org.pentaho.chart.plugin.api.ChartItemLabelGenerator.java Source code

Introduction

Here is the source code for org.pentaho.chart.plugin.api.ChartItemLabelGenerator.java

Source

/*!
* This program is free software; you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
* Foundation.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* or from the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* This program 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 Lesser General Public License for more details.
*
* Copyright (c) 2002-2017 Hitachi Vantara..  All rights reserved.
*/

package org.pentaho.chart.plugin.api;

import java.text.MessageFormat;
import java.util.HashMap;
import java.util.Map;

import org.jfree.chart.labels.StandardCategoryItemLabelGenerator;
import org.jfree.data.category.CategoryDataset;
import org.pentaho.chart.core.ChartElement;
import org.pentaho.chart.css.keys.ChartStyleKeys;
import org.pentaho.chart.data.ChartTableModel;
import org.pentaho.reporting.libraries.css.dom.LayoutStyle;
import org.pentaho.reporting.libraries.css.keys.font.FontStyleKeys;
import org.pentaho.reporting.libraries.css.keys.font.FontVariant;
import org.pentaho.reporting.libraries.css.values.CSSStringValue;
import org.pentaho.reporting.libraries.css.values.CSSValue;

/**
 * This class handles the ItemLabel generation and numeric formatting.
 *
 * @author Ravi Hasija
 */
public class ChartItemLabelGenerator extends StandardCategoryItemLabelGenerator {
    private ChartElement[] chartElements;
    private Map<Integer, ChartElement> map;
    private Map<String, Integer> columnPositions;

    public ChartItemLabelGenerator(final ChartElement[] chartElements, final ChartTableModel chartData) {
        this.chartElements = chartElements;
        this.map = new HashMap<Integer, ChartElement>();
        this.columnPositions = new HashMap<String, Integer>();

        // Get the column number for a particular series and store the information in the map
        mapSeriesToColumnNumber();

        if (chartData != null) {
            for (int i = 0; i < chartData.getColumnCount(); i++) {
                final String columnName = chartData.getColumnName(i);
                columnPositions.put(columnName, Integer.valueOf(i));
            }
        }
    }

    /**
     *
     */
    private static final long serialVersionUID = -1787452968861210575L;

    /**
     * This method is over-ridden to get the actual data value into the item label along with
     * custom formatting defined for the series in the chart definition document.
     * {0} maps to data value
     * {1} maps to column name
     *
     * @param dataset category dataset
     * @param row     Row number
     * @param column  Column number
     * @return String Final label string for the given series
     */
    public String generateLabel(final CategoryDataset dataset, final int row, final int column) {
        if (dataset == null) {
            return null;
        }
        try {
            final Object data = dataset.getValue(row, column);
            if (data != null) {
                final ChartElement ce = map.get(Integer.valueOf(column));
                if (ce != null) {
                    final LayoutStyle layoutStyle = ce.getLayoutStyle();

                    //Format the item label text
                    final String messageFormat = ((CSSStringValue) layoutStyle
                            .getValue(ChartStyleKeys.ITEM_LABEL_TEXT)).getValue();//$NON-NLS-1$
                    String result = MessageFormat.format(messageFormat, data, dataset.getColumnKey(column));

                    //Get the font variant to convert the label text to upper case if the
                    //font variant is set to small-caps
                    final CSSValue variant = layoutStyle.getValue(FontStyleKeys.FONT_VARIANT);
                    if (FontVariant.SMALL_CAPS.equals(variant)) {
                        result = result.toUpperCase();
                    }
                    return result;
                }
            }
        } catch (IndexOutOfBoundsException ignore) {
            //Ignore this exception as we are not directly causing it.
        }

        return null;
    }

    /*
    * TODO: mapSeriesToColumnNumber(),
    *       getSeriesColumn(ChartElement seriesElement, int columnDefault),
    *       and lookupPosition methods are from JFreeChartUtils class.
    *  To not make this class dependent on JFreeChartUtils, the methods above
    *  were copied to this class. We need to move these methods to a commons class.
    */
    private void mapSeriesToColumnNumber() {
        if (chartElements != null) {
            for (int i = 0; i < chartElements.length; i++) {
                ChartElement element = chartElements[i];
                final int columnNum = getSeriesColumn(element, i);
                map.put(Integer.valueOf(columnNum), element);
            }
        }
    }

    private int getSeriesColumn(final ChartElement seriesElement, final int columnDefault) {
        int column = columnDefault;

        if (seriesElement != null) {
            Object positionAttr = seriesElement.getAttribute("column-pos"); //$NON-NLS-1$
            if (positionAttr != null) {
                column = Integer.parseInt(positionAttr.toString());
            } else {
                positionAttr = seriesElement.getAttribute("column-name"); //$NON-NLS-1$
                if (positionAttr != null) {
                    column = lookupPosition(positionAttr.toString());
                }
            }
        }
        return column;
    }

    private int lookupPosition(final String columnName) {
        final Integer integer = columnPositions.get(columnName.toLowerCase());
        if (integer == null) {
            return -1;
        }
        return integer.intValue();
    }
}