www.pudn.com > jfreereport-0.8.3f.zip > DataRow.java

/** 
 * ======================================== 
 * JFreeReport : a free Java report library 
 * ======================================== 
 * 
 * Project Info:  http://www.jfree.org/jfreereport/index.html 
 * Project Lead:  Thomas Morgner; 
 * 
 * (C) Copyright 2000-2002, by Simba Management Limited and Contributors. 
 * 
 * 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., 59 Temple Place, Suite 330, 
 * Boston, MA 02111-1307, USA. 
 * 
 * ------------ 
 * DataRow.java 
 * ------------ 
 * (C)opyright 2002, by Thomas Morgner and Contributors. 
 * 
 * Original Author:  Thomas Morgner; 
 * Contributor(s):   David Gilbert (for Simba Management Limited); 
 * 
 * $Id: DataRow.java,v 1.8.2.1 2003/08/24 14:17:59 taqua Exp $ 
 * 
 * Changes 
 * ------- 
 * 27-Jul-2002 : Initial version 
 * 05-Sep-2002 : Documentation 
 * 13-Sep-2002 : Ran checkstyle and fixed reported issues 
 * 07-Nov-2002 : Included an ID-tag into the header for better bug-tracking. 
 * 05-Dec-2002 : Updated Javadocs (DG); 
 * 06-Dec-2002 : Completed ChangeLog 
 * 10-Dec-2002 : more Docs. 
 */ 
 
package com.jrefinery.report; 
 
/** 
 * The datarow is used to access the current row in the TableModel, 
 * Expressions and Functions using a generic interface. 
 * The DataRow is able to detect deadlocks and to check function depencies. 
 * 
 
 * The DataRows depends on a unmodifiable row structure, so it is forbidden to add 
 * new functions and expressions to the report or to modify the tablemodel after 
 * the report processing has started. 
 * 
 
 * ReportProperties can only be queried if they are marked. Marked properties get 
 * enumerated when the report processing starts. Marking properties after that point 
 * has no effect. Removing the property will not remove the column from this datarow, 
 * this DataRow's column will return null when queried in that case. 
 * 
 * @see com.jrefinery.report.function.Expression 
 * @see com.jrefinery.report.function.Function 
 * @see javax.swing.table.TableModel 
 * @author Thomas Morgner 
 */ 
public interface DataRow 
{ 
  /** 
   * Returns the value of the function, expression or column in the tablemodel using the column 
   * number. For functions and expressions, the getValue() method is called and for 
   * columns from the tablemodel the tablemodel method getValueAt(row, column) 
   * gets called. 
   * 
   * @param col  the item index. 
   * 
   * @return the value. 
   */ 
  public Object get(int col); 
 
  /** 
   * Returns the value of the function, expression or column using its specific name. 
   * The given name is translated into a valid column number and the the column is queried. 
   * For functions and expressions, the getValue() method is called and for 
   * columns from the tablemodel the tablemodel method getValueAt(row, column) 
   * gets called. 
   * 
   * @param col  the item index. 
   * 
   * @return the value. 
   * @throws IllegalStateException if the datarow detected a deadlock. 
   */ 
  public Object get(String col) throws IllegalStateException; 
 
  /** 
   * Returns the name of the column, expression or function. For columns from the tablemodel, 
   * the tablemodels getColumnName method is called. For functions, expressions 
   * and report properties the assigned name is returned. 
   * 
   * @param col  the item index. 
   * 
   * @return the name. 
   */ 
  public String getColumnName(int col); 
 
  /** 
   * Returns the column position of the column, expression or function with the given name or 
   * -1 if the given name does not exist in this DataRow. 
   * 
   * @param name  the item name. 
   * 
   * @return the item index. 
   */ 
  public int findColumn(String name); 
 
  /** 
   * Returns the number of columns, expressions and functions and marked ReportProperties 
   * in the report. 
   * 
   * @return the item count. 
   */ 
  public int getColumnCount(); 
}