Returns the usable area of the screen : Swing Utilities « Swing JFC « Java






Returns the usable area of the screen

Returns the usable area of the screen
   

/*
 * $Id: Utilities.java,v 1.11 2008/10/14 22:31:46 rah003 Exp $
 *
 * Copyright 2006 Sun Microsystems, Inc., 4150 Network Circle,
 * Santa Clara, California 95054, U.S.A. All rights reserved.
 *
 * 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, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */



import java.awt.Component;
import java.awt.GraphicsConfiguration;
import java.awt.GraphicsEnvironment;
import java.awt.Insets;
import java.awt.KeyboardFocusManager;
import java.awt.Rectangle;
import java.awt.Toolkit;
import java.awt.Window;
import java.awt.event.KeyEvent;
import java.lang.ref.Reference;
import java.lang.ref.SoftReference;
import java.lang.reflect.Field;
import java.lang.reflect.Modifier;
import java.text.BreakIterator;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Locale;
import java.util.NoSuchElementException;
import java.util.StringTokenizer;
import java.util.logging.Level;
import java.util.logging.Logger;

import javax.swing.KeyStroke;
import javax.swing.SwingUtilities;

/**
 * Contribution from NetBeans: Issue #319-swingx.
 * <p>
 * 
 * PENDING: need to reconcile with OS, JVM... added as-is because needed the
 * shortcut handling to fix #
 * 
 * @author apple
 */
public class Utilities {
    private Utilities() {
    }
    
    private static final int CTRL_WILDCARD_MASK = 32768;
    private static final int ALT_WILDCARD_MASK = CTRL_WILDCARD_MASK * 2;
    
    /** Operating system is Windows NT. */
    public static final int OS_WINNT = 1 << 0;

    /** Operating system is Windows 95. */
    public static final int OS_WIN95 = OS_WINNT << 1;

    /** Operating system is Windows 98. */
    public static final int OS_WIN98 = OS_WIN95 << 1;

    /** Operating system is Solaris. */
    public static final int OS_SOLARIS = OS_WIN98 << 1;

    /** Operating system is Linux. */
    public static final int OS_LINUX = OS_SOLARIS << 1;

    /** Operating system is HP-UX. */
    public static final int OS_HP = OS_LINUX << 1;

    /** Operating system is IBM AIX. */
    public static final int OS_AIX = OS_HP << 1;

    /** Operating system is SGI IRIX. */
    public static final int OS_IRIX = OS_AIX << 1;

    /** Operating system is Sun OS. */
    public static final int OS_SUNOS = OS_IRIX << 1;

    /** Operating system is Compaq TRU64 Unix */
    public static final int OS_TRU64 = OS_SUNOS << 1;

    /** Operating system is OS/2. */
    public static final int OS_OS2 = OS_TRU64 << 2;

    /** Operating system is Mac. */
    public static final int OS_MAC = OS_OS2 << 1;

    /** Operating system is Windows 2000. */
    public static final int OS_WIN2000 = OS_MAC << 1;

    /** Operating system is Compaq OpenVMS */
    public static final int OS_VMS = OS_WIN2000 << 1;

    /**
     *Operating system is one of the Windows variants but we don't know which
     *one it is
     */
    public static final int OS_WIN_OTHER = OS_VMS << 1;

    /** Operating system is unknown. */
    public static final int OS_OTHER = OS_WIN_OTHER << 1;

    /** Operating system is FreeBSD
     * @since 4.50
     */
    public static final int OS_FREEBSD = OS_OTHER << 1;

    /** A mask for Windows platforms. */
    public static final int OS_WINDOWS_MASK = OS_WINNT | OS_WIN95 | OS_WIN98 | OS_WIN2000 | OS_WIN_OTHER;

    /** A mask for Unix platforms. */
    public static final int OS_UNIX_MASK = OS_SOLARIS | OS_LINUX | OS_HP | OS_AIX | OS_IRIX | OS_SUNOS | OS_TRU64 |
        OS_MAC | OS_FREEBSD;

    /** A height of the windows's taskbar */
    public static final int TYPICAL_WINDOWS_TASKBAR_HEIGHT = 27;

    /** A height of the Mac OS X's menu */
    private static final int TYPICAL_MACOSX_MENU_HEIGHT = 24;
    
    private static int operatingSystem = -1;
    
    /** reference to map that maps allowed key names to their values (String, Integer)
    and reference to map for mapping of values to their names */
    private static Reference<Object> namesAndValues;

