Load containerfile in Java

Question

I have the problem in Slick that I want to load a custom containerfile(Which contains for example a few hundred images). But how in the hell do I do that? I use Slick for my game which will have animations. Slick needs for its animations a imagearray. Imagine now, if you want to display a bit complexer animation which consists of 300 images, manual loading and creating imageobjects is a pure pain in the ass process. To fix that, I have such a containerclass in mind which opens the container and returns me the images(or anything else!). Saving images back to the container would be also cool :P

So any ideas?

Thanks for any tips how to solve that in advance.

Greetings

Answer 1

If you have all your images in a directory or file directory, its pretty easy to traverse the directories and make a list or map of all the images via java's File class and some recursion. Something like...

Map <String, Image> nameToImage = new HashMap<>();
public void addDefaultImages(){
    this.addAndRecurseDirectoryOfImages(DEFAULT_IMAGE_DIRECTORY);
}

public void addAndRecurseDirectoryOfImages(String directory) {
    File folder = new File(directory);
    File[] listOfFiles = folder.listFiles();

    for (int i = 0; i < listOfFiles.length; i++) {
        if (listOfFiles[i].isFile()) {
            nameToImage.put(listOfFiles[i].getName(), new Image(directory + "/" + listOfFiles[i].getName());
        } else if (listOfFiles[i].isDirectory()) {
            addAndRecurseDirectoryOfImages(directory + "/" + listOfFiles[i].getName());
        }
    }
}

Then you can get images via the image name:

nameToImage.get(filename);

You can also add some logic to strip off the file extension.

BUT! There is a catch! If you package your application up one day, say, in a .jar file, Jar files have no concept of a file system! Meaning this won't work! In that case you'll want to generate a file that has a list of all your image locations because you won't be able to traverse directories.