edu.cudenver.bios.chartsvc.representation.LegendImageRepresentation.java Source code

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Here is the source code for edu.cudenver.bios.chartsvc.representation.LegendImageRepresentation.java

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/*
 * Chart Service for the GLIMMPSE Software System.  Creates
 * publishable quality scatter plots.
 * 
 * Copyright (C) 2010 Regents of the University of Colorado.  
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
package edu.cudenver.bios.chartsvc.representation;

import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.geom.Rectangle2D;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream;

import org.jfree.chart.block.BlockBorder;
import org.jfree.chart.block.ColumnArrangement;
import org.jfree.chart.block.RectangleConstraint;
import org.jfree.chart.encoders.EncoderUtil;
import org.jfree.chart.encoders.ImageFormat;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.title.LegendTitle;
import org.jfree.ui.RectangleEdge;
import org.restlet.data.MediaType;
import org.restlet.representation.OutputRepresentation;

/**
 * Class to create a JPEG image representation of the chart legend
 * @author Sarah Kreidler
 *
 */
public class LegendImageRepresentation extends OutputRepresentation {
    //protected JFreeChart plot;
    protected XYPlot plot;
    protected int width, height;

    /**
     * Create a JPEG image representation of the chart legend
     * @param chart chart object
     * @param width width of the output JPEG
     * @param height height of the output JPEG
     */
    public LegendImageRepresentation(XYPlot plot, int width, int height) {
        super(MediaType.IMAGE_JPEG);
        this.plot = plot;
        this.width = width;
        this.height = height;

    }

    /**
     * Called internally by Restlet library to write the image as the HTTP
     * response.
     * @param out output stream
     */
    @Override
    public void write(OutputStream out) throws IOException {
        // build the legend from the plot, and write it to a jpeg image
        if (plot != null) {
            LegendTitle legend = new LegendTitle(plot, new ColumnArrangement(), new ColumnArrangement());
            legend.setFrame(BlockBorder.NONE);
            //legend.setMargin(new RectangleInsets(2.0, 2.0, 2.0, 2.0));
            legend.setBackgroundPaint(Color.white);
            legend.setPosition(RectangleEdge.BOTTOM);
            BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
            Graphics2D g = image.createGraphics();
            Rectangle2D.Double legendArea = new Rectangle2D.Double(0, 0, width, height);
            g.clip(legendArea);
            legend.arrange(g, new RectangleConstraint(width, height));
            legend.draw(g, legendArea);
            g.dispose();
            EncoderUtil.writeBufferedImage(image, ImageFormat.JPEG, out);
        }
    }

}