Module java.desktop
Package java.awt

Class Desktop

java.lang.Object
java.awt.Desktop
public class Desktop extends Object
The Desktop class allows interact with various desktop capabilities.

Supported operations include:

  • launching the user-default browser to show a specified URI;
  • launching the user-default mail client with an optional mailto URI;
  • launching a registered application to open, edit or print a specified file.

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. Please see Desktop.Action for the full list of supported operations and capabilities.

An application is registered to a URI or file type. The mechanism of registering, accessing, and launching the associated application is platform-dependent.

Each operation is an action type represented by the Desktop.Action class.

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
See Also:

  • Method Details

    • getDesktop

      public static Desktop getDesktop()
      Returns the Desktop instance of the current desktop context. On some platforms the Desktop API may not be supported; use the isDesktopSupported() method to determine if the current desktop is supported.
      Returns:
      the Desktop instance
      Throws:
      HeadlessException - if GraphicsEnvironment.isHeadless() returns true
      UnsupportedOperationException - if this class is not supported on the current platform
      See Also:

    • isDesktopSupported

      public static boolean isDesktopSupported()
      Tests whether this class is supported on the current platform. If it's supported, use getDesktop() to retrieve an instance.
      Returns:
      true if this class is supported on the current platform; false otherwise
      See Also:

    • isSupported

      public boolean isSupported(Desktop.Action action)
      Tests whether an action is supported on the current platform.

      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 Desktop.Action.OPEN action. But for a specific file, there may not be an application registered to open it. In this case, isSupported(Action) may return true, but the corresponding action method will throw an IOException.

      Parameters:
      action - the specified Desktop.Action
      Returns:
      true if the specified action is supported on the current platform; false otherwise
      See Also:

    • open

      public void open(File file) throws IOException
      Launches the associated application to open the file.

      If the specified file is a directory, the file manager of the current platform is launched to open it.

      Parameters:
      file - the file to be opened with the associated application
      Throws:
      NullPointerException - if file is null
      IllegalArgumentException - if the specified file doesn't exist
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.OPEN action
      IOException - if the specified file has no associated application or the associated application fails to be launched
      SecurityException - if a security manager exists and its SecurityManager.checkRead(java.lang.String) method denies read access to the file, or it denies the AWTPermission("showWindowWithoutWarningBanner") permission, or the calling thread is not allowed to create a subprocess
      See Also:

    • edit

      public void edit(File file) throws IOException
      Launches the associated editor application and opens a file for editing.
      Parameters:
      file - the file to be opened for editing
      Throws:
      NullPointerException - if the specified file is null
      IllegalArgumentException - if the specified file doesn't exist
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.EDIT action
      IOException - if the specified file has no associated editor, or the associated application fails to be launched
      SecurityException - if a security manager exists and its SecurityManager.checkRead(java.lang.String) method denies read access to the file, or SecurityManager.checkWrite(java.lang.String) method denies write access to the file, or it denies the AWTPermission("showWindowWithoutWarningBanner") permission, or the calling thread is not allowed to create a subprocess
      See Also:

    • print

      public void print(File file) throws IOException
      Prints a file with the native desktop printing facility, using the associated application's print command.
      Parameters:
      file - the file to be printed
      Throws:
      NullPointerException - if the specified file is null
      IllegalArgumentException - if the specified file doesn't exist
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.PRINT action
      IOException - if the specified file has no associated application that can be used to print it
      SecurityException - if a security manager exists and its SecurityManager.checkRead(java.lang.String) method denies read access to the file, or its SecurityManager.checkPrintJobAccess() method denies the permission to print the file, or the calling thread is not allowed to create a subprocess

    • browse

      public void browse(URI uri) throws IOException
      Launches the default browser to display a URI. If the default browser is not able to handle the specified URI, the application registered for handling URIs of the specified type is invoked. The application is determined from the protocol and path of the URI, as defined by the URI class.
      Parameters:
      uri - the URI to be displayed in the user default browser
      Throws:
      NullPointerException - if uri is null
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.BROWSE action
      IOException - if the user default browser is not found, or it fails to be launched, or the default handler application failed to be launched
      SecurityException - if a security manager exists and it denies the AWTPermission("showWindowWithoutWarningBanner") permission, or the calling thread is not allowed to create a subprocess
      See Also:

    • mail

      public void mail() throws IOException
      Launches the mail composing window of the user default mail client.
      Throws:
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.MAIL action
      IOException - if the user default mail client is not found, or it fails to be launched
      SecurityException - if a security manager exists and it denies the AWTPermission("showWindowWithoutWarningBanner") permission, or the calling thread is not allowed to create a subprocess
      See Also:

    • mail

      public void mail(URI mailtoURI) throws IOException
      Launches the mail composing window of the user default mail client, filling the message fields specified by a mailto: URI.

