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	/*
	* Copyright (c) 1997, 2011, 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.plaf;

	import javax.swing.JComponent;
	import javax.swing.SwingUtilities;
	import javax.accessibility.Accessible;

	import java.awt.Component;
	import java.awt.Container;
	import java.awt.Dimension;
	import java.awt.Graphics;
	import java.awt.Insets;


	/**
	* The base class for all UI delegate objects in the Swing pluggable
	* look and feel architecture. The UI delegate object for a Swing
	* component is responsible for implementing the aspects of the
	* component that depend on the look and feel.
	* The <code>JComponent</code> class
	* invokes methods from this class in order to delegate operations
	* (painting, layout calculations, etc.) that may vary depending on the
	* look and feel installed. <b>Client programs should not invoke methods
	* on this class directly.</b>
	*
	* @see javax.swing.JComponent
	* @see javax.swing.UIManager
	*
	*/
	public abstract class ComponentUI {
	/**
	* Sole constructor. (For invocation by subclass constructors,
	* typically implicit.)
	*/
	public ComponentUI() {
	}

	/**
	* Configures the specified component appropriately for the look and feel.
	* This method is invoked when the <code>ComponentUI</code> instance is being installed
	* as the UI delegate on the specified component. This method should
	* completely configure the component for the look and feel,
	* including the following:
	* <ol>
	* <li>Install default property values for color, fonts, borders,
	* icons, opacity, etc. on the component. Whenever possible,
	* property values initialized by the client program should <i>not</i>
	* be overridden.
	* <li>Install a <code>LayoutManager</code> on the component if necessary.
	* <li>Create/add any required sub-components to the component.
	* <li>Create/install event listeners on the component.
	* <li>Create/install a <code>PropertyChangeListener</code> on the component in order
	* to detect and respond to component property changes appropriately.
	* <li>Install keyboard UI (mnemonics, traversal, etc.) on the component.
	* <li>Initialize any appropriate instance data.
	* </ol>
	* @param c the component where this UI delegate is being installed
	*
	* @see #uninstallUI
	* @see javax.swing.JComponent#setUI
	* @see javax.swing.JComponent#updateUI
	*/
	public void installUI(JComponent c) {
	}

	/**
	* Reverses configuration which was done on the specified component during
	* <code>installUI</code>. This method is invoked when this
	* <code>UIComponent</code> instance is being removed as the UI delegate
	* for the specified component. This method should undo the
	* configuration performed in <code>installUI</code>, being careful to
	* leave the <code>JComponent</code> instance in a clean state (no
	* extraneous listeners, look-and-feel-specific property objects, etc.).
	* This should include the following:
	* <ol>
	* <li>Remove any UI-set borders from the component.
	* <li>Remove any UI-set layout managers on the component.
	* <li>Remove any UI-added sub-components from the component.
	* <li>Remove any UI-added event/property listeners from the component.
	* <li>Remove any UI-installed keyboard UI from the component.
	* <li>Nullify any allocated instance data objects to allow for GC.
	* </ol>
	* @param c the component from which this UI delegate is being removed;
	* this argument is often ignored,
	* but might be used if the UI object is stateless
	* and shared by multiple components
	*
	* @see #installUI
	* @see javax.swing.JComponent#updateUI
	*/
	public void uninstallUI(JComponent c) {
	}

	/**
	* Paints the specified component appropriately for the look and feel.
	* This method is invoked from the <code>ComponentUI.update</code> method when
	* the specified component is being painted. Subclasses should override
	* this method and use the specified <code>Graphics</code> object to
	* render the content of the component.
	*
	* @param g the <code>Graphics</code> context in which to paint
	* @param c the component being painted;
	* this argument is often ignored,
	* but might be used if the UI object is stateless
	* and shared by multiple components
	*
	* @see #update
	*/
	public void paint(Graphics g, JComponent c) {
	}

