peakml.graphics.JFreeChartTools.java Source code

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Here is the source code for peakml.graphics.JFreeChartTools.java

Source

/* Copyright (C) 2008, Groningen Bioinformatics Centre (http://gbic.biol.rug.nl/)
 * This file is part of mzMatch.
 * 
 * PeakML is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or
 * (at your option) any later version.
 * 
 * mzMatch is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public License
 * along with PeakML; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

package peakml.graphics;

// java
import java.io.*;
import java.awt.image.*;

// itext
import com.lowagie.text.*;
import com.lowagie.text.pdf.*;

// jfreechart
import org.jfree.chart.*;

/**
 * This class offers an interface for dealing with JFreeChart graphs. Most notably
 * methods are provided for exporting the graphs to files.
 */
public class JFreeChartTools {
    /** Write in the PDF format, which has the graphics in vector format. */
    public static final int PDF = 0;
    /** Write in the PNG format, which is pixel-based but readable anywhere. */
    public static final int PNG = 1;

    // chart write functions
    /**
     * General access method, which can be plugged with the filetype to write to. This
     * method links through to {@link JFreeChartTools#writeAsPDF(OutputStream, JFreeChart, int, int)}
     * and {@link JFreeChartTools#writeAsPNG(OutputStream, JFreeChart, int, int)}.
     * 
     * @param filetype      The type of file to write.
     * @param out         The output stream to write to.
     * @param chart         The chart to be written.
     * @param width         The width of the image.
     * @param height      The height of the image.
     * @throws IOException   Thrown when an error occurs with the IO.
     */
    public static void writeAs(int filetype, OutputStream out, JFreeChart chart, int width, int height)
            throws IOException {
        if (filetype == PDF)
            writeAsPDF(out, chart, width, height);
        else if (filetype == PNG)
            writeAsPNG(out, chart, width, height);
        else
            throw new IOException("Unknown file format.");
    }

    /**
     * This method writes the given graph to the output stream in the PDF format. As a vector
     * based file format it allows some freedom to be changed (e.g. colors, line thickness, etc.),
     * which can be convenient for presentation purposes.
     * 
     * @param out         The output stream to write to.
     * @param chart         The chart to be written.
     * @param width         The width of the image.
     * @param height      The height of the image.
     * @throws IOException   Thrown when an error occurs with the IO.
     */
    public static void writeAsPDF(OutputStream out, JFreeChart chart, int width, int height) throws IOException {
        Document document = new Document(new Rectangle(width, height), 50, 50, 50, 50);
        document.addAuthor("");
        document.addSubject("");

        try {
            PdfWriter writer = PdfWriter.getInstance(document, out);
            document.open();
            PdfContentByte cb = writer.getDirectContent();
            PdfTemplate tp = cb.createTemplate(width, height);

            java.awt.Graphics2D g2 = tp.createGraphics(width, height, new DefaultFontMapper());
            chart.draw(g2, new java.awt.geom.Rectangle2D.Double(0, 0, width, height));

            g2.dispose();
            cb.addTemplate(tp, 0, 0);
        } catch (DocumentException de) {
            throw new IOException(de.getMessage());
        }

        document.close();
    }

    /**
     * This method writes the given graph to the output stream in the PNG format.
     * 
     * @param out         The output stream to write to.
     * @param chart         The chart to be written.
     * @param width         The width of the image.
     * @param height      The height of the image.
     * @throws IOException   Thrown when an error occurs with the IO.
     */
    public static void writeAsPNG(OutputStream out, JFreeChart chart, int width, int height) throws IOException {
        BufferedImage graph_img = new BufferedImage(800, 500, BufferedImage.TYPE_INT_ARGB);
        chart.draw(graph_img.createGraphics(), new java.awt.Rectangle(0, 0, 800, 500));
        javax.imageio.ImageIO.write(graph_img, "png", out);
    }
}