abstractcellrenderer.java

webwork source

/*
 * @author      Walter Szewelanczyk
 * @version 0.02
 * date    Sept 09, 2001
 */
package webwork.view.taglib.ui.table.renderer;

import webwork.view.taglib.ui.table.WebTable;


/**
 * this is the base class that most renderers will be derived from.
 * It allows setting the alignment.  Subclasses should set there actuall
 * content by implementing getCellValue
 */
abstract public class AbstractCellRenderer implements CellRenderer
{
	/**
	 * used for horizontal cell alignmnet
	 */
	protected String _alignment = null;

	protected boolean isAligned()
	{
		return _alignment != null;
	}

	public String getAlignment()
	{
		return _alignment;
	}

	public void setAlignment(String alignment)
	{
		_alignment = alignment;
	}

	/**
	 * implememnts CellRenderer renderCell.  It sets the alignment.  gets the actual
	 * data from getCellValue
	 */
	public String renderCell(WebTable table, Object data, int row, int col)
	{
		if(isAligned())
		{
			StringBuffer buf = new StringBuffer(256);
			buf.append("<div align='").append(_alignment).append("'>");
			buf.append(getCellValue(table, data, row, col));
			buf.append("</div>");
			return buf.toString();
		}
		return getCellValue(table, data, row, col);
	}

	/**
	 * this is the method that subclasses need to implement to set their value.
	 * they should not override renderCell unless they want to change the alignmnent
	 * renderering
	 */
	abstract protected String getCellValue(WebTable table, Object data, int row, int col);
}