	/**
	* Notifies this UI delegate that it is time to paint the specified
	* component. This method is invoked by <code>JComponent</code>
	* when the specified component is being painted.
	*
	* <p>By default this method fills the specified component with
	* its background color if its {@code opaque} property is {@code true},
	* and then immediately calls {@code paint}. In general this method need
	* not be overridden by subclasses; all look-and-feel rendering code should
	* reside in the {@code paint} method.
	*
	* @param g the <code>Graphics</code> context in which to paint
	* @param c the component being painted;
	* this argument is often ignored,
	* but might be used if the UI object is stateless
	* and shared by multiple components
	*
	* @see #paint
	* @see javax.swing.JComponent#paintComponent
	*/
	public void update(Graphics g, JComponent c) {
	if (c.isOpaque()) {
	g.setColor(c.getBackground());
	g.fillRect(0, 0, c.getWidth(),c.getHeight());
	}
	paint(g, c);
	}

	/**
	* Returns the specified component's preferred size appropriate for
	* the look and feel. If <code>null</code> is returned, the preferred
	* size will be calculated by the component's layout manager instead
	* (this is the preferred approach for any component with a specific
	* layout manager installed). The default implementation of this
	* method returns <code>null</code>.
	*
	* @param c the component whose preferred size is being queried;
	* this argument is often ignored,
	* but might be used if the UI object is stateless
	* and shared by multiple components
	*
	* @see javax.swing.JComponent#getPreferredSize
	* @see java.awt.LayoutManager#preferredLayoutSize
	*/
	public Dimension getPreferredSize(JComponent c) {
	return null;
	}

	/**
	* Returns the specified component's minimum size appropriate for
	* the look and feel. If <code>null</code> is returned, the minimum
	* size will be calculated by the component's layout manager instead
	* (this is the preferred approach for any component with a specific
	* layout manager installed). The default implementation of this
	* method invokes <code>getPreferredSize</code> and returns that value.
	*
	* @param c the component whose minimum size is being queried;
	* this argument is often ignored,
	* but might be used if the UI object is stateless
	* and shared by multiple components
	*
	* @return a <code>Dimension</code> object or <code>null</code>
	*
	* @see javax.swing.JComponent#getMinimumSize
	* @see java.awt.LayoutManager#minimumLayoutSize
	* @see #getPreferredSize
	*/
	public Dimension getMinimumSize(JComponent c) {
	return getPreferredSize(c);
	}

	/**
	* Returns the specified component's maximum size appropriate for
	* the look and feel. If <code>null</code> is returned, the maximum
	* size will be calculated by the component's layout manager instead
	* (this is the preferred approach for any component with a specific
	* layout manager installed). The default implementation of this
	* method invokes <code>getPreferredSize</code> and returns that value.
	*
	* @param c the component whose maximum size is being queried;
	* this argument is often ignored,
	* but might be used if the UI object is stateless
	* and shared by multiple components
	* @return a <code>Dimension</code> object or <code>null</code>
	*
	* @see javax.swing.JComponent#getMaximumSize
	* @see java.awt.LayoutManager2#maximumLayoutSize
	*/
	public Dimension getMaximumSize(JComponent c) {
	return getPreferredSize(c);
	}

	/**
	* Returns <code>true</code> if the specified <i>x,y</i> location is
	* contained within the look and feel's defined shape of the specified
	* component. <code>x</code> and <code>y</code> are defined to be relative
	* to the coordinate system of the specified component. Although
	* a component's <code>bounds</code> is constrained to a rectangle,
	* this method provides the means for defining a non-rectangular
	* shape within those bounds for the purpose of hit detection.
	*
	* @param c the component where the <i>x,y</i> location is being queried;
	* this argument is often ignored,
	* but might be used if the UI object is stateless
	* and shared by multiple components
	* @param x the <i>x</i> coordinate of the point
	* @param y the <i>y</i> coordinate of the point
	*
	* @see javax.swing.JComponent#contains
	* @see java.awt.Component#contains
	*/
	@SuppressWarnings("deprecation")
	public boolean contains(JComponent c, int x, int y) {
	return c.inside(x, y);
	}

