org.h2.index.SingleRowCursor Maven / Gradle / Ivy
/*
* Copyright 2004-2019 H2 Group. Multiple-Licensed under the MPL 2.0,
* and the EPL 1.0 (https://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());
}
}