Call multiple asynchronous HTTP requests and wait for the result
1
I have a Repository class which looks like this:
public class Repository extends Observable {
private List<Event> events;
private List<Article> articles;
private List<Article> sportArticles;
private List<Article> fitnessArticles;
private List<Article> governmentArticles;
private Article mainArticle;
private Configuration config;
public Repository() {
loadRepository();
}
private void loadRepository() {
ExecutorService exService = Executors.newSingleThreadExecutor();
exService.submit(new Runnable() {
@Override
public void run() {
try {
OkHttpClient client = new OkHttpClient.Builder().connectTimeout(15, TimeUnit.SECONDS).build();
final Gson gson = new GsonBuilder().registerTypeHierarchyAdapter(Calendar.class, new CalendarGson()).create();
final AtomicBoolean error = new AtomicBoolean();
final CountDownLatch latch = new CountDownLatch(7);
Request.Builder requestbuilder = new Request.Builder();
Request articlesRequest = requestbuilder.url("https://apiurlarticles").build();
Request eventsRequest = requestbuilder.url("https://apiurlevents").build();
Request sportArticlesRequest = requestbuilder.url("https://apiurlsports").build();
Request fitnessArticlesRequest = requestbuilder.url("https://apiurlfitness").build();
Request governmentArticlesrequest = requestbuilder.url("https://apiurlgovernment").build();
Request mainArticleRequest = requestbuilder.url("https://apiurlmain").build();
Request configurationRequest = requestbuilder.url("https://apiurlconfig").build();
//Article Request
client.newCall(articlesRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
articles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Events Request
client.newCall(eventsrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
events = gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Sports Request
client.newCall(sportArticlesRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
sportArticles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Fitness Request
client.newCall(fitnessArticlesRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
fitnessArticles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Government Request
client.newCall(governmentArticlesrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
governmentArticles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Main Article Request
client.newCall(mainArticleRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
mainArticle = gson.fromJson(body.string(), new TypeToken<Article>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Configuration request
client.newCall(configurationRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
config = gson.fromJson(body.string(), new TypeToken<Configuration>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
try {
latch.await();
} catch (InterruptedException e) {
error.set(true);
}
notifyObservers(error.get() ? HTTPRequestStatus.HTTPERROR : HTTPRequestStatus.OK);
} catch (KeyManagementException | NoSuchAlgorithmException | KeyStoreException e) {
notifyObservers(HTTPRequestStatus.TLSERROR);
}
}
});
exService.shutdown();
}
}
This code calls several HTTP requests asynchronously and wait for all of them to conclude. If any request fails it notifies with an error, otherwise success. These requests returns JSON and I parse them using Gson.
For simplicity I have only showed two requests, however I want to refactor this code for any number of requests. There is a lot of similar code, but I can't figure a way to refactor it. I have already tried to create a custom Callback class however I can't figure a way to pass a Type and return the parsed value.
How would you approach this one?
