lab/src/main/java/net/engio/pips/reports/ChartGenerator.java

package net.engio.pips.reports;

import net.engio.pips.lab.Benchmark;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartUtilities;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.AxisLocation;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYLineAndShapeRenderer;
import org.jfree.data.time.TimeSeriesCollection;

import java.awt.*;
import java.io.File;
import java.io.IOException;
import java.util.*;
import java.util.List;

/**
 *
 * @author bennidi
 *         Date: 3/3/14
 */
public class ChartGenerator implements IReporter {

    private List<SeriesGroup> groups = new ArrayList<SeriesGroup>();
    private int pixelPerDatapoint = 5;
    private String title = "Title";
    private String xLabel = "X-Axis";
    private String filename = "chart.jpg";

    public ChartGenerator setPixelPerDatapoint(int pxPerDP) {
        this.pixelPerDatapoint = pxPerDP;
        return this;
    }

    public ChartGenerator setTitle(String title) {
        this.title = title;
        return this;
    }

    public ChartGenerator setXAxisLabel(String xLabel) {
        this.xLabel = xLabel;
        return this;
    }

    public ChartGenerator setFileName(String filename){
        this.filename = filename;
        return this;
    }


    public ChartGenerator draw(SeriesGroup seriesGroup) {
        groups.add(seriesGroup);
        return this;
    }

    public void generate(Benchmark benchmark){
        Map<String, Integer> groupAxis = new HashMap<String, Integer>();
        // process default group
        SeriesGroup defaultGroup = this.groups.get(0);
        TimeSeriesCollection collection = defaultGroup.createDataSet(benchmark);
        int maxNumberOfDatapoints = defaultGroup.getSize();
        groupAxis.put(defaultGroup.getLabel(), 0);

        // create initial chart
        JFreeChart chart = ChartFactory.createTimeSeriesChart(
                title,  // title
                xLabel,             // x-axis label
                defaultGroup.getLabel(),   // y-axis label
                collection,            // data
                true,               // create legend?
                true,               // generate tooltips?
                false               // generate URLs?
        );

        // preconfigure plot layout
        final XYPlot plot = chart.getXYPlot();
        plot.setRangeGridlinesVisible(true);
        plot.setRangeGridlinePaint(Color.BLACK);
        plot.setDomainGridlinesVisible(true);
        plot.setDomainGridlinePaint(Color.BLACK);
        plot.setBackgroundPaint(Color.DARK_GRAY);
        plot.setRenderer(0, getRandomRenderer());
        // add other groups
        List<SeriesGroup> groups = this.groups.subList(1, this.groups.size());
        int axisIndex = 1,
            dataSetIndex = 1;
        for(SeriesGroup group : groups){
            plot.setDataset(dataSetIndex, group.createDataSet(benchmark));
            plot.setRenderer(dataSetIndex, getRandomRenderer());

            // if the group does not share a range axis with an already mapped group
            if(!groupAxis.containsKey(group.getLabel())){
                final NumberAxis axis2 = new NumberAxis(group.getLabel());
                // prevent the axis to be scaled from zero if the dataset begins with higher values
                axis2.setAutoRangeIncludesZero(true);
                plot.setRangeAxis(axisIndex, axis2);
                plot.mapDatasetToRangeAxis(dataSetIndex, axisIndex);
                plot.setRangeAxisLocation(axisIndex, group.getOrientation() == SeriesGroup.Orientation.Left
                        ? AxisLocation.BOTTOM_OR_LEFT
                        : AxisLocation.BOTTOM_OR_RIGHT);
                groupAxis.put(group.getLabel(), axisIndex); // remember this axis for subsequent groups
                axisIndex++;
            }
            else{
                plot.mapDatasetToRangeAxis(dataSetIndex, groupAxis.get(group.getLabel()));
            }

            dataSetIndex++;
           if(maxNumberOfDatapoints < group.getSize())maxNumberOfDatapoints = group.getSize();
        }

        // calculate width of graph based on number of total data points
        // Note: assumes that the data of all groups spans (roughly) the same domain range
        int width = maxNumberOfDatapoints * pixelPerDatapoint;

        try {
            String path = benchmark.getReportBaseDir() + filename;
            ChartUtilities.saveChartAsJPEG(new File(path), chart, width <= 1024 ? 1024 : width, 1024);
        } catch (IOException e) {
            System.err.println("Problem occurred creating chart.");
        }
    }

    private Random rand = new Random();
    private Color getRandomColor(){
        return new Color(Math.abs(rand.nextInt()) % 256,// r
                Math.abs(rand.nextInt()) % 256, // g
                Math.abs(rand.nextInt()) % 256); //b
    }


    private XYLineAndShapeRenderer getRandomRenderer(){
        XYLineAndShapeRenderer renderer = new XYLineAndShapeRenderer();
        renderer.setSeriesPaint(0, getRandomColor());
        return renderer;
    }

}