org.relique.jdbc.csv.Expression Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of csvjdbc Show documentation
Show all versions of csvjdbc Show documentation
a Java JDBC driver for reading comma-separated-value files
/*
* CsvJdbc - a JDBC driver for CSV files
* Copyright (C) 2008 Mario Frasca
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
package org.relique.jdbc.csv;
import java.sql.SQLException;
import java.util.List;
import java.util.Map;
import java.util.Set;
public abstract class Expression
{
/**
* @throws SQLException if error evaluating expression.
*/
public Object eval(Map env) throws SQLException
{
return null;
}
public List usedColumns(Set availableColumns)
{
return null;
}
public List aggregateFunctions()
{
return List.of();
}
/**
* Is this a valid expression such as A > 5 or an invalid
* mix of logical and arithmetic such as (A > 5) + 1 that we
* cannot detect during parsing.
* @return true if valid.
*/
public boolean isValid()
{
return true;
}
/**
* Reset aggregate function each time it is used in a subquery.
*/
public void resetAggregateFunctions()
{
}
}
© 2015 - 2024 Weber Informatics LLC | Privacy Policy