      A mailto: URI can specify message fields including "to", "cc", "subject", "body", etc. See The mailto URL scheme (RFC 2368) for the mailto: URI specification details.

      Parameters:
      mailtoURI - the specified mailto: URI
      Throws:
      NullPointerException - if the specified URI is null
      IllegalArgumentException - if the URI scheme is not "mailto"
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.MAIL action
      IOException - if the user default mail client is not found or fails to be launched
      SecurityException - if a security manager exists and it denies the AWTPermission("showWindowWithoutWarningBanner") permission, or the calling thread is not allowed to create a subprocess
      See Also:

    • addAppEventListener

      public void addAppEventListener(SystemEventListener listener)
      Adds sub-types of SystemEventListener to listen for notifications from the native system. Has no effect if SystemEventListener's sub-type is unsupported on the current platform.
      Parameters:
      listener - listener
      Throws:
      SecurityException - if a security manager exists and it denies the RuntimePermission("canProcessApplicationEvents") permission
      Since:
      9
      See Also:

    • removeAppEventListener

      public void removeAppEventListener(SystemEventListener listener)
      Removes sub-types of SystemEventListener to listen for notifications from the native system. Has no effect if SystemEventListener's sub-type is unsupported on the current platform.
      Parameters:
      listener - listener
      Throws:
      SecurityException - if a security manager exists and it denies the RuntimePermission("canProcessApplicationEvents") permission
      Since:
      9
      See Also:

    • setAboutHandler

      public void setAboutHandler(AboutHandler aboutHandler)
      Installs a handler to show a custom About window for your application.

      Setting the AboutHandler to null reverts it to the default behavior.

      Parameters:
      aboutHandler - the handler to respond to the AboutHandler.handleAbout(AboutEvent) message
      Throws:
      SecurityException - if a security manager exists and it denies the RuntimePermission("canProcessApplicationEvents") permission
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.APP_ABOUT action
      Since:
      9

    • setPreferencesHandler

      public void setPreferencesHandler(PreferencesHandler preferencesHandler)
      Installs a handler to show a custom Preferences window for your application.

      Setting the PreferencesHandler to null reverts it to the default behavior

      Parameters:
      preferencesHandler - the handler to respond to the PreferencesHandler.handlePreferences(PreferencesEvent)
      Throws:
      SecurityException - if a security manager exists and it denies the RuntimePermission("canProcessApplicationEvents") permission
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.APP_PREFERENCES action
      Since:
      9

    • setOpenFileHandler

      public void setOpenFileHandler(OpenFilesHandler openFileHandler)
      Installs the handler which is notified when the application is asked to open a list of files.
      Implementation Note:
      Please note that for macOS, notifications are only sent if the Java app is a bundled application, with a CFBundleDocumentTypes array present in its Info.plist. Check the Apple Developer Documentation for more information about Info.plist.
      Parameters:
      openFileHandler - handler
      Throws:
      SecurityException - if a security manager exists and its SecurityManager.checkRead(java.lang.String) method denies read access to the files, or it denies the RuntimePermission("canProcessApplicationEvents") permission, or the calling thread is not allowed to create a subprocess
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.APP_OPEN_FILE action
      Since:
      9

    • setPrintFileHandler

      public void setPrintFileHandler(PrintFilesHandler printFileHandler)
      Installs the handler which is notified when the application is asked to print a list of files.
      Implementation Note:
      Please note that for macOS, notifications are only sent if the Java app is a bundled application, with a CFBundleDocumentTypes array present in its Info.plist. Check the Apple Developer Documentation for more information about Info.plist.
      Parameters:
      printFileHandler - handler
      Throws:
      SecurityException - if a security manager exists and its SecurityManager.checkPrintJobAccess() method denies the permission to print or it denies the RuntimePermission("canProcessApplicationEvents") permission
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.APP_PRINT_FILE action
      Since:
      9

    • setOpenURIHandler

      public void setOpenURIHandler(OpenURIHandler openURIHandler)
      Installs the handler which is notified when the application is asked to open a URL. Setting the handler to null causes all OpenURIHandler.openURI(OpenURIEvent) requests to be enqueued until another handler is set.
      Implementation Note:
      Please note that for macOS, notifications are only sent if the Java app is a bundled application, with a CFBundleDocumentTypes array present in its Info.plist. Check the Apple Developer Documentation for more information about Info.plist.
      Parameters:
      openURIHandler - handler RuntimePermission("canProcessApplicationEvents") permission, or the calling thread is not allowed to create a subprocess
      Throws:
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.APP_OPEN_URI action
      Since:
      9

