OK. Simple question. Maybe not so simple answer, though:
I have a file I downloaded in Java, and I know that it's a text file. Is there any way that I can use Java to open that text file in whatever the default text editor is? It has to work for all OS's, otherwise I would just make it open with Notepad.
:\ I guess that if there's no way to do this I could use JOptionPane and show the contents of the text file...
You can do that with:
java.awt.Desktop.getDesktop().edit(file);
This links to the tutorial article on java.awt.Desktop:
Java™ Standard Edition version 6 narrows the gap between performance and integration of native applications and Java applications. Along with the new system tray functionality, splash screen support, and enhanced printing for JTables , Java SE version 6 provides the Desktop API (java.awt.Desktop) API, which allows Java applications to interact with default applications associated with specific file types on the host platform.
It is cross-platform, but may not be supported everywhere. There is a method you can call to check whether the Desktop API is available, called isDesktopSupported (see the link for more explanation). I was using this API the other day to open PDFs in a Swing client.
Unfortunately there is a known bug affecting some Windows platforms (XP and 2003) that will crash the JVM. Write once, debug everywhere, as usual. Anyway, for Windows there is a nice workaround which still uses the user's preferred application:
if (System.getProperty("os.name").toLowerCase().contains("windows")) {
String cmd = "rundll32 url.dll,FileProtocolHandler " + file.getCanonicalPath();
Runtime.getRuntime().exec(cmd);
}
else {
Desktop.getDesktop().edit(file);
}
Desktop.open(File) (sometimes opens read-only) & Desktop.print(File) for slightly different actions.
Desktop.getDesktop().edit(File f);
Certainly you could configure in the text editor and use Runtime.exec to start it. But I can't think of any way to determine the default editor, especially in a system-independent fashion.
Maybe your best option is to identify which of the several most popular platforms you're on and then find a way to start the default editor on that platform. Eg, on Window you'll get the default editor if you do "start filename.txt", and I'm pretty sure there's a Linux equivalent.
