/*
* Copyright (C) 2010-2012 Stichting Akvo (Akvo Foundation)
*
* This file is part of Akvo FLOW.
*
* Akvo FLOW is free software: you can redistribute it and modify it under the terms of
* the GNU Affero General Public License (AGPL) as published by the Free Software Foundation,
* either version 3 of the License or any later version.
*
* Akvo FLOW 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 Affero General Public License included below for more details.
*
* The full license text can also be seen at <http://www.gnu.org/licenses/agpl.html>.
*/
package com.gallatinsystems.common.util;
import java.util.List;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartUtilities;
import org.jfree.chart.JFreeChart;
import org.jfree.data.general.DefaultPieDataset;
/**
* wrapper class for interaction with the JFreechart library.
*
* @author cfagiani
*/
public class JFreechartChartUtil {
/**
* generates a pie chart with the set of labels and values passed in (the labels and values
* arrays must both be non-null and contain the same number of elements). The chart is returned
* as a byte array representing the image.
*
* @param labels
* @param values
* @param title
* @param width
* @param height
* @return - byte array containing the image, null if there is an error.
*/
public static byte[] getPieChart(List<String> labels, List<String> values,
String title, int width, int height) {
DefaultPieDataset pieDataset = new DefaultPieDataset();
for (int i = 0; i < labels.size(); i++) {
pieDataset.setValue(labels.get(i) + " (" + values.get(i) + ")",
Double.parseDouble(values.get(i)));
}
JFreeChart chart = ChartFactory.createPieChart(title, pieDataset,
false, false, false);
try {
return ChartUtilities.encodeAsPNG(chart.createBufferedImage(width,
height));
} catch (Exception e) {
e.printStackTrace(System.err);
return null;
}
}
}