java android gson
asked Dec 27 '18 at 17:51
Exprove
1063
New contributor
Exprove is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
1
I have a Repository class which looks like this:
public class Repository extends Observable {
private List<Event> events;
private List<Article> articles;
private List<Article> sportArticles;
private List<Article> fitnessArticles;
private List<Article> governmentArticles;
private Article mainArticle;
private Configuration config;
public Repository() {
loadRepository();
}
private void loadRepository() {
ExecutorService exService = Executors.newSingleThreadExecutor();
exService.submit(new Runnable() {
@Override
public void run() {
try {
OkHttpClient client = new OkHttpClient.Builder().connectTimeout(15, TimeUnit.SECONDS).build();
final Gson gson = new GsonBuilder().registerTypeHierarchyAdapter(Calendar.class, new CalendarGson()).create();
final AtomicBoolean error = new AtomicBoolean();
final CountDownLatch latch = new CountDownLatch(7);
Request.Builder requestbuilder = new Request.Builder();
Request articlesRequest = requestbuilder.url("https://apiurlarticles").build();
Request eventsRequest = requestbuilder.url("https://apiurlevents").build();
Request sportArticlesRequest = requestbuilder.url("https://apiurlsports").build();
Request fitnessArticlesRequest = requestbuilder.url("https://apiurlfitness").build();
Request governmentArticlesrequest = requestbuilder.url("https://apiurlgovernment").build();
Request mainArticleRequest = requestbuilder.url("https://apiurlmain").build();
Request configurationRequest = requestbuilder.url("https://apiurlconfig").build();
//Article Request
client.newCall(articlesRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
articles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Events Request
client.newCall(eventsrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
events = gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Sports Request
client.newCall(sportArticlesRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
sportArticles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Fitness Request
client.newCall(fitnessArticlesRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
fitnessArticles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Government Request
client.newCall(governmentArticlesrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
governmentArticles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Main Article Request
client.newCall(mainArticleRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
mainArticle = gson.fromJson(body.string(), new TypeToken<Article>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Configuration request
client.newCall(configurationRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
config = gson.fromJson(body.string(), new TypeToken<Configuration>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
try {
latch.await();
} catch (InterruptedException e) {
error.set(true);
}
notifyObservers(error.get() ? HTTPRequestStatus.HTTPERROR : HTTPRequestStatus.OK);
} catch (KeyManagementException | NoSuchAlgorithmException | KeyStoreException e) {
notifyObservers(HTTPRequestStatus.TLSERROR);
}
}
});
exService.shutdown();
}
}
This code calls several HTTP requests asynchronously and wait for all of them to conclude. If any request fails it notifies with an error, otherwise success. These requests returns JSON and I parse them using Gson.
For simplicity I have only showed two requests, however I want to refactor this code for any number of requests. There is a lot of similar code, but I can't figure a way to refactor it. I have already tried to create a custom Callback class however I can't figure a way to pass a Type and return the parsed value.
How would you approach this one?
java android gson
asked Dec 27 '18 at 17:51
Exprove
1063
New contributor
Exprove is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
2
Simplicity isn't usually the way to go here. I recommend you show the rest of your code. You might get different answers based on the less "simple" code than you would with what you currently have. Also please change the title to describe What your code Does as apposed to your goal. (Almost everyone wants to refactor their code.)
– bruglesco
Dec 27 '18 at 19:36
@bruglesco The difference between this code and the actual one is that there are like 10RequestObjects and 10client.newCalls(request), should I include them anyway?
– Exprove
Dec 27 '18 at 20:55
Yes. You should.
– bruglesco
Dec 27 '18 at 21:17
add a comment |
1
1
1
I have a Repository class which looks like this:
public class Repository extends Observable {
private List<Event> events;
private List<Article> articles;
private List<Article> sportArticles;
private List<Article> fitnessArticles;
private List<Article> governmentArticles;
private Article mainArticle;
private Configuration config;
public Repository() {
loadRepository();
}
private void loadRepository() {
ExecutorService exService = Executors.newSingleThreadExecutor();
exService.submit(new Runnable() {
@Override
public void run() {
try {
OkHttpClient client = new OkHttpClient.Builder().connectTimeout(15, TimeUnit.SECONDS).build();
final Gson gson = new GsonBuilder().registerTypeHierarchyAdapter(Calendar.class, new CalendarGson()).create();
final AtomicBoolean error = new AtomicBoolean();
final CountDownLatch latch = new CountDownLatch(7);
Request.Builder requestbuilder = new Request.Builder();
Request articlesRequest = requestbuilder.url("https://apiurlarticles").build();
Request eventsRequest = requestbuilder.url("https://apiurlevents").build();
Request sportArticlesRequest = requestbuilder.url("https://apiurlsports").build();
Request fitnessArticlesRequest = requestbuilder.url("https://apiurlfitness").build();
Request governmentArticlesrequest = requestbuilder.url("https://apiurlgovernment").build();
Request mainArticleRequest = requestbuilder.url("https://apiurlmain").build();
Request configurationRequest = requestbuilder.url("https://apiurlconfig").build();
//Article Request
client.newCall(articlesRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
articles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Events Request
client.newCall(eventsrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
events = gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Sports Request
client.newCall(sportArticlesRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
sportArticles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Fitness Request
client.newCall(fitnessArticlesRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
fitnessArticles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Government Request
client.newCall(governmentArticlesrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
governmentArticles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Main Article Request
client.newCall(mainArticleRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
mainArticle = gson.fromJson(body.string(), new TypeToken<Article>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Configuration request
client.newCall(configurationRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
config = gson.fromJson(body.string(), new TypeToken<Configuration>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
try {
latch.await();
} catch (InterruptedException e) {
error.set(true);
}
notifyObservers(error.get() ? HTTPRequestStatus.HTTPERROR : HTTPRequestStatus.OK);
} catch (KeyManagementException | NoSuchAlgorithmException | KeyStoreException e) {
notifyObservers(HTTPRequestStatus.TLSERROR);
}
}
});
exService.shutdown();
}
}
This code calls several HTTP requests asynchronously and wait for all of them to conclude. If any request fails it notifies with an error, otherwise success. These requests returns JSON and I parse them using Gson.
