如何自定义Volley库以将发布请求作为Java对象进行获取以作为Java对象获得响应

Question

I am using framework in which I simply pass a java object. Framework methods and classes converts this object to json string and makes a post request. Also I am getting response as java object.

This same thing I wish to implement using volley library

I just want to pass Java request object and in response also want java object

Please suggest me a way how could I do that.

Thanks...

Answer 1

I have something that might help you starting. Just create your BaseRequest where you pass what you are expecting as Response. Son library takes care of converting your Json to you Java Object type.

BaseRequest

public class BaseRequest<T> extends Request<T> {

private final Class<T> resultClass;
private final Response.Listener<T> listener;
Gson gson = new Gson();

private final int REQUEST_TIMEOUT_LIMIT_SECONDS = 10; // Value in seconds

public BaseRequest(int method, String url, Class<T> resultClass, Response.Listener<T> listenerSuccess, Response.ErrorListener listenerError) {
    super(method, url, listenerError);
    this.resultClass = resultClass;
    this.listener = listenerSuccess;

    this.setRetryPolicy(new DefaultRetryPolicy(REQUEST_TIMEOUT_LIMIT_SECONDS * 1000, DefaultRetryPolicy.DEFAULT_MAX_RETRIES,
            DefaultRetryPolicy.DEFAULT_BACKOFF_MULT));

}

@Override
protected Response<T> parseNetworkResponse(NetworkResponse response) {
    try {
        String json = new String(
                response.data,
                HttpHeaderParser.parseCharset(response.headers));
        return Response.success(
                gson.fromJson(json, resultClass),
                HttpHeaderParser.parseCacheHeaders(response));
    } catch (UnsupportedEncodingException e) {
        return Response.error(new ParseError(e));
    } catch (JsonSyntaxException e) {
        return Response.error(new ParseError(e));
    }
}

@Override
protected void deliverResponse(T response) {
    listener.onResponse(response);
}
}

The method parseNetworkResponse will take care of converting your Json to Java Object type.

Now you can create a class for each Request, for example Login:

public class LoginRequest<T> extends BaseRequest<T> {

private final Gson gson = new Gson();
private final String email;
private final String password;

public LoginRequest(String email, String password, Class<T> clazz,
                    Response.Listener<T> listener, Response.ErrorListener errorListener) {

    super(Request.Method.POST, "url here...", clazz, listener, errorListener);

    this.email = email;
    this.password = password;
}


@Override
protected Map<String, String> getParams() throws AuthFailureError {
    Map<String, String> params = new HashMap<>();
    params.put("param1", email);
    params.put("param2", password);
    return params;
}
}

Finally create the call for your request (inside your activity, fragment, wherever you need):

LoginRequest request = new LoginRequest<>("aaaa@email.com", "myDummyPassword", LoginResponseModel.class, new Response.Listener<LoginResponseModel>() {
        @Override
        public void onResponse(LoginResponseModel loginResponseModel) {
            //Success
        }
    }, new BaseError(getApplicationContext()) {
        @Override
        public void onError(ErrorResponse response) {
            //Erros
        }
    });

This way you will receive the objects you want, parsed from Gson.