	/**
	* Returns an instance of the UI delegate for the specified component.
	* Each subclass must provide its own static <code>createUI</code>
	* method that returns an instance of that UI delegate subclass.
	* If the UI delegate subclass is stateless, it may return an instance
	* that is shared by multiple components. If the UI delegate is
	* stateful, then it should return a new instance per component.
	* The default implementation of this method throws an error, as it
	* should never be invoked.
	*/
	public static ComponentUI createUI(JComponent c) {
	throw new Error("ComponentUI.createUI not implemented.");
	}

	/**
	* Returns the baseline. The baseline is measured from the top of
	* the component. This method is primarily meant for
	* <code>LayoutManager</code>s to align components along their
	* baseline. A return value less than 0 indicates this component
	* does not have a reasonable baseline and that
	* <code>LayoutManager</code>s should not align this component on
	* its baseline.
	* <p>
	* This method returns -1. Subclasses that have a meaningful baseline
	* should override appropriately.
	*
	* @param c <code>JComponent</code> baseline is being requested for
	* @param width the width to get the baseline for
	* @param height the height to get the baseline for
	* @throws NullPointerException if <code>c</code> is <code>null</code>
	* @throws IllegalArgumentException if width or height is < 0
	* @return baseline or a value < 0 indicating there is no reasonable
	* baseline
	* @see javax.swing.JComponent#getBaseline(int,int)
	* @since 1.6
	*/
	public int getBaseline(JComponent c, int width, int height) {
	if (c == null) {
	throw new NullPointerException("Component must be non-null");
	}
	if (width < 0 \|\| height < 0) {
	throw new IllegalArgumentException(
	"Width and height must be >= 0");
	}
	return -1;
	}

	/**
	* Returns an enum indicating how the baseline of he component
	* changes as the size changes. This method is primarily meant for
	* layout managers and GUI builders.
	* <p>
	* This method returns <code>BaselineResizeBehavior.OTHER</code>.
	* Subclasses that support a baseline should override appropriately.
	*
	* @param c <code>JComponent</code> to return baseline resize behavior for
	* @return an enum indicating how the baseline changes as the component
	* size changes
	* @throws NullPointerException if <code>c</code> is <code>null</code>
	* @see javax.swing.JComponent#getBaseline(int, int)
	* @since 1.6
	*/
	public Component.BaselineResizeBehavior getBaselineResizeBehavior(
	JComponent c) {
	if (c == null) {
	throw new NullPointerException("Component must be non-null");
	}
	return Component.BaselineResizeBehavior.OTHER;
	}

	/**
	* Returns the number of accessible children in the object. If all
	* of the children of this object implement <code>Accessible</code>,
	* this
	* method should return the number of children of this object.
	* UIs might wish to override this if they present areas on the
	* screen that can be viewed as components, but actual components
	* are not used for presenting those areas.
	*
	* Note: As of v1.3, it is recommended that developers call
	* <code>Component.AccessibleAWTComponent.getAccessibleChildrenCount()</code> instead
	* of this method.
	*
	* @see #getAccessibleChild
	* @return the number of accessible children in the object
	*/
	public int getAccessibleChildrenCount(JComponent c) {
	return SwingUtilities.getAccessibleChildrenCount(c);
	}

	/**
	* Returns the <code>i</code>th <code>Accessible</code> child of the object.
	* UIs might need to override this if they present areas on the
	* screen that can be viewed as components, but actual components
	* are not used for presenting those areas.
	*
	* <p>
	*
	* Note: As of v1.3, it is recommended that developers call
	* <code>Component.AccessibleAWTComponent.getAccessibleChild()</code> instead of
	* this method.
	*
	* @see #getAccessibleChildrenCount
	* @param i zero-based index of child
	* @return the <code>i</code>th <code>Accessible</code> child of the object
	*/
	public Accessible getAccessibleChild(JComponent c, int i) {
	return SwingUtilities.getAccessibleChild(c, i);
	}
	}

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