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: TrueFunctionDescription.java 3521 2007-10-16 10:55:14Z tmorgner $
028 * ------------
029 * (C) Copyright 2006-2007, by Pentaho Corporation.
030 */
031 package org.jfree.formula.function.logical;
032
033 import org.jfree.formula.function.AbstractFunctionDescription;
034 import org.jfree.formula.function.FunctionCategory;
035 import org.jfree.formula.typing.Type;
036 import org.jfree.formula.typing.coretypes.LogicalType;
037
038 /**
039 * Creation-Date: 04.11.2006, 18:28:55
040 *
041 * @author Thomas Morgner
042 */
043 public class TrueFunctionDescription extends AbstractFunctionDescription
044 {
045 public TrueFunctionDescription()
046 {
047 super("org.jfree.formula.function.logical.True-Function");
048 }
049
050 public int getParameterCount()
051 {
052 return 0;
053 }
054
055 public boolean isInfiniteParameterCount()
056 {
057 return false;
058 }
059
060 public Type getParameterType(final int position)
061 {
062 return LogicalType.TYPE;
063 }
064
065 public Type getValueType()
066 {
067 return LogicalType.TYPE;
068 }
069
070 /**
071 * Defines, whether the parameter at the given position is mandatory. A
072 * mandatory parameter must be filled in, while optional parameters need not
073 * to be filled in.
074 *
075 * @return
076 */
077 public boolean isParameterMandatory(final int position)
078 {
079 return false;
080 }
081
082 /**
083 * Returns the default value for an optional parameter. If the value returned
084 * here is null, then this either means, that the parameter is mandatory or
085 * that the default value is computed by the expression itself.
086 *
087 * @param position
088 * @return
089 */
090 public Object getDefaultValue(final int position)
091 {
092 return null;
093 }
094
095 public FunctionCategory getCategory()
096 {
097 return LogicalFunctionCategory.CATEGORY;
098 }
099
100 }