ca.ucalgary.seahawk.util
Class BrowserLauncher

java.lang.Object
  ca.ucalgary.seahawk.util.BrowserLauncher

public class BrowserLauncher
extends Object

BrowserLauncher is a class that provides one static method, openURL, which opens the default web browser for the current user of the system to the given URL. It may support other protocols depending on the system -- mailto, ftp, etc. -- but that has not been rigorously tested and is not guaranteed to work.

Yes, this is platform-specific code, and yes, it may rely on classes on certain platforms that are not part of the standard JDK. What we're trying to do, though, is to take something that's frequently desirable but inherently platform-specific -- opening a default browser -- and allow programmers (you, for example) to do so without worrying about dropping into native code or doing anything else similarly evil.

Anyway, this code is completely in Java and will run on all JDK 1.1-compliant systems without modification or a need for additional libraries. All classes that are required on certain platforms to allow this to run are dynamically loaded at runtime via reflection and, if not found, will not cause this to do anything other than returning an error when opening the browser.

There are certain system requirements for this class, as it's running through Runtime.exec(), which is Java's way of making a native system call. Currently, this requires that a Macintosh have a Finder which supports the GURL event, which is true for Mac OS 8.0 and 8.1 systems that have the Internet Scripting AppleScript dictionary installed in the Scripting Additions folder in the Extensions folder (which is installed by default as far as I know under Mac OS 8.0 and 8.1), and for all Mac OS 8.5 and later systems. On Windows, it only runs under Win32 systems (Windows 95, 98, and NT 4.0, as well as later versions of all). On other systems, this drops back from the inherently platform-sensitive concept of a default browser and simply attempts to launch Netscape via a shell command.

This code is Copyright 1999-2001 by Eric Albert (ejalbert@cs.stanford.edu) and may be redistributed or modified in any form without restrictions as long as the portion of this comment from this paragraph through the end of the comment is not removed. The author requests that he be notified of any application, applet, or other binary that makes use of this code, but that's more out of curiosity than anything and is not required. This software includes no warranty. The author is not repsonsible for any loss of data or functionality or any adverse or unexpected effects of using this software.

Credits:
Steven Spencer, JavaWorld magazine (Java Tip 66)
Thanks also to Ron B. Yeh, Eric Shapiro, Ben Engber, Paul Teitlebaum, Andrea Cantatore, Larry Barowski, Trevor Bedzek, Frank Miedrich, and Ron Rabakukk

Version:

1.4b1 (Released June 20, 2001) Modified by Paul Gordon (gordonp@ucalgary.ca)

Author:

Eric Albert (ejalbert@cs.stanford.edu)

Method Summary

static Object	locateBrowser() Attempts to locate the default web browser on the local system.
static void	openURL(String url) Attempts to open the default web browser to the given URL.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

locateBrowser

public static Object locateBrowser()

Attempts to locate the default web browser on the local system. Caches results so it only locates the browser once for each use of this class per JVM instance.

Returns:

The browser for the system. Note that this may not be what you would consider to be a standard web browser; instead, it's the application that gets called to open the default web browser. In some cases, this will be a non-String object that provides the means of calling the default browser.

openURL

public static void openURL(String url)
                    throws IOException

Attempts to open the default web browser to the given URL.

Parameters:

url - The URL to open

Throws:

IOException - If the web browser could not be located or does not run