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: NotEqualOperator.java 3521 2007-10-16 10:55:14Z tmorgner $ 028 * ------------ 029 * (C) Copyright 2006-2007, by Pentaho Corporation. 030 */ 031 package org.jfree.formula.operators; 032 033 import org.jfree.formula.lvalues.TypeValuePair; 034 import org.jfree.formula.EvaluationException; 035 import org.jfree.formula.FormulaContext; 036 import org.jfree.formula.typing.TypeRegistry; 037 import org.jfree.formula.typing.ExtendedComparator; 038 import org.jfree.formula.typing.coretypes.LogicalType; 039 040 /** 041 * Creation-Date: 31.10.2006, 16:34:11 042 * 043 * @author Thomas Morgner 044 */ 045 public class NotEqualOperator implements InfixOperator 046 { 047 private static final TypeValuePair RETURN_TRUE = new TypeValuePair(LogicalType.TYPE, Boolean.TRUE); 048 private static final TypeValuePair RETURN_FALSE = new TypeValuePair(LogicalType.TYPE, Boolean.FALSE); 049 050 public NotEqualOperator() 051 { 052 } 053 054 public TypeValuePair evaluate(final FormulaContext context, 055 final TypeValuePair value1, final TypeValuePair value2) 056 throws EvaluationException 057 { 058 final TypeRegistry typeRegistry = context.getTypeRegistry(); 059 060 final ExtendedComparator comparator = 061 typeRegistry.getComparator(value1.getType(), value2.getType()); 062 final boolean result = comparator.isEqual 063 (value1.getType(), value1.getValue(), 064 value2.getType(), value2.getValue()); 065 066 if (result == false) 067 { 068 return RETURN_TRUE; 069 } 070 else 071 { 072 return RETURN_FALSE; 073 } 074 } 075 076 public int getLevel() 077 { 078 return 400; 079 } 080 081 public String toString() 082 { 083 return "<>"; 084 } 085 086 /** 087 * Defines the bind-direction of the operator. That direction defines, in 088 * which direction a sequence of equal operators is resolved. 089 * 090 * @return true, if the operation is left-binding, false if right-binding 091 */ 092 public boolean isLeftOperation() 093 { 094 return true; 095 } 096 097 /** 098 * Defines, whether the operation is associative. For associative operations, 099 * 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 }