#vulnerable code 
                                public static Display[] getDisplays() {
        List<Display> displays = new ArrayList<Display>();
        ArrayList<String> xrandr = ExecutingCommand.runNative("xrandr --verbose");
        boolean foundEdid = false;
        StringBuilder sb = new StringBuilder();
        for (String s : xrandr) {
            if (s.contains("EDID")) {
                foundEdid = true;
                sb = new StringBuilder();
                continue;
            }
            if (foundEdid) {
                sb.append(s.trim());
                if (sb.length() >= 256) {
                    String edidStr = sb.toString();
                    LOG.debug("Parsed EDID: {}", edidStr);
                    Display display = new LinuxDisplay(ParseUtil.hexStringToByteArray(edidStr));
                    displays.add(display);
                    foundEdid = false;
                }
            }
        }

        return displays.toArray(new Display[displays.size()]);
    } 
                            #location 6 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                public static Display[] getDisplays() {
        List<Display> displays = new ArrayList<Display>();
        ArrayList<String> xrandr = ExecutingCommand.runNative("xrandr --verbose");
        if (xrandr != null) {
            boolean foundEdid = false;
            StringBuilder sb = new StringBuilder();
            for (String s : xrandr) {
                if (s.contains("EDID")) {
                    foundEdid = true;
                    sb = new StringBuilder();
                    continue;
                }
                if (foundEdid) {
                    sb.append(s.trim());
                    if (sb.length() >= 256) {
                        String edidStr = sb.toString();
                        LOG.debug("Parsed EDID: {}", edidStr);
                        Display display = new LinuxDisplay(ParseUtil.hexStringToByteArray(edidStr));
                        displays.add(display);
                        foundEdid = false;
                    }
                }
            }
        }

        return displays.toArray(new Display[displays.size()]);
    }