path: root/projects/net.wotonomy.ui.swing/src/main/java/net/wotonomy/ui/swing/components/FormattedCellRenderer.java

/*
Wotonomy: OpenStep design patterns for pure Java applications.
Copyright (C) 2000 Blacksmith, Inc.

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, see http://www.gnu.org
*/

package net.wotonomy.ui.swing.components;

import java.awt.Color;
import java.awt.Component;
import java.awt.Font;
import java.text.Format;

import javax.swing.JTable;
import javax.swing.table.DefaultTableCellRenderer;

/**
 * A cell renderer for dealing with formatted content. Subclasses can specify
 * formats or colors or styles for specific values or locations in the table by
 * overridding getFormatForContext(), getForegroundForContext() and/or
 * getBackgroundForContext().
 *
 * @author michael@mpowers.net
 * @version $Revision: 904 $ $Date: 2006-02-18 18:19:05 -0500 (Sat, 18 Feb 2006)
 *          $
 */
public class FormattedCellRenderer extends DefaultTableCellRenderer {
	protected Format currentFormat, defaultFormat;
	protected Color defaultForeground, defaultBackground;
	protected Font defaultFont;

	/**
	 * Default constructor with no specified format.
	 */
	public FormattedCellRenderer() {
		this((Format) null);
	}

	/**
	 * Constructor specifying a format for renderered content.
	 */
	public FormattedCellRenderer(Format aFormat) {
		currentFormat = null;
		defaultFormat = aFormat;
		defaultForeground = super.getForeground();
		defaultBackground = super.getForeground();
	}

	/**
	 * Returns the format currently in use to format cell content.
	 * 
	 * @return The Format that is currently being used.
	 */
	public Format getFormat() {
		return defaultFormat;
	}

	/**
	 * Sets the format to be used to format cell content.
	 */
	public void setFormat(Format aFormat) {
		defaultFormat = aFormat;
	}

	/**
	 * Overrides to retain the default foreground color, much the same as the
	 * DefaultCellRenderer does. We have to do this because DefaultCellRenderer's
	 * ivars are private.
	 */
	public void setForeground(Color c) {
		super.setForeground(c);
		defaultForeground = c;
	}

	/**
	 * Overrides to retain the default background color, much the same as the
	 * DefaultCellRenderer does. We have to do this because DefaultCellRenderer's
	 * ivars are private.
	 */
	public void setBackground(Color c) {
		super.setBackground(c);
		defaultBackground = c;
	}

	/**
	 * Overrides to retain the default font, much the same as the
	 * DefaultCellRenderer does. We have to do this because DefaultCellRenderer's
	 * ivars are private.
	 */
	public void setFont(Font f) {
		super.setFont(f);
		defaultFont = f;
	}

	/**
	 * Overridden to format the value with the appropriate Format. If the value
	 * cannot be formatted with the Format, the superclass method is called.
	 * 
	 * @param value An Object to be formatted.
	 */
	protected void setValue(Object value) {
		if (currentFormat != null) {
			try {

// if ( ( value instanceof Number ) && ( value.toString().indexOf( "E" ) != -1 ) )
// {
//     System.out.println( "FormattedCellRenderer.setValue: format = '" + currentFormat.getClass() + "'" );
//     System.out.println( "FormattedCellRenderer.setValue: value = '" + value + "'" );
//     System.out.println( "FormattedCellRenderer.setValue: double value = '" + ((Number)value).doubleValue() + "'" );
//     System.out.println( "FormattedCellRenderer.setValue: float value = '" + ((Number)value).floatValue() + "'" );
//     System.out.println( "FormattedCellRenderer.setValue: converted = '" + currentFormat.format( value ) + "'" );
// }

				// WORKAROUND: This works around what may be a rounding bug in DecimalFormat.
				// (PR 256/297)
				currentFormat.format(ZERO);

