/** * 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.model;import java.util.Iterator;import java.util.List;/** * Iterator on columns. * @author Fabrizio Giustina * @version $Revision: 1081 $ ($Author: fgiust $) */public class ColumnIterator{    /**     * current row.     */    private Row parentRow;    /**     * Internal iterator on header cells.     */    private Iterator headerIterator;    /**     * Internal iterator on cells.     */    private Iterator cellIterator;    /**     * Creates a new ColumnIterator given a list of column and a row.     * @param columns List containing column objects     * @param row current Row     */    public ColumnIterator(List columns, Row row)    {        this.headerIterator = columns.iterator();        this.cellIterator = row.getCellList().iterator();        this.parentRow = row;    }    /**     * Are there more columns?     * @return boolean <code>true</code> if there are more columns     */    public boolean hasNext()    {        return this.headerIterator.hasNext();    }    /**     * Returns the next column.     * @return Column next column     */    public Column nextColumn()    {        HeaderCell header = (HeaderCell) this.headerIterator.next();        Cell cell = Cell.EMPTY_CELL;        // if cells is not present simply return an empty cell.        // this is needed for automatic properties discovery        if (this.cellIterator.hasNext())        {            cell = (Cell) this.cellIterator.next();        }        // create a new column using the next value in the header and cell iterators and returns it        return new Column(header, cell, this.parentRow);    }}