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: PostfixTerm.java 2716 2007-04-01 13:51:58Z taqua $
028 * ------------
029 * (C) Copyright 2006-2007, by Pentaho Corporation.
030 */
031 package org.jfree.formula.lvalues;
032
033 import org.jfree.formula.EvaluationException;
034 import org.jfree.formula.operators.PostfixOperator;
035
036 /**
037 * Creation-Date: 02.11.2006, 10:20:27
038 *
039 * @author Thomas Morgner
040 */
041 public class PostfixTerm extends AbstractLValue
042 {
043 private PostfixOperator operator;
044 private LValue value;
045
046 public PostfixTerm(final LValue value, final PostfixOperator operator)
047 {
048 if (operator == null)
049 {
050 throw new NullPointerException();
051 }
052 if (value == null)
053 {
054 throw new NullPointerException();
055 }
056 this.operator = operator;
057 this.value = value;
058 }
059
060 public PostfixOperator getOperator()
061 {
062 return operator;
063 }
064
065 public LValue getValue()
066 {
067 return value;
068 }
069
070 public TypeValuePair evaluate() throws EvaluationException
071 {
072 return operator.evaluate(getContext(), value.evaluate());
073 }
074
075
076 public String toString()
077 {
078 return "(" + value + operator + ')';
079 }
080
081 /**
082 * Checks, whether the LValue is constant. Constant lvalues always return the
083 * same value.
084 *
085 * @return
086 */
087 public boolean isConstant()
088 {
089 return value.isConstant();
090 }
091
092 /**
093 * Returns any dependent lvalues (parameters and operands, mostly).
094 *
095 * @return
096 */
097 public LValue[] getChildValues()
098 {
099 return new LValue[]{ value };
100 }
101
102 public Object clone() throws CloneNotSupportedException
103 {
104 final PostfixTerm o = (PostfixTerm) super.clone();
105 o.value = (LValue) value.clone();
106 return o;
107 }
108 }