For simplicity I have only showed two requests, however I want to refactor this code for any number of requests. There is a lot of similar code, but I can't figure a way to refactor it. I have already tried to create a custom Callback class however I can't figure a way to pass a Type and return the parsed value.
How would you approach this one?
java android gson
asked Dec 27 '18 at 17:51
Exprove
1063
New contributor
Exprove is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
I have a Repository class which looks like this:
public class Repository extends Observable {
private List<Event> events;
private List<Article> articles;
private List<Article> sportArticles;
private List<Article> fitnessArticles;
private List<Article> governmentArticles;
private Article mainArticle;
private Configuration config;
public Repository() {
loadRepository();
}
private void loadRepository() {
ExecutorService exService = Executors.newSingleThreadExecutor();
exService.submit(new Runnable() {
@Override
public void run() {
try {
OkHttpClient client = new OkHttpClient.Builder().connectTimeout(15, TimeUnit.SECONDS).build();
final Gson gson = new GsonBuilder().registerTypeHierarchyAdapter(Calendar.class, new CalendarGson()).create();
final AtomicBoolean error = new AtomicBoolean();
final CountDownLatch latch = new CountDownLatch(7);
Request.Builder requestbuilder = new Request.Builder();
Request articlesRequest = requestbuilder.url("https://apiurlarticles").build();
Request eventsRequest = requestbuilder.url("https://apiurlevents").build();
Request sportArticlesRequest = requestbuilder.url("https://apiurlsports").build();
Request fitnessArticlesRequest = requestbuilder.url("https://apiurlfitness").build();
Request governmentArticlesrequest = requestbuilder.url("https://apiurlgovernment").build();
Request mainArticleRequest = requestbuilder.url("https://apiurlmain").build();
Request configurationRequest = requestbuilder.url("https://apiurlconfig").build();
//Article Request
client.newCall(articlesRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
articles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Events Request
client.newCall(eventsrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
events = gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Sports Request
client.newCall(sportArticlesRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
sportArticles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Fitness Request
client.newCall(fitnessArticlesRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
fitnessArticles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Government Request
client.newCall(governmentArticlesrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
governmentArticles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Main Article Request
client.newCall(mainArticleRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
mainArticle = gson.fromJson(body.string(), new TypeToken<Article>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
//Configuration request
client.newCall(configurationRequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
config = gson.fromJson(body.string(), new TypeToken<Configuration>() {
}.getType());
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
try {
latch.await();
} catch (InterruptedException e) {
error.set(true);
}
notifyObservers(error.get() ? HTTPRequestStatus.HTTPERROR : HTTPRequestStatus.OK);
} catch (KeyManagementException | NoSuchAlgorithmException | KeyStoreException e) {
notifyObservers(HTTPRequestStatus.TLSERROR);
}
}
});
exService.shutdown();
}
}
This code calls several HTTP requests asynchronously and wait for all of them to conclude. If any request fails it notifies with an error, otherwise success. These requests returns JSON and I parse them using Gson.
