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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: Formula.java 3515 2007-10-16 09:22:24Z tmorgner $ 28: * ------------ 29: * (C) Copyright 2006-2007, by Pentaho Corporation. 30: */ 31: package org.jfree.formula; 32: 33: import java.io.Serializable; 34: 35: import org.jfree.formula.lvalues.LValue; 36: import org.jfree.formula.lvalues.TypeValuePair; 37: import org.jfree.formula.parser.FormulaParser; 38: import org.jfree.formula.parser.ParseException; 39: import org.jfree.formula.parser.TokenMgrError; 40: import org.jfree.formula.typing.Type; 41: import org.jfree.formula.typing.coretypes.ErrorType; 42: import org.jfree.util.Log; 43: 44: /** 45: * Creation-Date: 31.10.2006, 14:43:05 46: * 47: * @author Thomas Morgner 48: */ 49: public class Formula implements Serializable, Cloneable 50: { 51: private LValue rootReference; 52: 53: public Formula(final String formulaText) throws ParseException 54: { 55: try 56: { 57: final FormulaParser parser = new FormulaParser(); 58: this.rootReference = parser.parse(formulaText); 59: } 60: catch(TokenMgrError tokenMgrError) 61: { 62: // This is ugly. 63: throw new ParseException(tokenMgrError.getMessage()); 64: } 65: } 66: 67: public Formula(final LValue rootReference) 68: { 69: this.rootReference = rootReference; 70: } 71: 72: public void initialize (final FormulaContext context) throws EvaluationException 73: { 74: rootReference.initialize(context); 75: } 76: 77: /** 78: * Returns the root reference for this formula. This allows external programms 79: * to modify the formula directly. 80: * 81: * @return 82: */ 83: public LValue getRootReference() 84: { 85: return rootReference; 86: } 87: 88: public TypeValuePair evaluateTyped () 89: { 90: try 91: { 92: final TypeValuePair typeValuePair = rootReference.evaluate(); 93: if (typeValuePair == null) 94: { 95: // Should no longer happen.. 96: return new TypeValuePair 97: (ErrorType.TYPE, LibFormulaErrorValue.ERROR_NA_VALUE); 98: } 99: if(typeValuePair.getType().isFlagSet(Type.ERROR_TYPE)) 100: { 101: Log.debug ("Error: " + typeValuePair.getValue()); 102: } 103: return typeValuePair; 104: } 105: catch(EvaluationException ee) 106: { 107: return new TypeValuePair(ErrorType.TYPE, ee.getErrorValue()); 108: } 109: catch (Exception e) 110: { 111: Log.warn ("Evaluation failed unexpectedly: ", e); 112: return new TypeValuePair(ErrorType.TYPE, LibFormulaErrorValue.ERROR_UNEXPECTED_VALUE); 113: } 114: } 115: 116: public Object evaluate () 117: { 118: return evaluateTyped().getValue(); 119: } 120: 121: public Object clone () throws CloneNotSupportedException 122: { 123: final Formula o = (Formula) super.clone(); 124: o.rootReference = (LValue) rootReference.clone(); 125: return o; 126: } 127: }