001/* ========================================================================
002 * JCommon : a free general purpose class library for the Java(tm) platform
003 * ========================================================================
004 *
005 * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
006 * 
007 * Project Info:  http://www.jfree.org/jcommon/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it 
010 * under the terms of the GNU Lesser General Public License as published by 
011 * the Free Software Foundation; either version 2.1 of the License, or 
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but 
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
022 * USA.  
023 *
024 * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
025 * in the United States and other countries.]
026 * 
027 * -------------------
028 * G2TextMeasurer.java
029 * -------------------
030 * (C) Copyright 2004, 2005, by Object Refinery Limited and Contributors.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   -;
034 *
035 * $Id: G2TextMeasurer.java,v 1.4 2005/10/18 13:17:16 mungady Exp $
036 *
037 * Changes
038 * -------
039 * 07-Jan-2004 : Version 1 (DG);
040 *
041 */
042 
043package org.jfree.text;
044
045import java.awt.FontMetrics;
046import java.awt.Graphics2D;
047import java.awt.geom.Rectangle2D;
048
049/**
050 * A {@link TextMeasurer} based on a {@link Graphics2D}.
051 *
052 * @author David Gilbert
053 */
054public class G2TextMeasurer implements TextMeasurer {
055
056    /** The graphics device. */
057    private Graphics2D g2;
058    
059    /**
060     * Creates a new text measurer.
061     * 
062     * @param g2  the graphics device.
063     */
064    public G2TextMeasurer(final Graphics2D g2) {
065        this.g2 = g2;
066    }
067
068    /**
069     * Returns the string width.
070     * 
071     * @param text  the text.
072     * @param start  the index of the first character to measure.
073     * @param end  the index of the last character to measure.
074     * 
075     * @return The string width.
076     */
077    public float getStringWidth(final String text, 
078                                final int start, final int end) {
079        final FontMetrics fm = this.g2.getFontMetrics();
080        final Rectangle2D bounds = TextUtilities.getTextBounds(
081            text.substring(start, end), this.g2, fm
082        );
083        final float result = (float) bounds.getWidth();
084        return result;
085    }
086    
087}
088