/** * 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.io.IOException;import java.util.ArrayList;import java.util.Arrays;import java.util.Iterator;import java.util.List;import java.util.Map;import javax.servlet.jsp.JspWriter;import javax.servlet.jsp.PageContext;import org.apache.commons.lang.ObjectUtils;import org.displaytag.model.TableModel;/** * A table decorator which adds checkboxes for selectable rows. * @author Fabrizio Giustina * @version $Id: CheckboxTableDecorator.java 1134 2008-12-27 10:16:33Z fgiust $ */public class CheckboxTableDecorator extends TableDecorator{    private String id = "id";    private Map params;    private List checkedIds;    private String fieldName = "_chk";    /**     * Setter for <code>id</code>.     * @param id The id to set.     */    public void setId(String id)    {        this.id = id;    }    /**     * Setter for <code>fieldName</code>.     * @param fieldName The fieldName to set.     */    public void setFieldName(String fieldName)    {        this.fieldName = fieldName;    }    /**     * @see org.displaytag.decorator.Decorator#init(javax.servlet.jsp.PageContext, java.lang.Object,     * org.displaytag.model.TableModel)     */    public void init(PageContext pageContext, Object decorated, TableModel tableModel)    {        super.init(pageContext, decorated, tableModel);        String[] params = pageContext.getRequest().getParameterValues(fieldName);        checkedIds = params != null ? new ArrayList(Arrays.asList(params)) : new ArrayList(0);    }    /**     * @see org.displaytag.decorator.TableDecorator#finish()     */    public void finish()    {        if (!checkedIds.isEmpty())        {            JspWriter writer = getPageContext().getOut();            for (Iterator it = checkedIds.iterator(); it.hasNext();)            {                String name = (String) it.next();                StringBuffer buffer = new StringBuffer();                buffer.append("<input type=\"hidden\" name=\"");                buffer.append(fieldName);                buffer.append("\" value=\"");                buffer.append(name);                buffer.append("\">");                try                {                    writer.write(buffer.toString());                }                catch (IOException e)                {                    // should never happen                }            }        }        super.finish();    }    public String getCheckbox()    {        String evaluatedId = ObjectUtils.toString(evaluate(id));        boolean checked = checkedIds.contains(evaluatedId);        StringBuffer buffer = new StringBuffer();        buffer.append("<input type=\"checkbox\" name=\"_chk\" value=\"");        buffer.append(evaluatedId);        buffer.append("\"");        if (checked)        {            checkedIds.remove(evaluatedId);            buffer.append(" checked=\"checked\"");        }        buffer.append("/>");        return buffer.toString();    }}