    • setQuitHandler

      public void setQuitHandler(QuitHandler quitHandler)
      Installs the handler which determines if the application should quit. The handler is passed a one-shot QuitResponse which can cancel or proceed with the quit. Setting the handler to null causes all quit requests to directly perform the default QuitStrategy.
      Parameters:
      quitHandler - the handler that is called when the application is asked to quit
      Throws:
      SecurityException - if a security manager exists and it will not allow the caller to invoke System.exit or it denies the RuntimePermission("canProcessApplicationEvents") permission
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.APP_QUIT_HANDLER action
      Since:
      9

    • setQuitStrategy

      public void setQuitStrategy(QuitStrategy strategy)
      Sets the default strategy used to quit this application. The default is calling SYSTEM_EXIT_0.
      Parameters:
      strategy - the way this application should be shutdown
      Throws:
      SecurityException - if a security manager exists and it will not allow the caller to invoke System.exit or it denies the RuntimePermission("canProcessApplicationEvents") permission
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.APP_QUIT_STRATEGY action
      Since:
      9
      See Also:

    • enableSuddenTermination

      public void enableSuddenTermination()
      Enables this application to be suddenly terminated. Call this method to indicate your application's state is saved, and requires no notification to be terminated. Letting your application remain terminatable improves the user experience by avoiding re-paging in your application when it's asked to quit. Note: enabling sudden termination will allow your application to be quit without notifying your QuitHandler, or running any shutdown hooks. E.g. user-initiated Cmd-Q, logout, restart, or shutdown requests will effectively "kill -KILL" your application.
      Throws:
      SecurityException - if a security manager exists and it will not allow the caller to invoke System.exit or it denies the RuntimePermission("canProcessApplicationEvents") permission
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.APP_SUDDEN_TERMINATION action
      Since:
      9
      See Also:

    • disableSuddenTermination

      public void disableSuddenTermination()
      Prevents this application from being suddenly terminated. Call this method to indicate that your application has unsaved state, and may not be terminated without notification.
      Throws:
      SecurityException - if a security manager exists and it will not allow the caller to invoke System.exit or it denies the RuntimePermission("canProcessApplicationEvents") permission
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.APP_SUDDEN_TERMINATION action
      Since:
      9
      See Also:

    • requestForeground

      public void requestForeground(boolean allWindows)
      Requests this application to move to the foreground.
      Parameters:
      allWindows - if all windows of this application should be moved to the foreground, or only the foremost one
      Throws:
      SecurityException - if a security manager exists and it denies the RuntimePermission("canProcessApplicationEvents") permission.
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.APP_REQUEST_FOREGROUND action
      Since:
      9

    • openHelpViewer

      public void openHelpViewer()
      Opens the native help viewer application.
      Implementation Note:
      Please note that for Mac OS, it opens the native help viewer application if a Help Book has been added to the application bundler and registered in the Info.plist with CFBundleHelpBookFolder
      Throws:
      SecurityException - if a security manager exists and it denies the RuntimePermission("canProcessApplicationEvents") permission, or it denies the AWTPermission("showWindowWithoutWarningBanner") permission, or the calling thread is not allowed to create a subprocess
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.APP_HELP_VIEWER action
      Since:
      9

    • setDefaultMenuBar

      public void setDefaultMenuBar(JMenuBar menuBar)
      Sets the default menu bar to use when there are no active frames.
      Parameters:
      menuBar - to use when no other frames are active
      Throws:
      SecurityException - if a security manager exists and it denies the RuntimePermission("canProcessApplicationEvents") permission.
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.APP_MENU_BAR action
      Since:
      9

    • browseFileDirectory

      public void browseFileDirectory(File file)
      Opens a folder containing the file and selects it in a default system file manager.
      Parameters:
      file - the file
      Throws:
      SecurityException - If a security manager exists and its SecurityManager.checkRead(java.lang.String) method denies read access to the file or to its parent, or it denies the AWTPermission("showWindowWithoutWarningBanner") permission, or the calling thread is not allowed to create a subprocess
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.BROWSE_FILE_DIR action
      NullPointerException - if file is null
      IllegalArgumentException - if the specified file or its parent doesn't exist
      Since:
      9

    • moveToTrash

      public boolean moveToTrash(File file)
      Moves the specified file to the trash.
      Parameters:
      file - the file
      Returns:
      returns true if successfully moved the file to the trash.
      Throws:
      SecurityException - If a security manager exists and its SecurityManager.checkDelete(java.lang.String) method denies deletion of the file
      UnsupportedOperationException - if the current platform does not support the Desktop.Action.MOVE_TO_TRASH action
      NullPointerException - if file is null
      IllegalArgumentException - if the specified file doesn't exist
      Since:
      9