org.eclipse.tracecompass.tmf.ui/src/org/eclipse/tracecompass/tmf/ui/viewers/xycharts/barcharts/TmfBarChartViewer.java

   1 /**********************************************************************
   2  * Copyright (c) 2013, 2014 Ericsson
   3  *
   4  * All rights reserved. This program and the accompanying materials are
   5  * made available under the terms of the Eclipse Public License v1.0 which
   6  * accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *   Alexandre Montplaisir - Initial API and implementation
  11  *   Bernd Hufmann - Updated for TMF base chart viewer
  12  **********************************************************************/
  13 package org.eclipse.tracecompass.tmf.ui.viewers.xycharts.barcharts;
  14
  15 import java.util.ArrayList;
  16 import java.util.List;
  17
  18 import org.eclipse.swt.graphics.Color;
  19 import org.eclipse.swt.graphics.RGB;
  20 import org.eclipse.swt.widgets.Composite;
  21 import org.eclipse.swt.widgets.Display;
  22 import org.eclipse.tracecompass.tmf.ui.viewers.xycharts.TmfChartTimeStampFormat;
  23 import org.eclipse.tracecompass.tmf.ui.viewers.xycharts.TmfXYChartViewer;
  24 import org.swtchart.Chart;
  25 import org.swtchart.IAxisTick;
  26 import org.swtchart.IBarSeries;
  27 import org.swtchart.ISeries;
  28 import org.swtchart.ISeries.SeriesType;
  29
  30 /**
  31  * Abstract bar chart viewer class implementation. Used for displaying
  32  * histograms.
  33  *
  34  * @author Alexandre Montplaisir
  35  * @author Bernd Hufmann
  36  */
  37 public abstract class TmfBarChartViewer extends TmfXYChartViewer {
  38
  39     // ------------------------------------------------------------------------
  40     // Constants
  41     // ------------------------------------------------------------------------
  42     /** Width of each histogram bar, in pixels */
  43     public static final int MINIMUM_BAR_WIDTH = 1;
  44
  45     // ------------------------------------------------------------------------
  46     // Attributes
  47     // ------------------------------------------------------------------------
  48     /** List of series */
  49     private final List<String> seriesNames = new ArrayList<>();
  50     /** List of colors */
  51     private final List<RGB> colors = new ArrayList<>();
  52     /** the bar width */
  53     private int fBarWidth = MINIMUM_BAR_WIDTH;
  54
  55     // ------------------------------------------------------------------------
  56     // Constructors
  57     // ------------------------------------------------------------------------
  58     /**
  59      * Constructs a TmfXYChartViewer.
  60      *
  61      * @param parent
  62      *            The parent composite
  63      * @param title
  64      *            The title of the viewer
  65      * @param xLabel
  66      *            The label of the xAxis
  67      * @param yLabel
  68      *            The label of the yAXIS
  69      * @param barWidth
  70      *            The bar width
  71      */
  72     public TmfBarChartViewer(Composite parent, String title, String xLabel, String yLabel, int barWidth) {
  73         super(parent, title, xLabel, yLabel);
  74         fBarWidth = barWidth;
  75
  76         setTooltipProvider(new TmfHistogramTooltipProvider(this));
  77     }
  78
  79     // ------------------------------------------------------------------------
  80     // Operations
  81     // ------------------------------------------------------------------------
  82     @Override
  83     protected void updateContent() {
  84
  85         getDisplay().asyncExec(new Runnable() {
  86
  87             @Override
  88             public void run() {
  89                 Chart swtChart = getSwtChart();
  90                 int numRequests = swtChart.getPlotArea().getBounds().width / fBarWidth;
  91
  92                 for (int i = 0; i < seriesNames.size(); i++) {
  93                     ISeries series = swtChart.getSeriesSet().getSeries(seriesNames.get(i));
  94                     if (series == null) {
  95                         series = initSeries(seriesNames.get(i), colors.get(i));
  96                     }
  97                     readData(series, getWindowStartTime(), getWindowEndTime(), numRequests);
  98                 }
  99             }
 100         });
 101     }
 102
 103     /**
 104      * Method to add a series to the chart.