For simplicity I have only showed two requests, however I want to refactor this code for any number of requests. There is a lot of similar code, but I can't figure a way to refactor it. I have already tried to create a custom Callback class however I can't figure a way to pass a Type and return the parsed value.
How would you approach this one?
java android gson
java android gson
asked Dec 27 '18 at 17:51
Exprove
1063
New contributor
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asked Dec 27 '18 at 17:51
Exprove
1063
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edited Dec 28 '18 at 0:08
asked Dec 27 '18 at 17:51
Exprove
1063
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asked Dec 27 '18 at 17:51
Exprove
1063
asked Dec 27 '18 at 17:51
Exprove
1063
1063
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Exprove is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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2
Simplicity isn't usually the way to go here. I recommend you show the rest of your code. You might get different answers based on the less "simple" code than you would with what you currently have. Also please change the title to describe What your code Does as apposed to your goal. (Almost everyone wants to refactor their code.)
– bruglesco
Dec 27 '18 at 19:36
@bruglesco The difference between this code and the actual one is that there are like 10RequestObjects and 10client.newCalls(request), should I include them anyway?
– Exprove
Dec 27 '18 at 20:55
Yes. You should.
– bruglesco
Dec 27 '18 at 21:17
add a comment |
2
Simplicity isn't usually the way to go here. I recommend you show the rest of your code. You might get different answers based on the less "simple" code than you would with what you currently have. Also please change the title to describe What your code Does as apposed to your goal. (Almost everyone wants to refactor their code.)
– bruglesco
Dec 27 '18 at 19:36
@bruglesco The difference between this code and the actual one is that there are like 10RequestObjects and 10client.newCalls(request), should I include them anyway?
– Exprove
Dec 27 '18 at 20:55
Yes. You should.
– bruglesco
Dec 27 '18 at 21:17
2
2
Simplicity isn't usually the way to go here. I recommend you show the rest of your code. You might get different answers based on the less "simple" code than you would with what you currently have. Also please change the title to describe What your code Does as apposed to your goal. (Almost everyone wants to refactor their code.)
– bruglesco
Dec 27 '18 at 19:36
Simplicity isn't usually the way to go here. I recommend you show the rest of your code. You might get different answers based on the less "simple" code than you would with what you currently have. Also please change the title to describe What your code Does as apposed to your goal. (Almost everyone wants to refactor their code.)
– bruglesco
Dec 27 '18 at 19:36
@bruglesco The difference between this code and the actual one is that there are like 10
Request Objects and 10 client.newCalls(request) , should I include them anyway?– Exprove
Dec 27 '18 at 20:55
@bruglesco The difference between this code and the actual one is that there are like 10
Request Objects and 10 client.newCalls(request) , should I include them anyway?– Exprove
Dec 27 '18 at 20:55
Yes. You should.
– bruglesco
Dec 27 '18 at 21:17
Yes. You should.
– bruglesco
Dec 27 '18 at 21:17
add a comment |
2 Answers
2
active
oldest
votes
2
Welcome to Code Review!
Thanks for sharing your code.
As you observed the main problem is code duplication.
We have basically two options to solve that problem. Both of them use the basic approach to separate the common code from the different code and "inject" the differing code into the common code.
prepare injecting differing code
When looking at your code the only difference between the //Article Request and the //Events Request are these lines:
//Article Request
articles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
//Events Request
events = gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType());
One problem here is that you change the objects pointed to by the member variables articles and events. We could make is easier to change if the objects would be reused:
//Article Request
articles.clear();
articles.addAll(gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType()));
//Events Request
events.clear();
events.addAll(gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType()));
now we can extract one of that parts to a new Method using the IDEs automated refactoring "extract method":
private void deserializeJson(
List<Event> events,
Gson gson,
ResponseBody body
){
events.clear();
events.addAll(gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType()));
}
//Events Request
// ...
