Is there a way to get a file from res folder with ClassLoader and getClass() method

Question

I have the loadImage function for getting images. It only does not work when I am trying to get the file from the getFile() function.

public BufferedImage loadImage(String img) {
    BufferedImage bimg = null;
    try {
        bimg = ImageIO.read(new File("res/" + img));
    } catch (Exception e1) {
        try {
            bimg = ImageIO.read(ClassLoader.getSystemResource("res/" + img));
        } catch (Exception e2) {
            try {
                bimg = ImageIO.read(getClass().getResource("res/" + img));
            } catch (Exception e3) {
                System.out.println("Cannot load image: " + img);
            }
        }
    }
    return bimg;
}

I have tried using the following function:

public File getFile(String file) {
    File f = null;
    try {
        f = new File("res/" + file);
    } catch (Exception e1) {
        try {
             f = new File(ClassLoader.getSystemResource("res/" + file).getFile());
        } catch (Exception e2) {
            try {
                f = new File(getClass().getResource("res/" + file).getFile());
            } catch (Exception e3) {
                System.out.println("Cannot load File: " + file);
            }
        }
    }
    return f;
}

These functions are in a jar lib and my other project want to get a file from the jar lib.

This is in my project trying to get config.cfg file from the jar lib

File file = files.getFile("config.cfg");

I have opened the jar and checked, if that the file exists inside the jar.

Answer 1

You can use the Class.getResourceAsStream(String name). For example, if you have "/data/config.cfg" in the jar file, then you can open that file for reading using the following line:

InputStream is = this.getClass().getResourceAsStream("/data/config.cfg");