test.java

public class TestModule extends ReactContextBaseJavaModule {

    PinpadModule pinpadModule;


    //Constructor
    public TestModule(ReactApplicationContext reactContext) {
        super(reactContext);
        Log.d("test___2", "TestModule Constructor");
        getCurrentActivity().getApplicationContext();
    }

    //Module Name
    @Override
    public String getName() {
        return "TestModule";
    }

    @ReactMethod
    public void getDevices (Promise promise) {

        pinpadModule = new PinpadModule();

        if (pinpadModule.getDevices() == null) {
            promise.reject("Empty devices list");
        } else {
            String json = new Gson().toJson(pinpadModule.getDevices());
            promise.resolve(json);
        }
    }

}