} else {
deserializeJson((List<Event>)events,
Gson gson,
ResponseBody body);
}
Next we have to mat this new private method "generic":
private <L extends List> void deserializeJson(
L events,
Gson gson,
ResponseBody body
){
events.clear();
events.addAll(gson.fromJson(body.string(), new TypeToken<L>() {
}.getType()));
}
Now we can change toe other place too:
//Articles Request
// ...
} else {
deserializeJson((List<Article>)articles);
}
from here we have two options:
- consolidating the common code in a single generic typed method.
- puttig the difering code into an "specialized classes" providing the differing behavior via an common interface.
common code in a single generic typed method
We basically do he same as above: we extract the //Events Request section or the //Articles Request into a new private method and make it "generic"
private <L extends List> void deserializeFromJson(
L theList,
OkHttpClient client,
Gson gson
){
client.newCall(articlesrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
deserializeJson((L)theList, gson, body);
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
}
//Article Request
deserializeFromJson(
(List<Articles>)articles,
client,
gson
);
//Events Request
client.newCall(eventsrequest).enqueue(new Callback() {
// ...
and then also replace the other part:
//Article Request
deserializeFromJson(
(List<Articles>)articles,
client,
gson
);
//Events Request
deserializeFromJson(
(List<Event>)events,
client,
gson
);
creating specialized classes with interface
for this we have to move the private method created in the first section into a new inner class
class your current class:
private static class JsonDeserializer<T> {
void deserialize(
List<T> theList,
Gson gson,
ResponseBody body
){
theList.clear();
theList.addAll(gson.fromJson(body.string(), new TypeToken<List<T>>() {
}.getType()));
}
}
// ...
//Articles Request
// ...
} else {
new JsonDeserializer<Article>().deserialize(articles, gson, body);
}
//...
Since articles and events are member variables I'd rather have them as constructor parameters in the new class:
class your current class:
private static class JsonDeserializer<T> {
private final List<T> theList;
JsonDeserializer( List<T> theList){
this.theList = theList;
}
void deserialize(
Gson gson,
ResponseBody body
){
theList.clear();
theList.addAll(gson.fromJson(body.string(), new TypeToken<List<T>>() {
}.getType()));
}
}
// ...
//Articles Request
// ...
} else {
new JsonDeserializer<Article>(articles).deserialize(gson, body);
}
//...
//Event Request
// ...
} else {
new JsonDeserializer<Event>(eventss).deserialize(gson, body);
}
//...
Now we can create the JsonDeserializer instances at the top of the method:
private void loadRepository() {
JsonDeserializer<Article> articleDeserializer = new JsonDeserializer<>(articles);
JsonDeserializer<Event> eventDeserializer = new JsonDeserializer<>(event);
ExecutorService exService = Executors.newSingleThreadExecutor();
// ...
//Articles Request
// ...
} else {
articleDeserializer.deserialize(gson, body);
}
//...
//Event Request
// ...
} else {
eventDeserializer.deserialize(gson, body);
}
//...
Now the only difference left in //Articles Request section and //Event Request section is the name of the variable. So we can put the two JsonDeserializer instances into a collection and apply the *common code * as a loop:
private void loadRepository() {
JsonDeserializer<?> deserializers = Arrays.asList(
new JsonDeserializer<Article>(articles),
new JsonDeserializer<Event>(event)
);
ExecutorService exService = Executors.newSingleThreadExecutor();
// ...
Request eventsrequest = requestbuilder.url("https://apiurlevents").build();
//Article Request changed to loop
for(JsonDeserializer<?> deserializer: deserializers){
client.newCall(articlesrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
deserializer.deserialize(gson, body);
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
}
try {
latch.await();
} catch (InterruptedException e) {
error.set(true);
}
New document types are just new instances in the collection.
answered Dec 27 '18 at 22:02
Timothy Truckle
4,838416
Really appreciate your help. That refactor would work, however not all my class member variables are from typeList. Added more requests examples. If I replaceList<T>to<T>would that work? Ofc I would declare JsonDeserializer as<List<Article>>for example.
