Expose files to the system?

Module Development
1

Hello!

I am trying to open a html file from an ActionPerformed of a jButton in the designer as follows:

File html = new File("Path/To/File");
if(Desktop.isDesktopSupported()){
     Desktop.getDesktop().browse(html.toURI());
}else{
     logger.info("Not supported");
}

The problem is, how can the system find the file? I have tried in the Designer’s Resource folder with no luck. I’m having the same problem with images to generate ImageIcons.

Thanks in advance,

2

Where is the file? In the module? If a resource in your module’s jar(s), you’ll have to extract the resource into a temporary file and pass that path to the external process.

3

The file would be in the module, yes. Would you mind elaborating on how to extract the temporary file?

4

You use the classloader for the class the file is alongside and open the resource as a stream:

https://docs.oracle.com/javase/8/docs/api/java/lang/ClassLoader.html#getResourceAsStream-java.lang.String-

Then I’d create and open a temporary file and use IOUtils.copy() to fill the temporary file.

5

For ImageIcon creation, I’d use findResource() to get the URL and then use the URL constructor. No need for a temporary file.

6

Okay, I think I got it. Thanks!

7

If anyone is ever wondering how to do this:

public void readAndOpenHTML()
            throws IOException {
        ClassLoader classLoader = this.getClass().getClassLoader();
        InputStream is = classLoader.getResourceAsStream("nameOftheResource.html");
        byte[] buffer = new byte[is.available()];
        is.read(buffer);
        is.close();
        Path tmpPath= Files.createTempFile("temporalName",".html");
        File html = tmpPath.toFile();
        OutputStream os = new FileOutputStream(html);
        os.write(buffer);;
        if (Desktop.isDesktopSupported()) {
            new Thread(()-> {
                try {
                    Desktop.getDesktop().browse(html.toURI());
                } catch (IOException e) {
                    //e.printStackTrace();
                    log.info("IOEX");
                    log.info(e.toString());
                }catch (Exception e){

                }
            }).start();
        } else {
            log.info("Desktop browser not suported");
        }

        os.close();

    }
1 Like
8

Consider caching the temporary file names to allow re-use if still there on future access.

9

Good point, thanks