ingo@1115: /* ingo@1115: * Copyright (c) 2010 by Intevation GmbH ingo@1115: * ingo@1115: * This program is free software under the LGPL (>=v2.1) ingo@1115: * Read the file LGPL.txt coming with the software for details ingo@1115: * or visit http://www.gnu.org/licenses/ if it does not exist. ingo@1115: */ ingo@1115: ingo@617: package de.intevation.gnv.chart; ingo@617: ingo@1107: import java.util.Locale; ingo@629: import java.util.Map; ingo@629: ingo@617: import org.apache.log4j.Logger; ingo@617: ingo@617: import org.jfree.chart.ChartTheme; sascha@623: ingo@617: import org.jfree.chart.plot.XYPlot; ingo@617: ingo@617: /** ingo@767: * Default implementation of {@link de.intevation.gnv.chart.AbstractHistogram}. ingo@767: * ingo@767: * @author Ingo Weinzierl ingo@617: */ ingo@617: public class DefaultHistogram ingo@617: extends AbstractHistogram ingo@617: { ingo@767: /** ingo@767: * Default bin count. ingo@767: * TODO find a better default value ingo@767: */ ingo@617: public static final int DEFAULT_BINS = 15; ingo@767: ingo@767: /** ingo@767: * Constant field for limitating the number of bin in a single histogram. ingo@767: */ ingo@629: public static final int MAXIMAL_BINS = 20; ingo@767: ingo@767: /** ingo@767: * Default key to retrieve the number of bins from {@link ingo@767: * #requestParameter}. ingo@767: */ ingo@629: public static final String REQUEST_KEY_BIN_COUNT = "bincount"; ingo@767: ingo@767: /** ingo@767: * Default key to retrieve the width of a single bin from {@link ingo@767: * #requestParameter}. ingo@767: */ ingo@629: public static final String REQUEST_KEY_BIN_WIDTH = "binwidth"; ingo@767: ingo@767: /** ingo@767: * Default key to retrieve the chart width from {@link #requestParameter}. ingo@767: */ ingo@629: public static final String REQUEST_KEY_CHART_WIDTH = "width"; ingo@767: ingo@767: /** sascha@778: * Default key to retrieve the object from {@link #requestParameter}. It ingo@767: * defines which value this chart has to be used for bin calculation. You ingo@767: * can either adjust the number of bins or the width of a single bin. ingo@767: */ ingo@629: public static final String REQUEST_KEY_BIN_CHOICE = "bintype"; ingo@617: ingo@767: /** ingo@767: * Logger used for logging with log4j. ingo@767: */ ingo@617: private static Logger logger = Logger.getLogger(DefaultHistogram.class); ingo@617: ingo@767: /** ingo@767: * Object storing some further parameter used for chart settings. ingo@767: */ ingo@629: protected Map requestParameter; ingo@629: ingo@1055: protected double[] minmax = null; ingo@1055: ingo@617: ingo@767: /** ingo@767: * Constructor to create DefaultHistogram objects. ingo@767: * ingo@767: * @param labels Labels to decorate this chart. ingo@767: * @param data Raw data to be displayed in histogram. ingo@767: * @param theme Theme used to adjust the chart look. ingo@767: * @param requestParameter Object which serves some further settings. ingo@767: */ ingo@617: public DefaultHistogram( ingo@629: ChartLabels labels, Object[] data, ChartTheme theme, Map requestParameter ingo@617: ) { ingo@617: super(labels, data, theme); ingo@629: this.requestParameter = requestParameter; ingo@1107: this.locale = (Locale) requestParameter.get("locale"); ingo@617: } ingo@617: ingo@617: ingo@767: @Override ingo@617: protected void applyDatasets() { ingo@617: XYPlot plot = (XYPlot) chart.getPlot(); ingo@617: ingo@617: // prepare data and create add them to histogram dataset ingo@617: String name = (String) data[0]; ingo@617: double[] values = toDouble((Double[]) data[1]); ingo@617: ingo@1055: double binWidth = getBinWidth(values); ingo@1055: int binCount = getBinCount(); ingo@1055: ingo@1055: AdvancedHistogramDataset dataset = ingo@1055: new AdvancedHistogramDataset(binCount, binWidth); ingo@1055: dataset.addSeries(name, values); ingo@617: ingo@617: plot.setDataset(0, dataset); ingo@617: } ingo@617: ingo@617: ingo@767: /** ingo@767: * Method which scans the hole bunch of values and returns an array with ingo@767: * contains min and max value. Min value is stored at position 0, max value ingo@767: * is stored at position 1 in that array. ingo@767: * ingo@767: * @param values Array which contains all values ingo@767: * ingo@767: * @return Array which contains min and max value ingo@767: */ ingo@629: protected double[] getMinMax(double[] values) { ingo@1055: if (minmax != null) ingo@1055: return minmax; ingo@1055: ingo@629: double[] minmax = new double[2]; ingo@629: minmax[0] = Double.MAX_VALUE; ingo@629: minmax[1] = Double.MIN_VALUE; ingo@629: ingo@629: int length = values.length; ingo@629: for (int i = 0; i < length; i++) { ingo@629: minmax[0] = values[i] < minmax[0] ? values[i] : minmax[0]; ingo@629: minmax[1] = values[i] > minmax[1] ? values[i] : minmax[1]; ingo@629: } ingo@629: ingo@1055: this.minmax = minmax; ingo@1055: ingo@629: return minmax; ingo@629: } ingo@629: ingo@629: ingo@767: /** ingo@767: * Turn a Double[] into a double[]. ingo@767: * ingo@767: * @param array Doube[] ingo@767: * ingo@767: * @return double[] ingo@767: */ ingo@617: protected double[] toDouble(Double[] array) { ingo@617: int length = array.length; ingo@617: double[] values = new double[length]; ingo@617: ingo@617: for(int i = 0; i < length; i++) { ingo@617: values[i] = array[i].doubleValue(); ingo@617: } ingo@617: ingo@617: return values; ingo@617: } ingo@629: ingo@629: ingo@767: /** ingo@1055: * Method to retrieve the number of bins. ingo@767: * ingo@1055: * @return the number of bins that is specified in requestParameter ingo@1055: * or -1 if the number of bins is not the dominant value to calculate the ingo@1055: * width of a single bin. ingo@767: */ ingo@1055: protected int getBinCount() { ingo@1055: // Return -1 to trigger a calculation of the number of bins in ingo@1055: // AdvancedHistogramDataset if the user chose the bin width as dominant ingo@1055: // value. ingo@1055: String choice = (String) requestParameter.get(REQUEST_KEY_BIN_CHOICE); ingo@1055: if (choice != null && choice.equalsIgnoreCase(REQUEST_KEY_BIN_WIDTH)) { ingo@1055: return -1; ingo@629: } ingo@629: ingo@629: int bins = -1; ingo@629: String param = (String) requestParameter.get(REQUEST_KEY_BIN_COUNT); ingo@629: ingo@629: try { ingo@629: bins = Integer.parseInt(param); ingo@629: bins = bins <= 0 ? DEFAULT_BINS : bins; ingo@629: bins = bins > MAXIMAL_BINS ? MAXIMAL_BINS : bins; ingo@629: ingo@629: return bins; ingo@629: } ingo@629: catch (NumberFormatException nfe) { ingo@629: logger.warn("Invalid number of bins for histogram chart: " + param); ingo@629: logger.warn("Return default bins: " + DEFAULT_BINS); ingo@629: ingo@629: return DEFAULT_BINS; ingo@629: } ingo@629: } ingo@629: ingo@629: ingo@767: /** ingo@1055: * Serves width of a single bin. ingo@767: * ingo@767: * @param values All values in this histogram ingo@767: * ingo@1055: * @return The bin width that is given in requestParameter or -1 if ingo@1055: * the bin width is not the dominant value for calculating the number of ingo@1055: * bins in the histogram. ingo@767: */ ingo@1055: protected double getBinWidth(double[] values) { ingo@1055: // Return -1 to trigger a calculation of the bin width in ingo@1055: // AdvancedHistogramDataset if the user chose the number of bins as ingo@1055: // dominant value. ingo@1055: String choice = (String) requestParameter.get(REQUEST_KEY_BIN_CHOICE); ingo@1055: if (choice == null || !choice.equalsIgnoreCase(REQUEST_KEY_BIN_WIDTH)) { ingo@1055: return -1; ingo@1055: } ingo@1055: ingo@1055: int bins = -1; ingo@1055: String param = (String) requestParameter.get(REQUEST_KEY_BIN_WIDTH); ingo@629: ingo@1054: double[] minmax = getMinMax(values); ingo@1054: double totalWidth = minmax[1] - minmax[0]; ingo@1054: double binWidth = Double.parseDouble(param); ingo@629: ingo@1054: double tmpBins = totalWidth / binWidth; ingo@629: ingo@1054: bins = (int) Math.round(tmpBins); ingo@1054: bins = bins <= 0 ? DEFAULT_BINS : bins; ingo@629: ingo@1055: // the calculated number of bins with the given width exceed the maximum ingo@1055: // number of bins. ingo@1055: if (bins > MAXIMAL_BINS) { ingo@1055: return totalWidth / (MAXIMAL_BINS); ingo@1055: } ingo@1055: ingo@1055: return binWidth; ingo@629: } ingo@617: } ingo@617: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf-8 :