– Exprove
Dec 28 '18 at 0:12
@Exprove however not all my class member variables are from type List I'd create anotherJsonDeserializerthat deserializes the generic type directly. Problem might be to get the de-serialized object out of theJsonDeserializerinstance. replacing theListparameter of the constructor with a Listener might work.
– Timothy Truckle
Dec 28 '18 at 0:20
add a comment |
1
You could use a CompletableFuture for this. Make each call return a completed future with the body, or an exceptionally completed future with an error:
private CompletableFuture<String> call(String url) {
CompletableFuture<String> future = new CompletableFuture<>();
OkHttpClient client = new OkHttpClient.Builder().connectTimeout(15, TimeUnit.SECONDS).build();
client.newCall(requestbuilder.url(url).build()).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
future.completeExceptionally(e);
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
throw new IOException("Http error");
} else {
future.complete(body.string());
}
} catch (IOException | JsonSyntaxException e) {
future.completeExceptionally(e);
}
}
});
return future;
}
Then add a generic method to make the calls and deserialize the results:
private <T> Future<T> callAndDeserialize(String url, Gson gson, TypeToken<T> typeToken) {
CompletableFuture<String> future = call(url);
return future.thenApply(new Function<String, T>() {
public T apply(String body) {
return gson.fromJson(body, typeToken.getType()));
}
});
}
The loadRepository code would then be something like:
final Gson gson = new GsonBuilder().registerTypeHierarchyAdapter(Calendar.class, new CalendarGson()).create();
Future<List<Article>> articlesFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<List<Event>> eventsFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Event>>() {});
Future<List<Article>> sportsFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<List<Article>> fitnessFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<List<Article>> governmentFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<Article> mainArticleFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<Article>() {});
Future<Configuration> configurationFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<Configuration>() {});
try {
articles = articlesFuture.get();
events = eventsFuture.get();
sportArticles = sportsFuture.get();
fitnessArticles = fitnessFuture.get();
governmentArticles = governmentFuture.get();
mainArticle = mainArticleFuture.get();
config = configurationFuture.get();
notifyObservers(HTTPRequestStatus.OK);
} catch (ExecutionException e) {
if(e.getCause() instanceof KeyManagementException || e.getCause() instanceof NoSuchAlgorithmException || e.getCause() instanceof KeyStoreException) {
notifyObservers(HTTPRequestStatus.TLSERROR);
} else {
notifyObservers(HTTPRequestStatus.HTTPERROR);
}
}
The ExecutionException at the end now retains the exception messages, causes and stacktraces. In case there's any unexpected errors you need to debug, you can also log this exception as well notifying the observers.
answered 20 hours ago
fgb
48538
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
2
Welcome to Code Review!
Thanks for sharing your code.
As you observed the main problem is code duplication.
We have basically two options to solve that problem. Both of them use the basic approach to separate the common code from the different code and "inject" the differing code into the common code.
prepare injecting differing code
When looking at your code the only difference between the //Article Request and the //Events Request are these lines:
//Article Request
articles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
//Events Request
events = gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType());
One problem here is that you change the objects pointed to by the member variables articles and events. We could make is easier to change if the objects would be reused:
//Article Request
articles.clear();
articles.addAll(gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType()));
//Events Request
events.clear();
events.addAll(gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType()));
now we can extract one of that parts to a new Method using the IDEs automated refactoring "extract method":
private void deserializeJson(
List<Event> events,
Gson gson,
ResponseBody body
){
events.clear();
events.addAll(gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType()));
}
//Events Request
// ...
} else {
deserializeJson((List<Event>)events,
Gson gson,
ResponseBody body);
}
Next we have to mat this new private method "generic":
private <L extends List> void deserializeJson(
L events,
Gson gson,
ResponseBody body
){
events.clear();
events.addAll(gson.fromJson(body.string(), new TypeToken<L>() {
}.getType()));
}
Now we can change toe other place too:
//Articles Request
// ...