 105      *
 106      * @param name
 107      *            Name of series
 108      * @param color
 109      *            color to use for series
 110      */
 111     protected void addSeries(String name, RGB color) {
 112         seriesNames.add(name);
 113         colors.add(color);
 114     }
 115
 116     /**
 117      * Clears all series
 118      */
 119     protected void clearSeries() {
 120         seriesNames.clear();
 121         colors.clear();
 122     }
 123
 124     /**
 125      * Draw the given series on the chart
 126      *
 127      * @param series
 128      *            The series to display
 129      * @param x
 130      *            The X values. It can be computed with
 131      *            {@link TmfBarChartViewer#getXAxis}
 132      *            The values are stored in the internal time representation.
 133      *            To get the trace time one has to add the time offset
 134      *            {@link #getTimeOffset()}.
 135      * @param y
 136      *            The Y values that were computed by the extended class
 137      */
 138     protected void drawChart(final ISeries series, final double[] x, final double[] y) {
 139         // Run in GUI thread to make sure that chart is ready after restart
 140         final Display display = getDisplay();
 141         if (display.isDisposed()) {
 142             return;
 143         }
 144
 145         display.syncExec(new Runnable() {
 146             @Override
 147             public void run() {
 148                 if (display.isDisposed()) {
 149                     return;
 150                 }
 151                 Chart swtChart = getSwtChart();
 152                 IAxisTick xTick = swtChart.getAxisSet().getXAxis(0).getTick();
 153                 xTick.setFormat(new TmfChartTimeStampFormat(getTimeOffset()));
 154                 series.setXSeries(x);
 155                 series.setYSeries(y);
 156                 xTick.setTickMarkStepHint(256);
 157
 158                 swtChart.getAxisSet().adjustRange();
 159                 swtChart.redraw();
 160             }
 161         });
 162     }
 163
 164     /**
 165      * Convenience method to compute the X axis values for a given time range.
 166      *
 167      * @param start
 168      *            Start of the time range
 169      * @param end
 170      *            End of the range
 171      * @param nb
 172      *            Number of steps. This will be the size of the returned array.
 173      * @return The time values (converted to double) that match every step
 174      */
 175     protected final double[] getXAxis(long start, long end, int nb) {
 176         setTimeOffset(start - 1);
 177         double timestamps[] = new double[nb];
 178         long steps = (end - start);
 179         double step = steps / (double) nb;
 180
 181         double curTime = 1;
 182         for (int i = 0; i < nb; i++) {
 183             timestamps[i] = curTime;
 184             curTime += step;
 185         }
 186         return timestamps;
 187     }
 188
 189     /**
 190      * Load the data for the given series. This method should call
 191      * {@link TmfBarChartViewer#drawChart} to return the results when done.
 192      *
 193      * Careful, this method is called by a signal handler which also happens to
 194      * be in the main UI thread. This means any processing will block the UI! In
 195      * most cases it's probably better to start a separate Thread/Job to do the
 196      * processing, and that one can call drawChart() when done to update the
 197      * view.
 198      *
 199      * @param series
 200      *            Which series of the chart should the viewer update
 201      * @param start
 202      *            The start time (in nanoseconds) of the range to display
 203      * @param end
 204      *            The end time of the range to display.
 205      * @param nb
 206      *            The number of 'steps' in the bar chart (fewer steps means each
 207      *            bar is wider).
 208      */
 209     protected abstract void readData(ISeries series, long start, long end, int nb);
 210
 211     // initializes a series
 212     private IBarSeries initSeries(String name, RGB color) {
 213         IBarSeries bs = (IBarSeries) getSwtChart().getSeriesSet().createSeries(SeriesType.BAR, name);
 214         bs.enableStack(true);
 215         bs.setBarColor(new Color(Display.getDefault(), color));
 216         bs.setBarPadding(0);
 217         return bs;
 218     }
 219 }