    /** Get the operating system.
    * @return one of the <code>OS_*</code> constants (such as {@link #OS_WINNT})
    */
    public static int getOperatingSystem() {
        if (operatingSystem == -1) {
            String osName = System.getProperty("os.name");

            if ("Windows NT".equals(osName)) { // NOI18N
                operatingSystem = OS_WINNT;
            } else if ("Windows 95".equals(osName)) { // NOI18N
                operatingSystem = OS_WIN95;
            } else if ("Windows 98".equals(osName)) { // NOI18N
                operatingSystem = OS_WIN98;
            } else if ("Windows 2000".equals(osName)) { // NOI18N
                operatingSystem = OS_WIN2000;
            } else if (osName.startsWith("Windows ")) { // NOI18N
                operatingSystem = OS_WIN_OTHER;
            } else if ("Solaris".equals(osName)) { // NOI18N
                operatingSystem = OS_SOLARIS;
            } else if (osName.startsWith("SunOS")) { // NOI18N
                operatingSystem = OS_SOLARIS;
            }
            // JDK 1.4 b2 defines os.name for me as "Redhat Linux" -jglick
            else if (osName.endsWith("Linux")) { // NOI18N
                operatingSystem = OS_LINUX;
            } else if ("HP-UX".equals(osName)) { // NOI18N
                operatingSystem = OS_HP;
            } else if ("AIX".equals(osName)) { // NOI18N
                operatingSystem = OS_AIX;
            } else if ("Irix".equals(osName)) { // NOI18N
                operatingSystem = OS_IRIX;
            } else if ("SunOS".equals(osName)) { // NOI18N
                operatingSystem = OS_SUNOS;
            } else if ("Digital UNIX".equals(osName)) { // NOI18N
                operatingSystem = OS_TRU64;
            } else if ("OS/2".equals(osName)) { // NOI18N
                operatingSystem = OS_OS2;
            } else if ("OpenVMS".equals(osName)) { // NOI18N
                operatingSystem = OS_VMS;
            } else if (osName.equals("Mac OS X")) { // NOI18N
                operatingSystem = OS_MAC;
            } else if (osName.startsWith("Darwin")) { // NOI18N
                operatingSystem = OS_MAC;
            } else if (osName.toLowerCase(Locale.US).startsWith("freebsd")) { // NOI18N 
                operatingSystem = OS_FREEBSD;
            } else {
                operatingSystem = OS_OTHER;
            }
        }
        return operatingSystem;
    }


    /**
     * Finds out the monitor where the user currently has the input focus.
     * This method is usually used to help the client code to figure out on
     * which monitor it should place newly created windows/frames/dialogs.
     *
     * @return the GraphicsConfiguration of the monitor which currently has the
     * input focus
     */
    private static GraphicsConfiguration getCurrentGraphicsConfiguration() {
        Component focusOwner = KeyboardFocusManager.getCurrentKeyboardFocusManager().getFocusOwner();
        if (focusOwner != null) {
            Window w = SwingUtilities.getWindowAncestor(focusOwner);
            if (w != null) {
                return w.getGraphicsConfiguration();
            }
        }

        return GraphicsEnvironment.getLocalGraphicsEnvironment().getDefaultScreenDevice().getDefaultConfiguration();
    }

    /**
     * Returns the usable area of the screen where applications can place its
     * windows.  The method subtracts from the screen the area of taskbars,
     * system menus and the like.  The screen this method applies to is the one
     * which is considered current, ussually the one where the current input
     * focus is.
     *
     * @return the rectangle of the screen where one can place windows
     *
     * @since 2.5
     */
    public static Rectangle getUsableScreenBounds() {
        return getUsableScreenBounds(getCurrentGraphicsConfiguration());
    }

    /**
     * Returns the usable area of the screen where applications can place its
     * windows.  The method subtracts from the screen the area of taskbars,
     * system menus and the like.
     *
     * @param gconf the GraphicsConfiguration of the monitor
     * @return the rectangle of the screen where one can place windows
     *
     * @since 2.5
     */
    public static Rectangle getUsableScreenBounds(GraphicsConfiguration gconf) {
        if (gconf == null) {
            gconf = GraphicsEnvironment.getLocalGraphicsEnvironment().getDefaultScreenDevice().getDefaultConfiguration();
        }

        Rectangle bounds = new Rectangle(gconf.getBounds());

