Open a file with an external application on Java

Question

How do you open a file from a java application when you do not know which application the file is associated with. Also, because I'm using Java, I'd prefer a platform independent solution.

Answer 1

You could hack something together with a bat file on Windows and equivalent on Unix, but that wouldn't be that fun.

I think your best bet would be the JDesktop Integration Components (JDIC). In particular, the Desktop class has exactly the method you're looking for.

EDIT: Apparently, I'm behind the times because this has been integrated into Java 1.6. In any case, if you're working in an earlier Java, it may still be useful.

Answer 2

With JDK1.6, the java.awt.Desktop class can be useful.

public static void open(File document) throws IOException {
    Desktop dt = Desktop.getDesktop();
    dt.open(document);
}

ref : http://java.sun.com/javase/6/docs/api/java/awt/Desktop.html

Answer 3

Open the file to read from within the application? Or open the application that is responsible for that file type?

Answer 4

File file
Desktop.getDesktop().open( file );

Since Java 1.6

Previous to that you could check this question

Sumary

It would look something like this:

Runtime.getRuntime().exec( getCommand( file ) );

public String getCommand( String file ){ 
    // Depending on the platform could be
    //String.format("gnome-open %s", fileName)
    //String.format("open %s", fileName)
    //String.format("cmd /c start %s", fileName)
    // etc. 
}