Make JAR as a standalone executable

Question

Is there a way to convert JAR lib into JAR standalone? I need to find a standalone java executable that convert PDF into TIFF and I've found these JARs: http://www.icefaces.org/JForum/posts/list/17504.page

Any ideas?

Answer 1

Easiest might be to create another Jar with a Main() entry point, and then just use the java.exe executable to run it:

e.g.

> java.exe -cp MyJarMain.jar;MyPDFJar.jar com.mydomain.MyMain myPDF.pdf

Where MyMain is a class with a Main static method.

You'll need something with a main entry point to pass in and interpret some command line arguments (myPDF.pdf in my made-up example)

Answer 2

You could do an assembly (are you using maven?) and make sure the Main-Class entry in the manifest.mf points to the main class.

Answer 3

Since there is no main-Method, you have to write one, or write a whole new class to call the class/method TiffConver.convertPDF .

The question is, how you're going to use it. From the command line, you need no executable jar. From the Gui, maybe you want to pass a file to be converted by drag and drop? Then you should take the parameter(s) passed to main as Input-PDF-Names (if they end in .pdf) and pass the names iteratively to TiffConverter, for "a.pdf b.pdf" => TiffConver.convertPDF ("a.pdf", "a.tiff"); TiffConver.convertPDF ("b.pdf", "b.tiff");

TiffCoverter will silently overwrite existing tiffs, so check that before or change the code there - this is clearly bad habit, and look out for more such things - I didn't.

/*
 * Remove target file if exists
 */
File f = new File(tif);
if (f.exists()) {
    f.delete();
}

Maybe you wan't to write a swing-wrapper, which let's you choose Files interactively to be converted. This would be a nice idee, if no filename is given.

If the user passes "a.pdf xy.tiff" you could rename the converted file to xy, as additional feature.

Without a main-class, however, a standalone jar would be magic.

However, building a native executale is almost always a bad idea. You loose portability, you don't profit from security- and performance improvements to the JVM or fixed bugs. For multiple programs you need always an independend bugfix, which you might have to manage yourself, if you don't have a package-management as most linux distros have.

---

after clearing some questions:

public static void main (String [] args) {

    if (args.length == 1 && args[0].endsWith (".pdf")) {
        String target = args[0].replaceAll (".pdf$", ".tif");
        convertPDF (args[0], target);
    }
}

This method you put into TiffConvert. It will allow you to convert a simple pdf-File, and generate a tif-File with the same basename but ending in .tif, silently overwriting an existing one of the same name.

I guess you now need to know how to start it?