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	/*
	* Copyright (c) 1998, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code 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 General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package javax.swing.table;

	import javax.swing.*;
	import javax.swing.border.*;

	import java.awt.Component;
	import java.awt.Color;
	import java.awt.Rectangle;

	import java.io.Serializable;
	import sun.swing.DefaultLookup;


	/**
	* The standard class for rendering (displaying) individual cells
	* in a <code>JTable</code>.
	* <p>
	*
	* <strong><a name="override">Implementation Note:</a></strong>
	* This class inherits from <code>JLabel</code>, a standard component class.
	* However <code>JTable</code> employs a unique mechanism for rendering
	* its cells and therefore requires some slightly modified behavior
	* from its cell renderer.
	* The table class defines a single cell renderer and uses it as a
	* as a rubber-stamp for rendering all cells in the table;
	* it renders the first cell,
	* changes the contents of that cell renderer,
	* shifts the origin to the new location, re-draws it, and so on.
	* The standard <code>JLabel</code> component was not
	* designed to be used this way and we want to avoid
	* triggering a <code>revalidate</code> each time the
	* cell is drawn. This would greatly decrease performance because the
	* <code>revalidate</code> message would be
	* passed up the hierarchy of the container to determine whether any other
	* components would be affected.
	* As the renderer is only parented for the lifetime of a painting operation
	* we similarly want to avoid the overhead associated with walking the
	* hierarchy for painting operations.
	* So this class
	* overrides the <code>validate</code>, <code>invalidate</code>,
	* <code>revalidate</code>, <code>repaint</code>, and
	* <code>firePropertyChange</code> methods to be
	* no-ops and override the <code>isOpaque</code> method solely to improve
	* performance. If you write your own renderer,
	* please keep this performance consideration in mind.
	* <p>
	*
	* <strong>Warning:</strong>
	* Serialized objects of this class will not be compatible with
	* future Swing releases. The current serialization support is
	* appropriate for short term storage or RMI between applications running
	* the same version of Swing. As of 1.4, support for long term storage
	* of all JavaBeans™
	* has been added to the <code>java.beans</code> package.
	* Please see {@link java.beans.XMLEncoder}.
	*
	* @author Philip Milne
	* @see JTable
	*/
	public class DefaultTableCellRenderer extends JLabel
	implements TableCellRenderer, Serializable
	{

	/**
	* An empty <code>Border</code>. This field might not be used. To change the
	* <code>Border</code> used by this renderer override the
	* <code>getTableCellRendererComponent</code> method and set the border
	* of the returned component directly.
	*/
	private static final Border SAFE_NO_FOCUS_BORDER = new EmptyBorder(1, 1, 1, 1);
	private static final Border DEFAULT_NO_FOCUS_BORDER = new EmptyBorder(1, 1, 1, 1);
	protected static Border noFocusBorder = DEFAULT_NO_FOCUS_BORDER;

	// We need a place to store the color the JLabel should be returned
	// to after its foreground and background colors have been set
	// to the selection background color.
	// These ivars will be made protected when their names are finalized.
	private Color unselectedForeground;
	private Color unselectedBackground;

	/**
	* Creates a default table cell renderer.
	*/
	public DefaultTableCellRenderer() {
	super();
	setOpaque(true);
	setBorder(getNoFocusBorder());
	setName("Table.cellRenderer");
	}

	private Border getNoFocusBorder() {
	Border border = DefaultLookup.getBorder(this, ui, "Table.cellNoFocusBorder");
	if (System.getSecurityManager() != null) {
	if (border != null) return border;
	return SAFE_NO_FOCUS_BORDER;
	} else if (border != null) {
	if (noFocusBorder == null \|\| noFocusBorder == DEFAULT_NO_FOCUS_BORDER) {
	return border;
	}
	}
	return noFocusBorder;
	}