        String str;

        str = System.getProperty("netbeans.screen.insets"); // NOI18N

        if (str != null) {
            StringTokenizer st = new StringTokenizer(str, ", "); // NOI18N

            if (st.countTokens() == 4) {
                try {
                    bounds.y = Integer.parseInt(st.nextToken());
                    bounds.x = Integer.parseInt(st.nextToken());
                    bounds.height -= (bounds.y + Integer.parseInt(st.nextToken()));
                    bounds.width -= (bounds.x + Integer.parseInt(st.nextToken()));
                } catch (NumberFormatException ex) {
                    Logger.getAnonymousLogger().log(Level.WARNING, null, ex);
                }
            }

            return bounds;
        }

        str = System.getProperty("netbeans.taskbar.height"); // NOI18N

        if (str != null) {
            bounds.height -= Integer.getInteger(str, 0).intValue();

            return bounds;
        }

        try {
            Toolkit toolkit = Toolkit.getDefaultToolkit();
            Insets insets = toolkit.getScreenInsets(gconf);
            bounds.y += insets.top;
            bounds.x += insets.left;
            bounds.height -= (insets.top + insets.bottom);
            bounds.width -= (insets.left + insets.right);
        } catch (Exception ex) {
            Logger.getAnonymousLogger().log(Level.WARNING, null, ex);
        }

        return bounds;
    }
    

    /** Initialization of the names and values
    * @return array of two hashmaps first maps
    *   allowed key names to their values (String, Integer)
    *  and second
    * hashtable for mapping of values to their names (Integer, String)
    */
    private static synchronized HashMap[] initNameAndValues() {
        if (namesAndValues != null) {
            HashMap[] arr = (HashMap[]) namesAndValues.get();

            if (arr != null) {
                return arr;
            }
        }

        Field[] fields;
        // JW - fix Issue #353-swingx: play nicer inside sandbox.
        try {
            fields = KeyEvent.class.getDeclaredFields();
//           fields = KeyEvent.class.getFields();
        } catch (SecurityException e) { 
            // JW: need to do better? What are the use-cases where we don't have
            // any access to the fields?
            fields = new Field[0];
        }

        HashMap<String,Integer> names = new HashMap<String,Integer>(((fields.length * 4) / 3) + 5, 0.75f);
        HashMap<Integer,String> values = new HashMap<Integer,String>(((fields.length * 4) / 3) + 5, 0.75f);

        for (int i = 0; i < fields.length; i++) {
            if (Modifier.isStatic(fields[i].getModifiers())) {
                String name = fields[i].getName();

                if (name.startsWith("VK_")) { // NOI18N

                    // exclude VK
                    name = name.substring(3);

                    try {
                        int numb = fields[i].getInt(null);
                        Integer value = new Integer(numb);
                        names.put(name, value);
                        values.put(value, name);
                    } catch (IllegalArgumentException ex) {
                    } catch (IllegalAccessException ex) {
                    }
                }
            }
        }

        if (names.get("CONTEXT_MENU") == null) { // NOI18N

            Integer n = new Integer(0x20C);
            names.put("CONTEXT_MENU", n); // NOI18N
            values.put(n, "CONTEXT_MENU"); // NOI18N

            n = new Integer(0x20D);
            names.put("WINDOWS", n); // NOI18N
            values.put(n, "WINDOWS"); // NOI18N
        }

        HashMap[] arr = { names, values };

        namesAndValues = new SoftReference<Object>(arr);

        return arr;
    }

    /** Converts a Swing key stroke descriptor to a familiar Emacs-like name.
    * @param stroke key description
    * @return name of the key (e.g. <code>CS-F1</code> for control-shift-function key one)
    * @see #stringToKey
    */
    public static String keyToString(KeyStroke stroke) {
        StringBuffer sb = new StringBuffer();

        // add modifiers that must be pressed
        if (addModifiers(sb, stroke.getModifiers())) {
            sb.append('-');
        }

        HashMap[] namesAndValues = initNameAndValues();

        String c = (String) namesAndValues[1].get(new Integer(stroke.getKeyCode()));

        if (c == null) {
            sb.append(stroke.getKeyChar());
        } else {
            sb.append(c);
        }

