META-INF.modules.java.desktop.classes.java.awt.MouseInfo Maven / Gradle / Ivy
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/*
* Copyright (c) 2003, 2015, 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.
*
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package java.awt;
import sun.awt.AWTPermissions;
import sun.awt.ComponentFactory;
/**
* {@code MouseInfo} provides methods for getting information about the mouse,
* such as mouse pointer location and the number of mouse buttons.
*
* @author Roman Poborchiy
* @since 1.5
*/
public class MouseInfo {
/**
* Private constructor to prevent instantiation.
*/
private MouseInfo() {
}
/**
* Returns a {@code PointerInfo} instance that represents the current
* location of the mouse pointer.
* The {@code GraphicsDevice} stored in this {@code PointerInfo}
* contains the mouse pointer. The coordinate system used for the mouse position
* depends on whether or not the {@code GraphicsDevice} is part of a virtual
* screen device.
* For virtual screen devices, the coordinates are given in the virtual
* coordinate system, otherwise they are returned in the coordinate system
* of the {@code GraphicsDevice}. See {@link GraphicsConfiguration}
* for more information about the virtual screen devices.
* On systems without a mouse, returns {@code null}.
*
* If there is a security manager, its {@code checkPermission} method
* is called with an {@code AWTPermission("watchMousePointer")}
* permission before creating and returning a {@code PointerInfo}
* object. This may result in a {@code SecurityException}.
*
* @exception HeadlessException if GraphicsEnvironment.isHeadless() returns true
* @exception SecurityException if a security manager exists and its
* {@code checkPermission} method doesn't allow the operation
* @see GraphicsConfiguration
* @see SecurityManager#checkPermission
* @see java.awt.AWTPermission
* @return location of the mouse pointer
* @since 1.5
*/
public static PointerInfo getPointerInfo() throws HeadlessException {
if (GraphicsEnvironment.isHeadless()) {
throw new HeadlessException();
}
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkPermission(AWTPermissions.WATCH_MOUSE_PERMISSION);
}
Toolkit toolkit = Toolkit.getDefaultToolkit();
Point point = new Point(0, 0);
int deviceNum = 0;
if (toolkit instanceof ComponentFactory) {
deviceNum = ((ComponentFactory) toolkit).getMouseInfoPeer().fillPointWithCoords(point);
}
GraphicsDevice[] gds = GraphicsEnvironment.getLocalGraphicsEnvironment().
getScreenDevices();
PointerInfo retval = null;
if (areScreenDevicesIndependent(gds)) {
retval = new PointerInfo(gds[deviceNum], point);
} else {
for (int i = 0; i < gds.length; i++) {
GraphicsConfiguration gc = gds[i].getDefaultConfiguration();
Rectangle bounds = gc.getBounds();
if (bounds.contains(point)) {
retval = new PointerInfo(gds[i], point);
}
}
}
return retval;
}
private static boolean areScreenDevicesIndependent(GraphicsDevice[] gds) {
for (int i = 0; i < gds.length; i++) {
Rectangle bounds = gds[i].getDefaultConfiguration().getBounds();
if (bounds.x != 0 || bounds.y != 0) {
return false;
}
}
return true;
}
/**
* Returns the number of buttons on the mouse.
* On systems without a mouse, returns {@code -1}.
* The number of buttons is obtained from the AWT Toolkit
* by requesting the {@code "awt.mouse.numButtons"} desktop property
* which is set by the underlying native platform.
*
* @exception HeadlessException if GraphicsEnvironment.isHeadless() returns true
* @return number of buttons on the mouse
* @see Toolkit#getDesktopProperty
* @since 1.5
*/
public static int getNumberOfButtons() throws HeadlessException {
if (GraphicsEnvironment.isHeadless()) {
throw new HeadlessException();
}
Object prop = Toolkit.getDefaultToolkit().
getDesktopProperty("awt.mouse.numButtons");
if (prop instanceof Integer) {
return ((Integer)prop).intValue();
}
// This should never happen.
assert false : "awt.mouse.numButtons is not an integer property";
return 0;
}
}