	/**
	* Overrides <code>JComponent.setForeground</code> to assign
	* the unselected-foreground color to the specified color.
	*
	* @param c set the foreground color to this value
	*/
	public void setForeground(Color c) {
	super.setForeground(c);
	unselectedForeground = c;
	}

	/**
	* Overrides <code>JComponent.setBackground</code> to assign
	* the unselected-background color to the specified color.
	*
	* @param c set the background color to this value
	*/
	public void setBackground(Color c) {
	super.setBackground(c);
	unselectedBackground = c;
	}

	/**
	* Notification from the <code>UIManager</code> that the look and feel
	* [L&F] has changed.
	* Replaces the current UI object with the latest version from the
	* <code>UIManager</code>.
	*
	* @see JComponent#updateUI
	*/
	public void updateUI() {
	super.updateUI();
	setForeground(null);
	setBackground(null);
	}

	// implements javax.swing.table.TableCellRenderer
	/**
	*
	* Returns the default table cell renderer.
	* <p>
	* During a printing operation, this method will be called with
	* <code>isSelected</code> and <code>hasFocus</code> values of
	* <code>false</code> to prevent selection and focus from appearing
	* in the printed output. To do other customization based on whether
	* or not the table is being printed, check the return value from
	* {@link javax.swing.JComponent#isPaintingForPrint()}.
	*
	* @param table the <code>JTable</code>
	* @param value the value to assign to the cell at
	* <code>[row, column]</code>
	* @param isSelected true if cell is selected
	* @param hasFocus true if cell has focus
	* @param row the row of the cell to render
	* @param column the column of the cell to render
	* @return the default table cell renderer
	* @see javax.swing.JComponent#isPaintingForPrint()
	*/
	public Component getTableCellRendererComponent(JTable table, Object value,
	boolean isSelected, boolean hasFocus, int row, int column) {
	if (table == null) {
	return this;
	}

	Color fg = null;
	Color bg = null;

	JTable.DropLocation dropLocation = table.getDropLocation();
	if (dropLocation != null
	&& !dropLocation.isInsertRow()
	&& !dropLocation.isInsertColumn()
	&& dropLocation.getRow() == row
	&& dropLocation.getColumn() == column) {

	fg = DefaultLookup.getColor(this, ui, "Table.dropCellForeground");
	bg = DefaultLookup.getColor(this, ui, "Table.dropCellBackground");

	isSelected = true;
	}

	if (isSelected) {
	super.setForeground(fg == null ? table.getSelectionForeground()
	: fg);
	super.setBackground(bg == null ? table.getSelectionBackground()
	: bg);
	} else {
	Color background = unselectedBackground != null
	? unselectedBackground
	: table.getBackground();
	if (background == null \|\| background instanceof javax.swing.plaf.UIResource) {
	Color alternateColor = DefaultLookup.getColor(this, ui, "Table.alternateRowColor");
	if (alternateColor != null && row % 2 != 0) {
	background = alternateColor;
	}
	}
	super.setForeground(unselectedForeground != null
	? unselectedForeground
	: table.getForeground());
	super.setBackground(background);
	}

	setFont(table.getFont());

	if (hasFocus) {
	Border border = null;
	if (isSelected) {
	border = DefaultLookup.getBorder(this, ui, "Table.focusSelectedCellHighlightBorder");
	}
	if (border == null) {
	border = DefaultLookup.getBorder(this, ui, "Table.focusCellHighlightBorder");
	}
	setBorder(border);

	if (!isSelected && table.isCellEditable(row, column)) {
	Color col;
	col = DefaultLookup.getColor(this, ui, "Table.focusCellForeground");
	if (col != null) {
	super.setForeground(col);
	}
	col = DefaultLookup.getColor(this, ui, "Table.focusCellBackground");
	if (col != null) {
	super.setBackground(col);
	}
	}
	} else {
	setBorder(getNoFocusBorder());
	}

	setValue(value);

	return this;
	}

	/*
	* The following methods are overridden as a performance measure to
	* to prune code-paths are often called in the case of renders
	* but which we know are unnecessary. Great care should be taken
	* when writing your own renderer to weigh the benefits and
	* drawbacks of overriding methods like these.
	*/

