Source for org.jfree.formula.lvalues.StaticValue

   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: StaticValue.java,v 1.7 2007/05/15 23:28:41 willgorman Exp $
  28:  * ------------
  29:  * (C) Copyright 2006-2007, by Pentaho Corporation.
  30:  */
  31: package org.jfree.formula.lvalues;
  32: 
  33: import org.jfree.formula.EvaluationException;
  34: import org.jfree.formula.FormulaContext;
  35: import org.jfree.formula.typing.Type;
  36: import org.jfree.formula.typing.coretypes.AnyType;
  37: 
  38: /**
  39:  * Creation-Date: 08.10.2006, 11:34:40
  40:  *
  41:  * @author Thomas Morgner
  42:  */
  43: public class StaticValue extends AbstractLValue
  44: {
  45:   private Object value;
  46:   private Type type;
  47: 
  48:   public StaticValue(final Object value)
  49:   {
  50:     this(value, AnyType.TYPE);
  51:   }
  52:   
  53:   public StaticValue(final Object value, Type type)
  54:   {
  55:     this.value = value;
  56:     this.type = type;
  57:   }
  58: 
  59:   public void initialize(FormulaContext context) throws EvaluationException
  60:   {
  61:   }
  62: 
  63:   public TypeValuePair evaluate()
  64:   {
  65:     return new TypeValuePair(type, value);
  66:   }
  67: 
  68: 
  69:   public String toString()
  70:   {
  71:     return String.valueOf(value);
  72:   }
  73: 
  74:   /**
  75:    * Checks, whether the LValue is constant. Constant lvalues always return the
  76:    * same value.
  77:    *
  78:    * @return
  79:    */
  80:   public boolean isConstant()
  81:   {
  82:     return true;
  83:   }
  84: 
  85:   public Object getValue()
  86:   {
  87:     return value;
  88:   }
  89: 
  90:   /**
  91:    * This function allows a program traversing the LibFormula object model
  92:    * to know what type this static value is.
  93:    *
  94:    * @return the type of the static value
  95:    *
  96:    */ 
  97:   public Type getValueType()
  98:   {
  99:     return type;
 100:   }
 101: }