#vulnerable code 
                                public static String getPfadFlv() {
        /////////////////////
        if (!Daten.system[Konstanten.SYSTEM_PFAD_FLVSTREAMER_NR].equals("")) {
            return Daten.system[Konstanten.SYSTEM_PFAD_FLVSTREAMER_NR];
        }
        final String PFAD_LINUX_FLV = "/usr/bin/flvstreamer";
        final String PFAD_WINDOWS_FLV = "bin\\flvstreamer_win32_latest.exe";
        String pfad = "";
        if (System.getProperty("os.name").toLowerCase().contains("windows")) {
            pfad = GuiFunktionenProgramme.getPathJar() + PFAD_WINDOWS_FLV;
        } else if (System.getProperty("os.name").toLowerCase().contains("linux")) {
            pfad = PFAD_LINUX_FLV;
        }
        if (new File(pfad).exists()) {
            return pfad;
        } else {
            return "";
        }
    } 
                            #location 9 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                public static String getPfadFlv() {
        if (Daten.system[Konstanten.SYSTEM_PFAD_FLVSTREAMER_NR].equals("")) {
            new DialogOk(null, true, new PanelProgrammPfade(), "Pfade Standardprogramme").setVisible(true);
        }
        return Daten.system[Konstanten.SYSTEM_PFAD_FLVSTREAMER_NR];
    }