001/*
002 * $Id$
003 *
004 * Copyright 2009 Sun Microsystems, Inc., 4150 Network Circle,
005 * Santa Clara, California 95054, U.S.A. All rights reserved.
006 *
007 * This library is free software; you can redistribute it and/or
008 * modify it under the terms of the GNU Lesser General Public
009 * License as published by the Free Software Foundation; either
010 * version 2.1 of the License, or (at your option) any later version.
011 * 
012 * This library is distributed in the hope that it will be useful,
013 * but WITHOUT ANY WARRANTY; without even the implied warranty of
014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
015 * Lesser General Public License for more details.
016 * 
017 * You should have received a copy of the GNU Lesser General Public
018 * License along with this library; if not, write to the Free Software
019 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
020 *
021 */
022package org.jdesktop.swingx.text;
023
024import java.text.AttributedCharacterIterator;
025import java.text.AttributedString;
026import java.text.FieldPosition;
027import java.text.NumberFormat;
028import java.text.ParsePosition;
029
030/**
031 * A specialised NumberFormat which handles null values and empty Strings. 
032 * This is useful in cell editors and used in StrictNumberFormatter.
033 * 
034 * @author Noel Grandin
035 * @author Jeanette Winzenburg
036 */
037public class NumberFormatExt extends NumberFormat {
038    
039    private NumberFormat childFormat;
040
041    public NumberFormatExt() {
042        this(null);
043    }
044    
045    public NumberFormatExt(NumberFormat childFormat) {
046        if (childFormat == null) {
047            childFormat = NumberFormat.getInstance();
048        }
049        this.childFormat = childFormat;
050    }
051
052    @Override
053    public AttributedCharacterIterator formatToCharacterIterator(Object obj) {
054        if (obj == null)
055            return new AttributedString("").getIterator();
056        return childFormat.formatToCharacterIterator(obj);
057    }
058
059    @Override
060    public StringBuffer format(Object obj, StringBuffer toAppendTo,
061            FieldPosition pos) {
062        if (obj == null)
063            return new StringBuffer("");
064        return childFormat.format(obj, toAppendTo, pos);
065    }
066
067    @Override
068    public Number parse(String source, ParsePosition pos) {
069        if (source == null) {
070            pos.setIndex(1); // otherwise Format thinks parse failed
071            return null;
072        }
073        if (source.trim().equals("")) {
074            pos.setIndex(1); // otherwise Format thinks parse failed
075            return null;
076        }
077        Number val = childFormat.parse(source, pos);
078        /*
079         * The default behaviour of Format objects is to keep parsing as long as
080         * they encounter valid data. By for table editing we don't want
081         * trailing bad data to be considered a "valid value". So set the index
082         * to 0 so that the parse(Object) method knows that we had an error.
083         */
084        if (pos.getIndex() != source.length()) {
085            pos.setErrorIndex(pos.getIndex());
086            pos.setIndex(0);
087        }
088        return val;
089    }
090
091    @Override
092    public StringBuffer format(double number, StringBuffer toAppendTo,
093            FieldPosition pos) {
094        return childFormat.format(number, toAppendTo, pos);
095    }
096
097    @Override
098    public StringBuffer format(long number, StringBuffer toAppendTo,
099            FieldPosition pos) {
100        return childFormat.format(number, toAppendTo, pos);
101    }
102
103}