} else {
deserializeJson((List<Article>)articles);
}
from here we have two options:
- consolidating the common code in a single generic typed method.
- puttig the difering code into an "specialized classes" providing the differing behavior via an common interface.
common code in a single generic typed method
We basically do he same as above: we extract the //Events Request section or the //Articles Request into a new private method and make it "generic"
private <L extends List> void deserializeFromJson(
L theList,
OkHttpClient client,
Gson gson
){
client.newCall(articlesrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
deserializeJson((L)theList, gson, body);
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
}
//Article Request
deserializeFromJson(
(List<Articles>)articles,
client,
gson
);
//Events Request
client.newCall(eventsrequest).enqueue(new Callback() {
// ...
and then also replace the other part:
//Article Request
deserializeFromJson(
(List<Articles>)articles,
client,
gson
);
//Events Request
deserializeFromJson(
(List<Event>)events,
client,
gson
);
creating specialized classes with interface
for this we have to move the private method created in the first section into a new inner class
class your current class:
private static class JsonDeserializer<T> {
void deserialize(
List<T> theList,
Gson gson,
ResponseBody body
){
theList.clear();
theList.addAll(gson.fromJson(body.string(), new TypeToken<List<T>>() {
}.getType()));
}
}
// ...
//Articles Request
// ...
} else {
new JsonDeserializer<Article>().deserialize(articles, gson, body);
}
//...
Since articles and events are member variables I'd rather have them as constructor parameters in the new class:
class your current class:
private static class JsonDeserializer<T> {
private final List<T> theList;
JsonDeserializer( List<T> theList){
this.theList = theList;
}
void deserialize(
Gson gson,
ResponseBody body
){
theList.clear();
theList.addAll(gson.fromJson(body.string(), new TypeToken<List<T>>() {
}.getType()));
}
}
// ...
//Articles Request
// ...
} else {
new JsonDeserializer<Article>(articles).deserialize(gson, body);
}
//...
//Event Request
// ...
} else {
new JsonDeserializer<Event>(eventss).deserialize(gson, body);
}
//...
Now we can create the JsonDeserializer instances at the top of the method:
private void loadRepository() {
JsonDeserializer<Article> articleDeserializer = new JsonDeserializer<>(articles);
JsonDeserializer<Event> eventDeserializer = new JsonDeserializer<>(event);
ExecutorService exService = Executors.newSingleThreadExecutor();
// ...
//Articles Request
// ...
} else {
articleDeserializer.deserialize(gson, body);
}
//...
//Event Request
// ...
} else {
eventDeserializer.deserialize(gson, body);
}
//...
Now the only difference left in //Articles Request section and //Event Request section is the name of the variable. So we can put the two JsonDeserializer instances into a collection and apply the *common code * as a loop:
private void loadRepository() {
JsonDeserializer<?> deserializers = Arrays.asList(
new JsonDeserializer<Article>(articles),
new JsonDeserializer<Event>(event)
);
ExecutorService exService = Executors.newSingleThreadExecutor();
// ...
Request eventsrequest = requestbuilder.url("https://apiurlevents").build();
//Article Request changed to loop
for(JsonDeserializer<?> deserializer: deserializers){
client.newCall(articlesrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
deserializer.deserialize(gson, body);
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
}
try {
latch.await();
} catch (InterruptedException e) {
error.set(true);
}
New document types are just new instances in the collection.
answered Dec 27 '18 at 22:02
Timothy Truckle
4,838416
Really appreciate your help. That refactor would work, however not all my class member variables are from typeList. Added more requests examples. If I replaceList<T>to<T>would that work? Ofc I would declare JsonDeserializer as<List<Article>>for example.
– Exprove
Dec 28 '18 at 0:12
@Exprove however not all my class member variables are from type List I'd create anotherJsonDeserializerthat deserializes the generic type directly. Problem might be to get the de-serialized object out of theJsonDeserializerinstance. replacing theListparameter of the constructor with a Listener might work.
