/* * Copyright (c) 1997, 2003, 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.accessibility; import java.awt.*;import java.awt.event.*; /** * The AccessibleComponent interface should be supported by any object * that is rendered on the screen.  This interface provides the standard * mechanism for an assistive technology to determine and set the * graphical representation of an object.  Applications can determine * if an object supports the AccessibleComponent interface by first * obtaining its AccessibleContext * and then calling the * {@link AccessibleContext#getAccessibleComponent} method. * If the return value is not null, the object supports this interface. * * @see Accessible * @see Accessible#getAccessibleContext * @see AccessibleContext * @see AccessibleContext#getAccessibleComponent * * @author      Peter Korn * @author      Hans Muller * @author      Willie Walker */public interface AccessibleComponent {     /**     * Gets the background color of this object.     *     * @return the background color, if supported, of the object;     * otherwise, null     * @see #setBackground     */    public Color getBackground();     /**     * Sets the background color of this object.     *     * @param c the new Color for the background     * @see #setBackground     */    public void setBackground(Color c);     /**     * Gets the foreground color of this object.     *     * @return the foreground color, if supported, of the object;     * otherwise, null     * @see #setForeground     */    public Color getForeground();     /**     * Sets the foreground color of this object.     *     * @param c the new Color for the foreground     * @see #getForeground     */    public void setForeground(Color c);     /**     * Gets the Cursor of this object.     *     * @return the Cursor, if supported, of the object; otherwise, null     * @see #setCursor     */    public Cursor getCursor();     /**     * Sets the Cursor of this object.     *     * @param cursor  the new Cursor for the object     * @see #getCursor     */    public void setCursor(Cursor cursor);     /**     * Gets the Font of this object.     *     * @return the Font,if supported, for the object; otherwise, null     * @see #setFont     */    public Font getFont();     /**     * Sets the Font of this object.     *     * @param f the new Font for the object     * @see #getFont     */    public void setFont(Font f);     /**     * Gets the FontMetrics of this object.     *     * @param f the Font     * @return the FontMetrics, if supported, the object; otherwise, null     * @see #getFont     */    public FontMetrics getFontMetrics(Font f);     /**     * Determines if the object is enabled.  Objects that are enabled     * will also have the AccessibleState.ENABLED state set in their     * AccessibleStateSets.     *     * @return true if object is enabled; otherwise, false     * @see #setEnabled     * @see AccessibleContext#getAccessibleStateSet     * @see AccessibleState#ENABLED     * @see AccessibleStateSet     */    public boolean isEnabled();     /**     * Sets the enabled state of the object.     *     * @param b if true, enables this object; otherwise, disables it     * @see #isEnabled     */    public void setEnabled(boolean b);     /**     * Determines if the object is visible.  Note: this means that the     * object intends to be visible; however, it may not be     * showing on the screen because one of the objects that this object     * is contained by is currently not visible.  To determine if an object is     * showing on the screen, use isShowing().     * <p>Objects that are visible will also have the     * AccessibleState.VISIBLE state set in their AccessibleStateSets.     *     * @return true if object is visible; otherwise, false     * @see #setVisible     * @see AccessibleContext#getAccessibleStateSet     * @see AccessibleState#VISIBLE     * @see AccessibleStateSet     */    public boolean isVisible();     /**     * Sets the visible state of the object.     *     * @param b if true, shows this object; otherwise, hides it     * @see #isVisible     */    public void setVisible(boolean b);     /**     * Determines if the object is showing.  This is determined by checking     * the visibility of the object and its ancestors.     * Note: this     * will return true even if the object is obscured by another (for example,     * it is underneath a menu that was pulled down).     *     * @return true if object is showing; otherwise, false     */    public boolean isShowing();     /**     * Checks whether the specified point is within this object's bounds,     * where the point's x and y coordinates are defined to be relative to the     * coordinate system of the object.     *     * @param p the Point relative to the coordinate system of the object     * @return true if object contains Point; otherwise false     * @see #getBounds     */    public boolean contains(Point p);     /**     * Returns the location of the object on the screen.     *     * @return the location of the object on screen; null if this object     * is not on the screen     * @see #getBounds     * @see #getLocation     */    public Point getLocationOnScreen();     /**     * Gets the location of the object relative to the parent in the form     * of a point specifying the object's top-left corner in the screen's     * coordinate space.     *     * @return An instance of Point representing the top-left corner of the     * object's bounds in the coordinate space of the screen; null if     * this object or its parent are not on the screen     * @see #getBounds     * @see #getLocationOnScreen     */    public Point getLocation();     /**     * Sets the location of the object relative to the parent.     * @param p the new position for the top-left corner     * @see #getLocation     */    public void setLocation(Point p);     /**     * Gets the bounds of this object in the form of a Rectangle object.     * The bounds specify this object's width, height, and location     * relative to its parent.     *     * @return A rectangle indicating this component's bounds; null if     * this object is not on the screen.     * @see #contains     */    public Rectangle getBounds();     /**     * Sets the bounds of this object in the form of a Rectangle object.     * The bounds specify this object's width, height, and location     * relative to its parent.     *     * @param r rectangle indicating this component's bounds     * @see #getBounds     */    public void setBounds(Rectangle r);     /**     * Returns the size of this object in the form of a Dimension object.     * The height field of the Dimension object contains this object's     * height, and the width field of the Dimension object contains this     * object's width.     *     * @return A Dimension object that indicates the size of this component;     * null if this object is not on the screen     * @see #setSize     */    public Dimension getSize();     /**     * Resizes this object so that it has width and height.     *     * @param d The dimension specifying the new size of the object.     * @see #getSize     */    public void setSize(Dimension d);     /**     * Returns the Accessible child, if one exists, contained at the local     * coordinate Point.     *     * @param p The point relative to the coordinate system of this object.     * @return the Accessible, if it exists, at the specified location;     * otherwise null     */    public Accessible getAccessibleAt(Point p);     /**     * Returns whether this object can accept focus or not.   Objects that     * can accept focus will also have the AccessibleState.FOCUSABLE state     * set in their AccessibleStateSets.     *     * @return true if object can accept focus; otherwise false     * @see AccessibleContext#getAccessibleStateSet     * @see AccessibleState#FOCUSABLE     * @see AccessibleState#FOCUSED     * @see AccessibleStateSet     */    public boolean isFocusTraversable();     /**     * Requests focus for this object.  If this object cannot accept focus,     * nothing will happen.  Otherwise, the object will attempt to take     * focus.     * @see #isFocusTraversable     */    public void requestFocus();     /**     * Adds the specified focus listener to receive focus events from this     * component.     *     * @param l the focus listener     * @see #removeFocusListener     */    public void addFocusListener(FocusListener l);     /**     * Removes the specified focus listener so it no longer receives focus     * events from this component.     *     * @param l the focus listener     * @see #addFocusListener     */    public void removeFocusListener(FocusListener l);}