ingo@369: package de.intevation.flys.exports;
ingo@369: 
ingo@369: import java.awt.Color;
ingo@369: 
ingo@369: import java.io.IOException;
ingo@369: 
ingo@369: import org.apache.log4j.Logger;
ingo@369: 
ingo@369: import org.jfree.chart.ChartFactory;
ingo@369: import org.jfree.chart.JFreeChart;
ingo@369: import org.jfree.chart.axis.NumberAxis;
ingo@369: import org.jfree.chart.plot.PlotOrientation;
ingo@369: import org.jfree.chart.plot.XYPlot;
ingo@369: 
ingo@369: import de.intevation.flys.exports.ChartExportHelper;
ingo@369: 
ingo@369: 
ingo@369: /**
ingo@369:  * An abstract base class for creating XY charts.
ingo@369:  *
ingo@369:  * @author <a href="mailto:ingo.weinzierl@intevation.de">Ingo Weinzierl</a>
ingo@369:  */
ingo@369: public abstract class XYChartGenerator extends ChartGenerator {
ingo@369: 
ingo@369:     /** The logger that is used in this generator.*/
ingo@369:     private static Logger logger = Logger.getLogger(ChartGenerator.class);
ingo@369: 
ingo@369: 
ingo@369:     /**
ingo@369:      * Returns the title of a chart.
ingo@369:      *
ingo@369:      * @return the title of a chart.
ingo@369:      */
ingo@369:     protected abstract String getChartTitle();
ingo@369: 
ingo@369:     /**
ingo@369:      * Returns the X-Axis label of a chart.
ingo@369:      *
ingo@369:      * @return the X-Axis label of a chart.
ingo@369:      */
ingo@369:     protected abstract String getXAxisLabel();
ingo@369: 
ingo@369:     /**
ingo@369:      * Returns the Y-Axis label of a chart.
ingo@369:      *
ingo@369:      * @return the Y-Axis label of a chart.
ingo@369:      */
ingo@369:     protected abstract String getYAxisLabel();
ingo@369: 
ingo@369:     /**
ingo@375:      * This method is called to add all datasets of a concrete XYChartGenerator
ingo@375:      * to the JFreeChart.
ingo@369:      *
ingo@375:      * @param chart The JFreeChart object.
ingo@369:      */
ingo@375:     protected abstract void addDatasets(JFreeChart chart);
ingo@369: 
ingo@369: 
ingo@369:     public void generate()
ingo@369:     throws IOException
ingo@369:     {
ingo@369:         logger.debug("XYChartGenerator.generate");
ingo@369: 
ingo@369:         JFreeChart chart = ChartFactory.createXYLineChart(
ingo@369:             getChartTitle(),
ingo@369:             getXAxisLabel(),
ingo@369:             getYAxisLabel(),
ingo@375:             null,
ingo@369:             PlotOrientation.VERTICAL,
ingo@369:             true,
ingo@369:             false,
ingo@369:             false);
ingo@369: 
ingo@369:         chart.setBackgroundPaint(Color.WHITE);
ingo@369:         chart.getPlot().setBackgroundPaint(Color.WHITE);
ingo@369: 
ingo@375:         addDatasets(chart);
ingo@414:         addSubtitles(chart);
ingo@369:         adjustAxes((XYPlot) chart.getPlot());
ingo@369: 
ingo@369:         ChartExportHelper.exportImage(
ingo@369:             out,
ingo@369:             chart,
ingo@369:             "png",
ingo@369:             600, 400);
ingo@369:     }
ingo@369: 
ingo@369: 
ingo@369:     /**
ingo@369:      * Adjusts the axes of a plot.
ingo@369:      *
ingo@369:      * @param plot The XYPlot of the chart.
ingo@369:      */
ingo@369:     protected void adjustAxes(XYPlot plot) {
ingo@369:         NumberAxis yAxis = (NumberAxis) plot.getRangeAxis();
ingo@369: 
ingo@369:         yAxis.setAutoRangeIncludesZero(false);
ingo@369:     }
ingo@414: 
ingo@414: 
ingo@414:     protected void addSubtitles(JFreeChart chart) {
ingo@414:         // override this method in subclasses that need subtitles
ingo@414:     }
ingo@369: }
ingo@369: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :