Source for org.jfree.formula.parser.FormulaParser

   1: /**
   2:  * =========================================
   3:  * LibFormula : a free Java formula library
   4:  * =========================================
   5:  *
   6:  * Project Info:  http://reporting.pentaho.org/libformula/
   7:  *
   8:  * (C) Copyright 2006-2007, by Pentaho Corporation and Contributors.
   9:  *
  10:  * This library is free software; you can redistribute it and/or modify it under the terms
  11:  * of the GNU Lesser General Public License as published by the Free Software Foundation;
  12:  * either version 2.1 of the License, or (at your option) any later version.
  13:  *
  14:  * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
  15:  * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  16:  * See the GNU Lesser General Public License for more details.
  17:  *
  18:  * You should have received a copy of the GNU Lesser General Public License along with this
  19:  * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  20:  * Boston, MA 02111-1307, USA.
  21:  *
  22:  * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
  23:  * in the United States and other countries.]
  24:  *
  25:  *
  26:  * ------------
  27:  * $Id: FormulaParser.java 3521 2007-10-16 10:55:14Z tmorgner $
  28:  * ------------
  29:  * (C) Copyright 2006-2007, by Pentaho Corporation.
  30:  */
  31: package org.jfree.formula.parser;
  32: 
  33: import java.io.StringReader;
  34: 
  35: import org.jfree.formula.DefaultFormulaContext;
  36: import org.jfree.formula.EvaluationException;
  37: import org.jfree.formula.LibFormulaBoot;
  38: import org.jfree.formula.lvalues.LValue;
  39: import org.jfree.formula.operators.DefaultOperatorFactory;
  40: import org.jfree.formula.operators.OperatorFactory;
  41: 
  42: public class FormulaParser extends GeneratedFormulaParser
  43: {
  44:   // This is my parser class
  45:   private OperatorFactory operatorFactory;
  46: 
  47:   public FormulaParser()
  48:   {
  49:     super(new StringReader(""));
  50:     operatorFactory = new DefaultOperatorFactory();
  51:     operatorFactory.initalize(LibFormulaBoot.getInstance().getGlobalConfig());
  52:   }
  53: 
  54:   protected OperatorFactory getOperatorFactory()
  55:   {
  56:     return operatorFactory;
  57:   }
  58: 
  59:   public LValue parse(final String formula) throws ParseException
  60:   {
  61:     if (formula == null)
  62:     {
  63:       throw new NullPointerException("Formula-text given must not be null.");
  64:     }
  65:     ReInit(new StringReader(formula));
  66:     return getExpression();
  67:   }
  68: 
  69:   public static void main(final String[] args)
  70:       throws ParseException, EvaluationException
  71:   {
  72:     final FormulaParser parser = new FormulaParser();
  73: 
  74:     //    x = parser.parse("1 * 2 + 3 * 4");
  75: //    x.initialize(new DefaultFormulaContext());
  76: //    System.out.println(x);
  77: //
  78: //    x = parser.parse("[a] * [b] + [c] * [d]");
  79: //    x.initialize(new DefaultFormulaContext());
  80: //    System.out.println(x);
  81: //
  82: //    x = parser.parse("IF([A];[B];[C])");
  83: //    x.initialize(new DefaultFormulaContext());
  84: //    System.out.println(x);
  85: //
  86: //    x = parser.parse("1 + ( 2+ (3 + (400 + 200)))");
  87: //    x.initialize(new DefaultFormulaContext());
  88: //    System.out.println(x);
  89: 
  90:     final LValue x = parser.parse("(1)()");
  91:     x.initialize(new DefaultFormulaContext());
  92:     System.out.println(x);
  93:   }
  94: }