        return sb.toString();
    }

    /** Construct a new key description from a given universal string
    * description.
    * Provides mapping between Emacs-like textual key descriptions and the
    * <code>KeyStroke</code> object used in Swing.
    * <P>
    * This format has following form:
    * <P><code>[C][A][S][M]-<em>identifier</em></code>
    * <p>Where:
    * <UL>
    * <LI> <code>C</code> stands for the Control key
    * <LI> <code>A</code> stands for the Alt key
    * <LI> <code>S</code> stands for the Shift key
    * <LI> <code>M</code> stands for the Meta key
    * </UL>
    * The format also supports two wildcard codes, to support differences in
    * platforms.  These are the preferred choices for registering keystrokes,
    * since platform conflicts will automatically be handled:
    * <UL>
    * <LI> <code>D</code> stands for the default menu accelerator - the Control
    *  key on most platforms, the Command (meta) key on Macintosh</LI>
    * <LI> <code>O</code> stands for the alternate accelerator - the Alt key on
    *  most platforms, the Ctrl key on Macintosh (Macintosh uses Alt as a
    *  secondary shift key for composing international characters - if you bind
    *  Alt-8 to an action, a mac user with a French keyboard will not be able
    *  to type the <code>[</code> character, which is a significant handicap</LI>
    * </UL>
    * If you use the wildcard characters, and specify a key which will conflict
    * with keys the operating system consumes, it will be mapped to whichever
    * choice can work - for example, on Macintosh, Command-Q is always consumed
    * by the operating system, so <code>D-Q</code> will always map to Control-Q.
    * <p>
    * Every modifier before the hyphen must be pressed.
    * <em>identifier</EM> can be any text constant from {@link KeyEvent} but
    * without the leading <code>VK_</code> characters. So {@link KeyEvent#VK_ENTER} is described as
    * <code>ENTER</code>.
    *
    * @param s the string with the description of the key
    * @return key description object, or <code>null</code> if the string does not represent any valid key
    */
    public static KeyStroke stringToKey(String s) {
        StringTokenizer st = new StringTokenizer(s.toUpperCase(Locale.ENGLISH), "-", true); // NOI18N

        int needed = 0;

        HashMap names = initNameAndValues()[0];

        int lastModif = -1;

        try {
            for (;;) {
                String el = st.nextToken();

                // required key
                if (el.equals("-")) { // NOI18N

                    if (lastModif != -1) {
                        needed |= lastModif;
                        lastModif = -1;
                    }

                    continue;
                }

                // if there is more elements
                if (st.hasMoreElements()) {
                    // the text should describe modifiers
                    lastModif = readModifiers(el);
                } else {
                    // last text must be the key code
                    Integer i = (Integer) names.get(el);
                    boolean wildcard = (needed & CTRL_WILDCARD_MASK) != 0;

                    //Strip out the explicit mask - KeyStroke won't know
                    //what to do with it
                    needed = needed & ~CTRL_WILDCARD_MASK;

                    boolean macAlt = (needed & ALT_WILDCARD_MASK) != 0;
                    needed = needed & ~ALT_WILDCARD_MASK;

                    if (i != null) {
                        //#26854 - Default accelerator should be Command on mac
                        if (wildcard) {
                            needed |= getMenuShortCutKeyMask();

                            if ((getOperatingSystem() & OS_MAC) != 0) {
                                if (!usableKeyOnMac(i.intValue(), needed)) {
                                    needed &= ~getMenuShortCutKeyMask();
                                    needed |= KeyEvent.CTRL_MASK;
                                }
                            }
                        }

                        if (macAlt) {
                            if (getOperatingSystem() == OS_MAC) {
                                needed |= KeyEvent.CTRL_MASK;
                            } else {
                                needed |= KeyEvent.ALT_MASK;
                            }
                        }

                        return KeyStroke.getKeyStroke(i.intValue(), needed);
                    } else {
                        return null;
                    }
                }
            }
        } catch (NoSuchElementException ex) {
            return null;
        }
    }
    /**
     * need to guard against headlessExceptions when testing.
     * @return the acceletor mask for shortcuts.
     */
    private static int getMenuShortCutKeyMask() {
        if (GraphicsEnvironment.isHeadless()) {
            return ((getOperatingSystem() & OS_MAC) != 0) ? 
                    KeyEvent.META_MASK : KeyEvent.CTRL_MASK;
        }
 
        return Toolkit.getDefaultToolkit().getMenuShortcutKeyMask();
    }

    private static boolean usableKeyOnMac(int key, int mask) {
        //All permutations fail for Q except ctrl
        if (key == KeyEvent.VK_Q) {
            return false;
        }

        boolean isMeta = ((mask & KeyEvent.META_MASK) != 0) || ((mask & KeyEvent.CTRL_DOWN_MASK) != 0);

        boolean isAlt = ((mask & KeyEvent.ALT_MASK) != 0) || ((mask & KeyEvent.ALT_DOWN_MASK) != 0);

        boolean isOnlyMeta = isMeta && ((mask & ~(KeyEvent.META_DOWN_MASK | KeyEvent.META_MASK)) == 0);

