/* * Copyright (c) 2005, 2006, 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 java.awt; import java.io.File;import java.io.IOException;import java.net.URISyntaxException;import java.net.URI;import java.net.URL;import java.net.MalformedURLException;import java.awt.AWTPermission;import java.awt.GraphicsEnvironment;import java.awt.HeadlessException;import java.awt.peer.DesktopPeer;import sun.awt.SunToolkit;import sun.awt.HeadlessToolkit;import java.io.FilePermission;import sun.security.util.SecurityConstants; /** * The {@code Desktop} class allows a Java application to launch * associated applications registered on the native desktop to handle * a {@link java.net.URI} or a file. * * <p> Supported operations include: * <ul> *   <li>launching the user-default browser to show a specified *       URI;</li> *   <li>launching the user-default mail client with an optional *       {@code mailto} URI;</li> *   <li>launching a registered application to open, edit or print a *       specified file.</li> * </ul> * * <p> This class provides methods corresponding to these * operations. The methods look for the associated application * registered on the current platform, and launch it to handle a URI * or file. If there is no associated application or the associated * application fails to be launched, an exception is thrown. * * <p> An application is registered to a URI or file type; for * example, the {@code "sxi"} file extension is typically registered * to StarOffice.  The mechanism of registering, accessing, and * launching the associated application is platform-dependent. * * <p> Each operation is an action type represented by the {@link * Desktop.Action} class. * * <p> Note: when some action is invoked and the associated * application is executed, it will be executed on the same system as * the one on which the Java application was launched. * * @since 1.6 * @author Armin Chen * @author George Zhang */public class Desktop {     /**     * Represents an action type.  Each platform supports a different     * set of actions.  You may use the {@link Desktop#isSupported}     * method to determine if the given action is supported by the     * current platform.     * @see java.awt.Desktop#isSupported(java.awt.Desktop.Action)     * @since 1.6     */    public static enum Action {        /**         * Represents an "open" action.         * @see Desktop#open(java.io.File)         */        OPEN,        /**         * Represents an "edit" action.         * @see Desktop#edit(java.io.File)         */        EDIT,        /**         * Represents a "print" action.         * @see Desktop#print(java.io.File)         */        PRINT,        /**         * Represents a "mail" action.         * @see Desktop#mail()         * @see Desktop#mail(java.net.URI)         */        MAIL,        /**         * Represents a "browse" action.         * @see Desktop#browse(java.net.URI)         */        BROWSE    };     private DesktopPeer peer;     /**     * Suppresses default constructor for noninstantiability.     */    private Desktop() {        peer = Toolkit.getDefaultToolkit().createDesktopPeer(this);    }     /**     * Returns the <code>Desktop</code> instance of the current     * browser context.  On some platforms the Desktop API may not be     * supported; use the {@link #isDesktopSupported} method to     * determine if the current desktop is supported.     * @return the Desktop instance of the current browser context     * @throws HeadlessException if {@link     * GraphicsEnvironment#isHeadless()} returns {@code true}     * @throws UnsupportedOperationException if this class is not     * supported on the current platform     * @see #isDesktopSupported()     * @see java.awt.GraphicsEnvironment#isHeadless     */    public static synchronized Desktop getDesktop(){        if (GraphicsEnvironment.isHeadless()) throw new HeadlessException();        if (!Desktop.isDesktopSupported()) {            throw new UnsupportedOperationException("Desktop API is not " +                                                    "supported on the current platform");        }         sun.awt.AppContext context = sun.awt.AppContext.getAppContext();        Desktop desktop = (Desktop)context.get(Desktop.class);         if (desktop == null) {            desktop = new Desktop();            context.put(Desktop.class, desktop);        }         return desktop;    }     /**     * Tests whether this class is supported on the current platform.     * If it's supported, use {@link #getDesktop()} to retrieve an     * instance.     *     * @return <code>true</code> if this class is supported on the     *         current platform; <code>false</code> otherwise     * @see #getDesktop()     */    public static boolean isDesktopSupported(){        Toolkit defaultToolkit = Toolkit.getDefaultToolkit();        if (defaultToolkit instanceof SunToolkit) {            return ((SunToolkit)defaultToolkit).isDesktopSupported();        }        return false;    }     /**     * Tests whether an action is supported on the current platform.     *     * <p>Even when the platform supports an action, a file or URI may     * not have a registered application for the action.  For example,     * most of the platforms support the {@link Desktop.Action#OPEN}     * action.  But for a specific file, there may not be an     * application registered to open it.  In this case, {@link     * #isSupported} may return {@code true}, but the corresponding     * action method will throw an {@link IOException}.     *     * @param action the specified {@link Action}     * @return <code>true</code> if the specified action is supported on     *         the current platform; <code>false</code> otherwise     * @see Desktop.Action     */    public boolean isSupported(Action action) {        return peer.isSupported(action);    }     /**     * Checks if the file is a valid file and readable.     *     * @throws SecurityException If a security manager exists and its     *         {@link SecurityManager#checkRead(java.lang.String)} method     *         denies read access to the file     * @throws NullPointerException if file is null     * @throws IllegalArgumentException if file doesn't exist     */    private static void checkFileValidation(File file){        if (file == null) throw new NullPointerException("File must not be null");         if (!file.exists()) {            throw new IllegalArgumentException("The file: "                                               + file.getPath() + " doesn't exist.");        }         file.canRead();    }     /**     * Checks if the action type is supported.     *     * @param actionType the action type in question     * @throws UnsupportedOperationException if the specified action type is not     *         supported on the current platform     */    private void checkActionSupport(Action actionType){        if (!isSupported(actionType)) {            throw new UnsupportedOperationException("The " + actionType.name()                                                    + " action is not supported on the current platform!");        }    }      /**     *  Calls to the security manager's <code>checkPermission</code> method with     *  an <code>AWTPermission("showWindowWithoutWarningBanner")</code>     *  permission.     */    private void checkAWTPermission(){        SecurityManager sm = System.getSecurityManager();        if (sm != null) {            sm.checkPermission(new AWTPermission(                                   "showWindowWithoutWarningBanner"));        }    }     /**     * Launches the associated application to open the file.     *     * <p> If the specified file is a directory, the file manager of     * the current platform is launched to open it.     *     * @param file the file to be opened with the associated application     * @throws NullPointerException if {@code file} is {@code null}     * @throws IllegalArgumentException if the specified file doesn't     * exist     * @throws UnsupportedOperationException if the current platform     * does not support the {@link Desktop.Action#OPEN} action     * @throws IOException if the specified file has no associated     * application or the associated application fails to be launched     * @throws SecurityException if a security manager exists and its     * {@link java.lang.SecurityManager#checkRead(java.lang.String)}     * method denies read access to the file, or it denies the     * <code>AWTPermission("showWindowWithoutWarningBanner")</code>     * permission, or the calling thread is not allowed to create a     * subprocess     * @see java.awt.AWTPermission     */    public void open(File file) throws IOException {        checkAWTPermission();        checkExec();        checkActionSupport(Action.OPEN);        checkFileValidation(file);         peer.open(file);    }     /**     * Launches the associated editor application and opens a file for     * editing.     *     * @param file the file to be opened for editing     * @throws NullPointerException if the specified file is {@code null}     * @throws IllegalArgumentException if the specified file doesn't     * exist     * @throws UnsupportedOperationException if the current platform     * does not support the {@link Desktop.Action#EDIT} action     * @throws IOException if the specified file has no associated     * editor, or the associated application fails to be launched     * @throws SecurityException if a security manager exists and its     * {@link java.lang.SecurityManager#checkRead(java.lang.String)}     * method denies read access to the file, or {@link     * java.lang.SecurityManager#checkWrite(java.lang.String)} method     * denies write access to the file, or it denies the     * <code>AWTPermission("showWindowWithoutWarningBanner")</code>     * permission, or the calling thread is not allowed to create a     * subprocess     * @see java.awt.AWTPermission     */    public void edit(File file) throws IOException {        checkAWTPermission();        checkExec();        checkActionSupport(Action.EDIT);        file.canWrite();        checkFileValidation(file);         peer.edit(file);    }     /**     * Prints a file with the native desktop printing facility, using     * the associated application's print command.     *     * @param file the file to be printed     * @throws NullPointerException if the specified file is {@code     * null}     * @throws IllegalArgumentException if the specified file doesn't     * exist     * @throws UnsupportedOperationException if the current platform     *         does not support the {@link Desktop.Action#PRINT} action     * @throws IOException if the specified file has no associated     * application that can be used to print it     * @throws SecurityException if a security manager exists and its     * {@link java.lang.SecurityManager#checkRead(java.lang.String)}     * method denies read access to the file, or its {@link     * java.lang.SecurityManager#checkPrintJobAccess()} method denies     * the permission to print the file, or the calling thread is not     * allowed to create a subprocess     */    public void print(File file) throws IOException {        checkExec();        SecurityManager sm = System.getSecurityManager();        if (sm != null) {            sm.checkPrintJobAccess();        }        checkActionSupport(Action.PRINT);        checkFileValidation(file);         peer.print(file);    }     /**     * Launches the default browser to display a {@code URI}.     * If the default browser is not able to handle the specified     * {@code URI}, the application registered for handling     * {@code URIs} of the specified type is invoked. The application     * is determined from the protocol and path of the {@code URI}, as     * defined by the {@code URI} class.     * <p>     * If the calling thread does not have the necessary permissions,     * and this is invoked from within an applet,     * {@code AppletContext.showDocument()} is used. Similarly, if the calling     * does not have the necessary permissions, and this is invoked from within     * a Java Web Started application, {@code BasicService.showDocument()}     * is used.     *     * @param uri the URI to be displayed in the user default browser     * @throws NullPointerException if {@code uri} is {@code null}     * @throws UnsupportedOperationException if the current platform     * does not support the {@link Desktop.Action#BROWSE} action     * @throws IOException if the user default browser is not found,     * or it fails to be launched, or the default handler application     * failed to be launched     * @throws SecurityException if a security manager exists and it     * denies the     * <code>AWTPermission("showWindowWithoutWarningBanner")</code>     * permission, or the calling thread is not allowed to create a     * subprocess; and not invoked from within an applet or Java Web Started     * application     * @throws IllegalArgumentException if the necessary permissions     * are not available and the URI can not be converted to a {@code URL}     * @see java.net.URI     * @see java.awt.AWTPermission     * @see java.applet.AppletContext     */    public void browse(URI uri) throws IOException {        SecurityException securityException = null;        try {            checkAWTPermission();            checkExec();        } catch (SecurityException e) {            securityException = e;        }        checkActionSupport(Action.BROWSE);        if (uri == null) {            throw new NullPointerException();        }        if (securityException == null) {            peer.browse(uri);            return;        }         // Calling thread doesn't have necessary priviledges.        // Delegate to DesktopBrowse so that it can work in        // applet/webstart.        URL url = null;        try {            url = uri.toURL();        } catch (MalformedURLException e) {            throw new IllegalArgumentException("Unable to convert URI to URL", e);        }        sun.awt.DesktopBrowse db = sun.awt.DesktopBrowse.getInstance();        if (db == null) {            // Not in webstart/applet, throw the exception.            throw securityException;        }        db.browse(url);    }     /**     * Launches the mail composing window of the user default mail     * client.     *     * @throws UnsupportedOperationException if the current platform     * does not support the {@link Desktop.Action#MAIL} action     * @throws IOException if the user default mail client is not     * found, or it fails to be launched     * @throws SecurityException if a security manager exists and it     * denies the     * <code>AWTPermission("showWindowWithoutWarningBanner")</code>     * permission, or the calling thread is not allowed to create a     * subprocess     * @see java.awt.AWTPermission     */    public void mail() throws IOException {        checkAWTPermission();        checkExec();        checkActionSupport(Action.MAIL);        URI mailtoURI = null;        try{            mailtoURI = new URI("mailto:?");            peer.mail(mailtoURI);        } catch (URISyntaxException e){            // won't reach here.        }    }     /**     * Launches the mail composing window of the user default mail     * client, filling the message fields specified by a {@code     * mailto:} URI.     *     * <p> A <code>mailto:</code> URI can specify message fields     * including <i>"to"</i>, <i>"cc"</i>, <i>"subject"</i>,     * <i>"body"</i>, etc.  See <a     * href="http://www.ietf.org/rfc/rfc2368.txt">The mailto URL     * scheme (RFC 2368)</a> for the {@code mailto:} URI specification     * details.     *     * @param mailtoURI the specified {@code mailto:} URI     * @throws NullPointerException if the specified URI is {@code     * null}     * @throws IllegalArgumentException if the URI scheme is not     *         <code>"mailto"</code>     * @throws UnsupportedOperationException if the current platform     * does not support the {@link Desktop.Action#MAIL} action     * @throws IOException if the user default mail client is not     * found or fails to be launched     * @throws SecurityException if a security manager exists and it     * denies the     * <code>AWTPermission("showWindowWithoutWarningBanner")</code>     * permission, or the calling thread is not allowed to create a     * subprocess     * @see java.net.URI     * @see java.awt.AWTPermission     */    public  void mail(URI mailtoURI) throws IOException {        checkAWTPermission();        checkExec();        checkActionSupport(Action.MAIL);        if (mailtoURI == null) throw new NullPointerException();         if (!"mailto".equalsIgnoreCase(mailtoURI.getScheme())) {            throw new IllegalArgumentException("URI scheme is not \"mailto\"");        }         peer.mail(mailtoURI);    }     private void checkExec() throws SecurityException {        SecurityManager sm = System.getSecurityManager();        if (sm != null) {            sm.checkPermission(new FilePermission("<<ALL FILES>>",                                                  SecurityConstants.FILE_EXECUTE_ACTION));        }    }}