001 /** 002 * ========================================= 003 * LibFormula : a free Java formula library 004 * ========================================= 005 * 006 * Project Info: http://reporting.pentaho.org/libformula/ 007 * 008 * (C) Copyright 2006-2007, by Pentaho Corporation and Contributors. 009 * 010 * This library is free software; you can redistribute it and/or modify it under the terms 011 * of the GNU Lesser General Public License as published by the Free Software Foundation; 012 * either version 2.1 of the License, or (at your option) any later version. 013 * 014 * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; 015 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 016 * See the GNU Lesser General Public License for more details. 017 * 018 * You should have received a copy of the GNU Lesser General Public License along with this 019 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, 020 * Boston, MA 02111-1307, USA. 021 * 022 * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 023 * in the United States and other countries.] 024 * 025 * 026 * ------------ 027 * $Id: DataTable.java 2716 2007-04-01 13:51:58Z taqua $ 028 * ------------ 029 * (C) Copyright 2006-2007, by Pentaho Corporation. 030 */ 031 package org.jfree.formula.lvalues; 032 033 /** 034 * A database is a two dimensional collection of data, arranged in a table. 035 * Although we do not assume that the whole database is held in memory, we 036 * allow random access of the data. 037 * 038 * Columns may have names, but there is no enforced requirement for that. 039 * 040 * As a database is not just a collection of raw data, this interface returns 041 * LValues instead of plain objects. Columns may be computed values using 042 * formulas (the exact semantics of adressing database cells in a formula is 043 * beyond the scope of this specification and is implementation specific). 044 * 045 * @author Thomas Morgner 046 */ 047 public interface DataTable extends LValue 048 { 049 public int getRowCount(); 050 public int getColumnCount(); 051 052 public String getColumnName (int column); 053 public LValue getValueAt (int row, int column); 054 }