/** * 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.sample.decorators;import java.util.List;import org.apache.commons.lang.ObjectUtils;import org.displaytag.decorator.TableDecorator;import org.displaytag.sample.ReportableListObject;/** * Same idea implemented in TableWriterTemplate applied to decorators. * @see org.displaytag.render.TableWriterTemplate * @author Jorge L. Barroso * @version $Revision$ ($Author$) */public abstract class TotalWrapperTemplate extends TableDecorator{    /**     * total amount.     */    private double grandTotal;    /**     * total amount for city.     */    private double cityTotal;    /**     * Obtain the <code>StringBuffer</code> used to build the totals line.     */    private StringBuffer buffer;    /**     * 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()    {        int listindex = ((List) getDecoratedObject()).indexOf(this.getCurrentRowObject());        ReportableListObject reportableObject = (ReportableListObject) this.getCurrentRowObject();        String nextCity = null;        this.cityTotal += reportableObject.getAmount();        this.grandTotal += reportableObject.getAmount();        if (listindex != ((List) getDecoratedObject()).size() - 1)        {            nextCity = ((ReportableListObject) ((List) getDecoratedObject()).get(listindex + 1)).getCity();        }        this.buffer = new StringBuffer(1000);        // City subtotals...        if (!ObjectUtils.equals(nextCity, reportableObject.getCity()))        {            writeCityTotal(reportableObject.getCity(), this.cityTotal);            this.cityTotal = 0;        }        // Grand totals...        if (getViewIndex() == ((List) getDecoratedObject()).size() - 1)        {            writeGrandTotal(this.grandTotal);        }        return buffer.toString();    }    /**     * Render the city total in the appropriate format.     * @param city The city name to render.     * @param total The city total to render.     */    abstract protected void writeCityTotal(String city, double total);    /**     * Render the grand total in the appropriate format.     * @param total The grand total to render.     */    abstract protected void writeGrandTotal(double total);    /**     * Obtain the <code>StringBuffer</code> used to build the totals line.     * @return The <code>StringBuffer</code> used to build the totals line.     */    protected StringBuffer getStringBuffer()    {        return this.buffer;    }}