/*
* Copyright (c) 2005, 2018, Oracle and/or its affiliates. All rights reserved.
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*
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*/
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.
exists()) {
throw new
IllegalArgumentException("The file: "
+
file.
getPath() + " doesn't exist.");
}
}
/**
* 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 {
file = new
File(
file.
getPath());
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 {
file = new
File(
file.
getPath());
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 {
file = new
File(
file.
getPath());
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));
}
}
}