        //Mac OS consumes keys Command+ these keys - the app will never see
        //them, so CTRL should not be remapped for these
        if (isOnlyMeta) {
            return (key != KeyEvent.VK_H) && (key != KeyEvent.VK_SPACE) && (key != KeyEvent.VK_TAB);
        } else return !((key == KeyEvent.VK_D) && isMeta && isAlt);
    }

    /** Convert a space-separated list of Emacs-like key binding names to a list of Swing key strokes.
    * @param s the string with keys
    * @return array of key strokes, or <code>null</code> if the string description is not valid
    * @see #stringToKey
    */
    public static KeyStroke[] stringToKeys(String s) {
        StringTokenizer st = new StringTokenizer(s.toUpperCase(Locale.ENGLISH), " "); // NOI18N
        ArrayList<KeyStroke> arr = new ArrayList<KeyStroke>();

        while (st.hasMoreElements()) {
            s = st.nextToken();

            KeyStroke k = stringToKey(s);

            if (k == null) {
                return null;
            }

            arr.add(k);
        }

        return arr.toArray(new KeyStroke[arr.size()]);
    }

    /** Adds characters for modifiers to the buffer.
    * @param buf buffer to add to
    * @param modif modifiers to add (KeyEvent.XXX_MASK)
    * @return true if something has been added
    */
    private static boolean addModifiers(StringBuffer buf, int modif) {
        boolean b = false;

        if ((modif & KeyEvent.CTRL_MASK) != 0) {
            buf.append("C"); // NOI18N
            b = true;
        }

        if ((modif & KeyEvent.ALT_MASK) != 0) {
            buf.append("A"); // NOI18N
            b = true;
        }

        if ((modif & KeyEvent.SHIFT_MASK) != 0) {
            buf.append("S"); // NOI18N
            b = true;
        }

        if ((modif & KeyEvent.META_MASK) != 0) {
            buf.append("M"); // NOI18N
            b = true;
        }

        if ((modif & CTRL_WILDCARD_MASK) != 0) {
            buf.append("D");
            b = true;
        }

        if ((modif & ALT_WILDCARD_MASK) != 0) {
            buf.append("O");
            b = true;
        }

        return b;
    }

    /** Reads for modifiers and creates integer with required mask.
    * @param s string with modifiers
    * @return integer with mask
    * @exception NoSuchElementException if some letter is not modifier
    */
    private static int readModifiers(String s) throws NoSuchElementException {
        int m = 0;

        for (int i = 0; i < s.length(); i++) {
            switch (s.charAt(i)) {
            case 'C':
                m |= KeyEvent.CTRL_MASK;
                break;

            case 'A':
                m |= KeyEvent.ALT_MASK;
                break;

            case 'M':
                m |= KeyEvent.META_MASK;
                break;

            case 'S':
                m |= KeyEvent.SHIFT_MASK;
                break;

            case 'D':
                m |= CTRL_WILDCARD_MASK;
                break;

            case 'O':
                m |= ALT_WILDCARD_MASK;
                break;

            default:
                throw new NoSuchElementException(s);
            }
        }

        return m;
    }
    
    
}

   
    
    
  








Related examples in the same category

1.Swing Utilities getWindowAncestor
2.Swing invoke and wait
3.Swing invoke later
4.Getting the JFrame of a Component
5.Convert a coordinate relative to a component's bounds to screen coordinates
6.Convert a coordinate on a screen to a coordinate relative to a component's bounds
7.Handle long-running tasks in a Swing application
8.Swing worker Example
9.Center that window on the given desktop.
10.Converts a Swing key stroke descriptor to a familiar Emacs-like nameConverts a Swing key stroke descriptor to a familiar Emacs-like name
11.Get Owning Frame for Component
12.Get Screen Bounds For
13.Get Top Frame
14.Get Top Level Ancestor
15.Change the sizes of all the passed buttons to be the size of the largest one.
16.Using SwingUtilities.updateComponentTreeUI to update UI by platform settingsUsing SwingUtilities.updateComponentTreeUI to update UI by platform settings
17.Repaints the parent of the given component.
18.Gets the root pane of the given component.
19.Gets the root pane of the window.
20.Gets the layered pane of the window of the given component.
21.Gets the content pane of the given window.
22.Verifies if the given point is visible on the screen.
23.Determines if the component is visible in its window at the given screen location.