numericcellrenderer.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;

import java.text.DecimalFormat;

public class NumericCellRenderer extends AbstractCellRenderer
{
	/**
	 * if set this is the color to render if number is positive
	 */
	String _positiveColor = null;

	/**
	 * if set the is the color to use if Number is negative.
	 */
	String _negativeColor = null;

	/**
	 * this is the format string that DecimalFormat would use.
	 * @see DecimalFormat
	 */
	String _formatString  = null;
	DecimalFormat _formater = new DecimalFormat();

	public NumericCellRenderer()
	{
		super();
	}

	public String getCellValue(WebTable table, Object data, int row, int col)
	{
		StringBuffer retVal = new StringBuffer(128);

		if(data == null)
		{
			return "";
		}

		if(data instanceof Number)
		{
			double cellValue = ((Number)data).doubleValue();
			if(cellValue >= 0)
			{
				processNumber(retVal, _positiveColor, cellValue);
			}
			else
			{
				processNumber(retVal, _negativeColor, cellValue);
			}
			return retVal.toString();
		}

		return data.toString();
	}

	protected void processNumber(StringBuffer buf, String color, double cellValue)
	{
		if(color != null)
		{
			buf.append(" <font color='").append(color).append("'>");
		}
		buf.append(_formater.format(cellValue));
		if(color != null)
		{
			buf.append("</font>");
		}
	}

	public void setPositiveColor(String color)
	{
		_positiveColor = color;
	}

	public void setNegativeColor(String color)
	{
		_negativeColor = color;
	}

	public void setFormatString(String format)
	{
		_formatString = format;
		_formater.applyPattern(_formatString);
	}
}