				// DEBUG: code to test for weird one/zero problem (PR 256/297)
				String result = currentFormat.format(value);
				/*
				 * above workaround seems to be working if ( result.equals( "1" ) ) {
				 * System.out.println(
				 * "FormattedCellRenderer.setValue: Could be the ONE/ZERO problem!" );
				 * System.out.println( "FormattedCellRenderer.setValue: format = '" +
				 * currentFormat.getClass() + "'" ); System.out.println(
				 * "FormattedCellRenderer.setValue: original value = '" + value + "'" );
				 * System.out.println( "FormattedCellRenderer.setValue: result = '" + result +
				 * "'" ); }
				 */
				setText(result);

//                setText( currentFormat.format( value ) );
				return;
			} catch (IllegalArgumentException exc) {
				// fall back on superclass implementation
			}
		}
		super.setValue(value);
	}

	// FIXME: remove this when possible
	private static Double ZERO = new Double(0.0);

	/**
	 * Overridden to call context delegate methods.
	 */
	public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus,
			int row, int column) {
		Format format;

		// allow for context-sensitve formatting
		format = getFormatForContext(table, value, isSelected, hasFocus, row, column);
		if (format != null) {
			currentFormat = format;
		} else {
			currentFormat = defaultFormat;
		}

		Color color;

		// allow for context-sensitve foreground color
		color = getForegroundForContext(table, value, isSelected, hasFocus, row, column);
		if (color != null) {
			super.setForeground(color);
		} else {
			super.setForeground(defaultForeground);
		}

		// allow for context-sensitve background color
		color = getBackgroundForContext(table, value, isSelected, hasFocus, row, column);
		if (color != null) {
			super.setBackground(color);
		} else {
			super.setBackground(defaultBackground);
		}

		// have to call this here because super defaults to table's font
		Component result = super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);
		// NOTE: DefaultTableCellRenderer returns itself.

		// allow for context-sensitve font
		Font font = getFontForContext(table, value, isSelected, hasFocus, row, column);
		if (font != null) {
			result.setFont(font);
		} else {
			result.setFont(defaultFont);
		}

		return result;

	}

	/**
	 * Override this method to provide a specific format for the specific cell to be
	 * rendered by this component. Any format returned by this method will take
	 * precedence of the format specified by setFormat(). <br>
	 * <br>
	 * This default implementation returns null.
	 * 
	 * @return A Format for this cell, or null to rely on the the format specified
	 *         by setFormat().
	 */
	public Format getFormatForContext(JTable table, Object value, boolean isSelected, boolean hasFocus, int row,
			int column) {
		return null;
	}

	/**
	 * Override this method to provide a foreground color for the renderer. Because
	 * the table specifies colors for selected cells, these colors will only be used
	 * when renderering unselected cells. <br>
	 * <br>
	 * This default implementation returns null.
	 * 
	 * @return A Color for the foreground of the cell, or null to rely on the
	 *         table's default color scheme.
	 */
	public Color getForegroundForContext(JTable table, Object value, boolean isSelected, boolean hasFocus, int row,
			int column) {
		return null;
	}

	/**
	 * Override this method to provide a background color for the renderer. Because
	 * the table specifies colors for selected cells, these colors will only be used
	 * when renderering unselected cells. <br>
	 * <br>
	 * This default implementation returns null.
	 * 
	 * @return A Color for the background of the cell, or null to rely on the
	 *         table's default color scheme.
	 */
	public Color getBackgroundForContext(JTable table, Object value, boolean isSelected, boolean hasFocus, int row,
			int column) {
		return null;
	}

	/**
	 * Override this method to provide a font for the renderer.<br>
	 * <br>
	 * This default implementation returns null.
	 * 
	 * @return A Font for the cell, or null to rely on the table's default font.
	 */
	public Font getFontForContext(JTable table, Object value, boolean isSelected, boolean hasFocus, int row,
			int column) {
		return null;
	}

}