/** * Licensed under the Artistic License; you may not use this file * except in compliance with the License. * You may obtain a copy of the License at * *      http://displaytag.sourceforge.net/license.html * * THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. */package org.displaytag.decorator;import java.text.MessageFormat;import java.util.HashMap;import java.util.Iterator;import java.util.List;import java.util.Map;import javax.servlet.jsp.PageContext;import org.apache.commons.lang.ObjectUtils;import org.apache.commons.lang.StringUtils;import org.apache.commons.logging.Log;import org.apache.commons.logging.LogFactory;import org.displaytag.exception.DecoratorException;import org.displaytag.model.HeaderCell;import org.displaytag.model.TableModel;/** * A table decorator which adds rows with totals (for column with the "total" attribute set) and subtotals (grouping by * the column with a group="1" attribute). * @author Fabrizio Giustina * @version $Id$ */public class TotalTableDecorator extends TableDecorator{    /**     * Logger.     */    private static Log log = LogFactory.getLog(TotalTableDecorator.class);    /**     * total amount.     */    private Map grandTotals = new HashMap();    /**     * total amount for current group.     */    private Map subTotals = new HashMap();    /**     * Previous values needed for grouping.     */    private Map previousValues = new HashMap();    /**     * Name of the property used for grouping.     */    private String groupPropertyName;    /**     * Label used for subtotals. Default: "{0} total".     */    private String subtotalLabel = "{0} subtotal";    /**     * Label used for totals. Default: "Total".     */    private String totalLabel = "Total";    /**     * Setter for <code>subtotalLabel</code>.     * @param subtotalLabel The subtotalLabel to set.     */    public void setSubtotalLabel(String subtotalLabel)    {        this.subtotalLabel = subtotalLabel;    }    /**     * Setter for <code>totalLabel</code>.     * @param totalLabel The totalLabel to set.     */    public void setTotalLabel(String totalLabel)    {        this.totalLabel = totalLabel;    }    /**     * @see org.displaytag.decorator.Decorator#init(PageContext, Object, TableModel)     */    public void init(PageContext context, Object decorated, TableModel tableModel)    {        super.init(context, decorated, tableModel);        // reset        groupPropertyName = null;        grandTotals.clear();        subTotals.clear();        previousValues.clear();        for (Iterator it = tableModel.getHeaderCellList().iterator(); it.hasNext();)        {            HeaderCell cell = (HeaderCell) it.next();            if (cell.getGroup() == 1)            {                groupPropertyName = cell.getBeanPropertyName();            }        }    }    public String startRow()    {        String subtotalRow = null;        if (groupPropertyName != null)        {            Object groupedPropertyValue = evaluate(groupPropertyName);            Object previousGroupedPropertyValue = previousValues.get(groupPropertyName);            // subtotals            if (previousGroupedPropertyValue != null                && !ObjectUtils.equals(previousGroupedPropertyValue, groupedPropertyValue))            {                subtotalRow = createTotalRow(false);            }            previousValues.put(groupPropertyName, groupedPropertyValue);        }        for (Iterator it = tableModel.getHeaderCellList().iterator(); it.hasNext();)        {            HeaderCell cell = (HeaderCell) it.next();            if (cell.isTotaled())            {                String totalPropertyName = cell.getBeanPropertyName();                Number amount = (Number) evaluate(totalPropertyName);                Number previousSubTotal = (Number) subTotals.get(totalPropertyName);                Number previousGrandTotals = (Number) grandTotals.get(totalPropertyName);                subTotals.put(totalPropertyName, new Double((previousSubTotal != null                    ? previousSubTotal.doubleValue()                    : 0)                    + (amount != null ? amount.doubleValue() : 0)));                grandTotals.put(totalPropertyName, new Double((previousGrandTotals != null ? previousGrandTotals                    .doubleValue() : 0)                    + (amount != null ? amount.doubleValue() : 0)));            }        }        return subtotalRow;    }    /**     * After every row completes we evaluate to see if we should be drawing a new total line and summing the results     * from the previous group.     * @return String     */    public final String finishRow()    {        StringBuffer buffer = new StringBuffer(1000);        // Grand totals...        if (getViewIndex() == ((List) getDecoratedObject()).size() - 1)        {            if (groupPropertyName != null)            {                buffer.append(createTotalRow(false));            }            buffer.append(createTotalRow(true));        }        return buffer.toString();    }    protected String createTotalRow(boolean grandTotal)    {        StringBuffer buffer = new StringBuffer(1000);        buffer.append("\n<tr class=\"total\">"); //$NON-NLS-1$        List headerCells = tableModel.getHeaderCellList();        for (Iterator it = headerCells.iterator(); it.hasNext();)        {            HeaderCell cell = (HeaderCell) it.next();            String cssClass = ObjectUtils.toString(cell.getHtmlAttributes().get("class"));            buffer.append("<td"); //$NON-NLS-1$            if (StringUtils.isNotEmpty(cssClass))            {                buffer.append(" class=\""); //$NON-NLS-1$                buffer.append(cssClass);                buffer.append("\""); //$NON-NLS-1$            }            buffer.append(">"); //$NON-NLS-1$            if (cell.isTotaled())            {                String totalPropertyName = cell.getBeanPropertyName();                Object total = grandTotal ? grandTotals.get(totalPropertyName) : subTotals.get(totalPropertyName);                DisplaytagColumnDecorator[] decorators = cell.getColumnDecorators();                for (int j = 0; j < decorators.length; j++)                {                    try                    {                        total = decorators[j].decorate(total, this.getPageContext(), tableModel.getMedia());                    }                    catch (DecoratorException e)                    {                        log.warn(e.getMessage(), e);                        // ignore, use undecorated value for totals                    }                }                buffer.append(total);            }            else if (groupPropertyName != null && groupPropertyName.equals(cell.getBeanPropertyName()))            {                buffer.append(grandTotal ? totalLabel : MessageFormat.format(subtotalLabel, new Object[]{previousValues                    .get(groupPropertyName)}));            }            buffer.append("</td>"); //$NON-NLS-1$        }        buffer.append("</tr>"); //$NON-NLS-1$        // reset subtotal        this.subTotals.clear();        return buffer.toString();    }}