	/**
	* Overridden for performance reasons.
	* See the <a href="#override">Implementation Note</a>
	* for more information.
	*/
	public boolean isOpaque() {
	Color back = getBackground();
	Component p = getParent();
	if (p != null) {
	p = p.getParent();
	}

	// p should now be the JTable.
	boolean colorMatch = (back != null) && (p != null) &&
	back.equals(p.getBackground()) &&
	p.isOpaque();
	return !colorMatch && super.isOpaque();
	}

	/**
	* Overridden for performance reasons.
	* See the <a href="#override">Implementation Note</a>
	* for more information.
	*
	* @since 1.5
	*/
	public void invalidate() {}

	/**
	* Overridden for performance reasons.
	* See the <a href="#override">Implementation Note</a>
	* for more information.
	*/
	public void validate() {}

	/**
	* Overridden for performance reasons.
	* See the <a href="#override">Implementation Note</a>
	* for more information.
	*/
	public void revalidate() {}

	/**
	* Overridden for performance reasons.
	* See the <a href="#override">Implementation Note</a>
	* for more information.
	*/
	public void repaint(long tm, int x, int y, int width, int height) {}

	/**
	* Overridden for performance reasons.
	* See the <a href="#override">Implementation Note</a>
	* for more information.
	*/
	public void repaint(Rectangle r) { }

	/**
	* Overridden for performance reasons.
	* See the <a href="#override">Implementation Note</a>
	* for more information.
	*
	* @since 1.5
	*/
	public void repaint() {
	}

	/**
	* Overridden for performance reasons.
	* See the <a href="#override">Implementation Note</a>
	* for more information.
	*/
	protected void firePropertyChange(String propertyName, Object oldValue, Object newValue) {
	// Strings get interned...
	if (propertyName=="text"
	\|\| propertyName == "labelFor"
	\|\| propertyName == "displayedMnemonic"
	\|\| ((propertyName == "font" \|\| propertyName == "foreground")
	&& oldValue != newValue
	&& getClientProperty(javax.swing.plaf.basic.BasicHTML.propertyKey) != null)) {

	super.firePropertyChange(propertyName, oldValue, newValue);
	}
	}

	/**
	* Overridden for performance reasons.
	* See the <a href="#override">Implementation Note</a>
	* for more information.
	*/
	public void firePropertyChange(String propertyName, boolean oldValue, boolean newValue) { }


	/**
	* Sets the <code>String</code> object for the cell being rendered to
	* <code>value</code>.
	*
	* @param value the string value for this cell; if value is
	* <code>null</code> it sets the text value to an empty string
	* @see JLabel#setText
	*
	*/
	protected void setValue(Object value) {
	setText((value == null) ? "" : value.toString());
	}


	/**
	* A subclass of <code>DefaultTableCellRenderer</code> that
	* implements <code>UIResource</code>.
	* <code>DefaultTableCellRenderer</code> doesn't implement
	* <code>UIResource</code>
	* directly so that applications can safely override the
	* <code>cellRenderer</code> property with
	* <code>DefaultTableCellRenderer</code> subclasses.
	* <p>
	* <strong>Warning:</strong>
	* Serialized objects of this class will not be compatible with
	* future Swing releases. The current serialization support is
	* appropriate for short term storage or RMI between applications running
	* the same version of Swing. As of 1.4, support for long term storage
	* of all JavaBeans™
	* has been added to the <code>java.beans</code> package.
	* Please see {@link java.beans.XMLEncoder}.
	*/
	public static class UIResource extends DefaultTableCellRenderer
	implements javax.swing.plaf.UIResource
	{
	}

	}

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