How to copy a resource directory and all included files and sub-folders in a Jar onto another directory

问题

Is it possible to copy a resource folder, and all the files within, including all directories and sub directories therein into another directory?

What I've managed so far is to copy only one file resource, which is a CSS file:

public void addCSS() {
    Bundle bundle = FrameworkUtil.getBundle(this.getClass());
    Bundle[] bArray = bundle.getBundleContext().getBundles();
    Bundle cssBundle = null;
    for (Bundle b : bArray) {
        if (b.getSymbolicName().equals("mainscreen")) {
            cssBundle = b;
            break;
        }
    }
    Enumeration<URL> resources = null;
    try {
        resources = cssBundle.getResources("/resources/css/mainscreen.css");
    } catch (IOException e) {
            // TODO Auto-generated catch block
        e.printStackTrace();
    }
    if (resources != null) {
        URL myCSSURL = resources.nextElement();

        InputStream in;
        try {
            in = myCSSURL.openStream();
            File css = new File(this.baseDir() + "/ui/resources/css/mainscreen.css");
            try (FileOutputStream out = new FileOutputStream(css)) {
                IOUtils.copy(in, out);
            }
        } catch (IOException e) {
                // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }
}

回答1:

You need Bundle.findEntries(path,mask,recurse). This method was designed for this purpose, works beautifully with fragments as well.

void getCSSResources( List<URL> out ) 
    for ( Bundle b : context.getBundles() {
       Enumeration<URL> e = b.findEntries("myapp/resources", "*.css", true);
       while (e.hasMoreElements() {
          out.add(e.nextElement());
       }
     }
}

来源：https://stackoverflow.com/questions/36400436/how-to-copy-a-resource-directory-and-all-included-files-and-sub-folders-in-a-jar