private boolean	endOfStream
protected ResultSet	resultSet
private Object	row

Fields inherited from interface org.eigenbase.runtime.TupleIter

EMPTY_ITERATOR

Constructor Summary

ResultSetTupleIter(ResultSet resultSet)

Method Summary

void	closeAllocation() Closes this object.
Object	fetchNext() Returns the next element in the iteration.
protected Object	makeRow() Creates an object representing the current row of the result set.
private void	moveToNext()
void	restart() Restarts this iterator, so that a subsequent call to TupleIter.fetchNext() returns the first element in the collection being iterated.

Methods inherited from class org.eigenbase.runtime.AbstractTupleIter

setTimeout

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

resultSet

protected ResultSet resultSet

row

private Object row

endOfStream

private boolean endOfStream

Constructor Detail

ResultSetTupleIter

public ResultSetTupleIter(ResultSet resultSet)

Method Detail

fetchNext

public Object fetchNext()

Description copied from interface: TupleIter

Returns the next element in the iteration. If there is no next value, it returns a value from the TupleIter.NoDataReason enumeration indicating why no data was returned.

If this method returns TupleIter.NoDataReason.END_OF_DATA, no further data will be returned by this iterator unless TupleIter.restart() is called.

If this method returns TupleIter.NoDataReason.UNDERFLOW, no data is currently available, but may be come available in the future. It is possible for consecutive calls to return UNDERFLOW and then END_OF_DATA.

The object returned by this method may be re-used for each subsequent call to fetchNext(). In other words, callers must either make certain that the returned value is no longer needed or is copied before any subsequent calls to fetchNext().

Returns:

the next element in the iteration, or an instance of TupleIter.NoDataReason.

restart

public void restart()

Description copied from interface: TupleIter

Restarts this iterator, so that a subsequent call to TupleIter.fetchNext() returns the first element in the collection being iterated.

Specified by:

restart in interface TupleIter

Overrides:

restart in class AbstractTupleIter

closeAllocation

public void closeAllocation()

Description copied from interface: ClosableAllocation

Closes this object.

makeRow

protected Object makeRow()
                  throws SQLException

Creates an object representing the current row of the result set. The default implementation of this method returns a Row, but derived classes may override this.

Throws:

SQLException

moveToNext

private void moveToNext()