#vulnerable code 
                                private Map<String, List<AppiumDevice>> getDevices() throws Exception {
        String platform = System.getProperty(PLATFORM);
        Map<String, List<AppiumDevice>> devicesByHost = new HashMap<>();
        if (capabilityManager.getCapabilities().has("hostMachines")) {
            JSONArray hostMachines = capabilityManager.getHostMachineObject();
            for (Object hostMachine : hostMachines) {
                JSONObject hostMachineJson = (JSONObject) hostMachine;
                String machineIP = hostMachineJson.getString("machineIP");
                IAppiumManager appiumManager = AppiumManagerFactory.getAppiumManager(machineIP);
                List<Device> devices = appiumManager.getDevices(machineIP, platform);

                if (!platform.equalsIgnoreCase("android")
                        && capabilityManager.isSimulatorAppPresentInCapsJson()
                        && hostMachineJson.has("simulators")) {
                    JSONArray simulators = hostMachineJson.getJSONArray("simulators");
                    List<Device> simulatorsToBoot = getSimulatorsToBoot(
                            machineIP, simulators);
                    devices.addAll(simulatorsToBoot);
                }

                List<AppiumDevice> appiumDevices = getAppiumDevices(machineIP, devices);

                devicesByHost.put(machineIP, appiumDevices);
            }
        } else {
            throw new RuntimeException("Provide hostMachine in Caps.json for execution");
        }
        return devicesByHost;
    } 
                            #location 10 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                private Map<String, List<AppiumDevice>> getDevices() throws Exception {
        String platform = System.getenv(PLATFORM);
        Map<String, List<AppiumDevice>> devicesByHost = new HashMap<>();
        if (capabilityManager.getCapabilities().has("hostMachines")) {
            JSONArray hostMachines = capabilityManager.getHostMachineObject();
            for (Object hostMachine : hostMachines) {
                JSONObject hostMachineJson = (JSONObject) hostMachine;
                String machineIP = hostMachineJson.getString("machineIP");
                IAppiumManager appiumManager = AppiumManagerFactory.getAppiumManager(machineIP);
                List<Device> devices = appiumManager.getDevices(machineIP, platform);

                if (!platform.equalsIgnoreCase("android")
                        && capabilityManager.isSimulatorAppPresentInCapsJson()
                        && hostMachineJson.has("simulators")) {
                    JSONArray simulators = hostMachineJson.getJSONArray("simulators");
                    List<Device> simulatorsToBoot = getSimulatorsToBoot(
                            machineIP, simulators);
                    devices.addAll(simulatorsToBoot);
                }

                List<AppiumDevice> appiumDevices = getAppiumDevices(machineIP, devices);

                devicesByHost.put(machineIP, appiumDevices);
            }
        } else {
            throw new RuntimeException("Provide hostMachine in Caps.json for execution");
        }
        return devicesByHost;
    }