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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: NotEqualOperator.java,v 1.6 2007/04/01 13:51:54 taqua Exp $ 28: * ------------ 29: * (C) Copyright 2006-2007, by Pentaho Corporation. 30: */ 31: package org.jfree.formula.operators; 32: 33: import org.jfree.formula.lvalues.TypeValuePair; 34: import org.jfree.formula.EvaluationException; 35: import org.jfree.formula.FormulaContext; 36: import org.jfree.formula.typing.TypeRegistry; 37: import org.jfree.formula.typing.ExtendedComparator; 38: import org.jfree.formula.typing.coretypes.LogicalType; 39: 40: /** 41: * Creation-Date: 31.10.2006, 16:34:11 42: * 43: * @author Thomas Morgner 44: */ 45: public class NotEqualOperator implements InfixOperator 46: { 47: private static final TypeValuePair RETURN_TRUE = new TypeValuePair(LogicalType.TYPE, Boolean.TRUE); 48: private static final TypeValuePair RETURN_FALSE = new TypeValuePair(LogicalType.TYPE, Boolean.FALSE); 49: 50: public NotEqualOperator() 51: { 52: } 53: 54: public TypeValuePair evaluate(final FormulaContext context, 55: TypeValuePair value1, TypeValuePair value2) 56: throws EvaluationException 57: { 58: final TypeRegistry typeRegistry = context.getTypeRegistry(); 59: 60: final ExtendedComparator comparator = 61: typeRegistry.getComparator(value1.getType(), value2.getType()); 62: final boolean result = comparator.isEqual 63: (value1.getType(), value1.getValue(), 64: value2.getType(), value2.getValue()); 65: 66: if (result == false) 67: { 68: return RETURN_TRUE; 69: } 70: else 71: { 72: return RETURN_FALSE; 73: } 74: } 75: 76: public int getLevel() 77: { 78: return 400; 79: } 80: 81: public String toString() 82: { 83: return "<>"; 84: } 85: 86: /** 87: * Defines the bind-direction of the operator. That direction defines, in 88: * which direction a sequence of equal operators is resolved. 89: * 90: * @return true, if the operation is left-binding, false if right-binding 91: */ 92: public boolean isLeftOperation() 93: { 94: return true; 95: } 96: 97: /** 98: * Defines, whether the operation is associative. For associative operations, 99: * the evaluation order does not matter, if the operation appears more than 100: * once in an expression, and therefore we can optimize them a lot better than 101: * non-associative operations (ie. merge constant parts and precompute them 102: * once). 103: * 104: * @return true, if the operation is associative, false otherwise 105: */ 106: public boolean isAssociative() 107: { 108: return false; 109: } 110: 111: }