/*
* Copyright 2004-2018 H2 Group. Multiple-Licensed under the MPL 2.0,
* and the EPL 1.0 (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.index;
import org.h2.message.
DbException;
import org.h2.result.
Row;
import org.h2.result.
SearchRow;
/**
* A cursor with at most one row.
*/
public class
SingleRowCursor implements
Cursor {
private
Row row;
private boolean
end;
/**
* Create a new cursor.
*
* @param row - the single row (if null then cursor is empty)
*/
public
SingleRowCursor(
Row row) {
this.
row =
row;
}
@
Override
public
Row get() {
return
row;
}
@
Override
public
SearchRow getSearchRow() {
return
row;
}
@
Override
public boolean
next() {
if (
row == null ||
end) {
row = null;
return false;
}
end = true;
return true;
}
@
Override
public boolean
previous() {
throw
DbException.
throwInternalError(
toString());
}
}