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    }