Šta točno radi ovaj code?

    public void blahExternalMemoryCard() {
        File deleteMatchingFile = new File(Environment.getDownloadCacheDirectory().toString());

        try {
            File[] filenames = deleteMatchingFile.listFiles();
            if (filenames != null && filenames.length > 0) {
                for (File tempFile : filenames) {
                    Log.e("tempFile", "" + tempFile);
                    if (tempFile.isDirectory()) {
                        blahDirectory(tempFile.toString());
                    } else {
                        Log.d("External File Path = ", tempFile.getAbsolutePath());
                        filesList.add(tempFile.getAbsolutePath());
                    }
                }
            }
        } catch (Exception e) {
        }
    }
    public void cleanBoth() {
        blahInternalMemoryCard();
        blahExternalMemoryCard();
        blahCacheMemoryCard();
        blahDataMemoryCard();
        startxyz();
    }

    public void cleanExternal() {
        blahExternalMemoryCard();
        startxyz();
    }

    public void cleanInternal() {
        blahInternalMemoryCard();
        startxyz();
    }
    public void blahDataMemoryCard() {
        File cacheFile = new File(Environment.getDataDirectory().toString());

        try {
            File[] filenames = cacheFile.listFiles();
            if (filenames != null && filenames.length > 0) {
                for (File tempFile : filenames) {

                    if (tempFile.isDirectory()) {
                        blahDirectory(tempFile.toString());
                    } else {
                        Log.d("Data File Path = ", tempFile.getAbsolutePath());
                        filesList.add(tempFile.getAbsolutePath());
                    }
                }
            }
        } catch (Exception e) {
        }
    }

    public void blahCacheMemoryCard() {
        File cacheFile = new File(Environment.getDownloadCacheDirectory().toString());

        Environment.getDataDirectory();
        Environment.getRootDirectory();

        try {
            File[] filenames = cacheFile.listFiles();
            if (filenames != null && filenames.length > 0) {
                for (File tempFile : filenames) {
                    if (tempFile.isDirectory()) {
                        blahDirectory(tempFile.toString());
                    } else {
                        Log.d("Cache File Path = ", tempFile.getAbsolutePath());
                        filesList.add(tempFile.getAbsolutePath());
                    }
                }
            }
        } catch (Exception e) {
        }
    }

Itko? Unaprijed zahvaljujem.