– Timothy Truckle
Dec 28 '18 at 0:20
add a comment |
2
Welcome to Code Review!
Thanks for sharing your code.
As you observed the main problem is code duplication.
We have basically two options to solve that problem. Both of them use the basic approach to separate the common code from the different code and "inject" the differing code into the common code.
prepare injecting differing code
When looking at your code the only difference between the //Article Request and the //Events Request are these lines:
//Article Request
articles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
//Events Request
events = gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType());
One problem here is that you change the objects pointed to by the member variables articles and events. We could make is easier to change if the objects would be reused:
//Article Request
articles.clear();
articles.addAll(gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType()));
//Events Request
events.clear();
events.addAll(gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType()));
now we can extract one of that parts to a new Method using the IDEs automated refactoring "extract method":
private void deserializeJson(
List<Event> events,
Gson gson,
ResponseBody body
){
events.clear();
events.addAll(gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType()));
}
//Events Request
// ...
} else {
deserializeJson((List<Event>)events,
Gson gson,
ResponseBody body);
}
Next we have to mat this new private method "generic":
private <L extends List> void deserializeJson(
L events,
Gson gson,
ResponseBody body
){
events.clear();
events.addAll(gson.fromJson(body.string(), new TypeToken<L>() {
}.getType()));
}
Now we can change toe other place too:
//Articles Request
// ...
} else {
deserializeJson((List<Article>)articles);
}
from here we have two options:
- consolidating the common code in a single generic typed method.
- puttig the difering code into an "specialized classes" providing the differing behavior via an common interface.
common code in a single generic typed method
We basically do he same as above: we extract the //Events Request section or the //Articles Request into a new private method and make it "generic"
private <L extends List> void deserializeFromJson(
L theList,
OkHttpClient client,
Gson gson
){
client.newCall(articlesrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
deserializeJson((L)theList, gson, body);
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
}
//Article Request
deserializeFromJson(
(List<Articles>)articles,
client,
gson
);
//Events Request
client.newCall(eventsrequest).enqueue(new Callback() {
// ...
and then also replace the other part:
//Article Request
deserializeFromJson(
(List<Articles>)articles,
client,
gson
);
//Events Request
deserializeFromJson(
(List<Event>)events,
client,
gson
);
creating specialized classes with interface
for this we have to move the private method created in the first section into a new inner class
class your current class:
private static class JsonDeserializer<T> {
void deserialize(
List<T> theList,
Gson gson,
ResponseBody body
){
theList.clear();
theList.addAll(gson.fromJson(body.string(), new TypeToken<List<T>>() {
}.getType()));
}
}
// ...
//Articles Request
// ...
} else {
new JsonDeserializer<Article>().deserialize(articles, gson, body);
}
//...
Since articles and events are member variables I'd rather have them as constructor parameters in the new class:
class your current class:
private static class JsonDeserializer<T> {
private final List<T> theList;
JsonDeserializer( List<T> theList){
this.theList = theList;
}
void deserialize(
Gson gson,
ResponseBody body
){
theList.clear();
theList.addAll(gson.fromJson(body.string(), new TypeToken<List<T>>() {
}.getType()));
}
}
// ...
//Articles Request
// ...
} else {
new JsonDeserializer<Article>(articles).deserialize(gson, body);
}
//...
//Event Request
// ...
} else {
new JsonDeserializer<Event>(eventss).deserialize(gson, body);
}
//...
Now we can create the JsonDeserializer instances at the top of the method:
private void loadRepository() {
JsonDeserializer<Article> articleDeserializer = new JsonDeserializer<>(articles);
JsonDeserializer<Event> eventDeserializer = new JsonDeserializer<>(event);
ExecutorService exService = Executors.newSingleThreadExecutor();
// ...
//Articles Request
// ...
} else {
articleDeserializer.deserialize(gson, body);
}
//...
//Event Request
// ...
} else {
eventDeserializer.deserialize(gson, body);
}
//...
Now the only difference left in //Articles Request section and //Event Request section is the name of the variable. So we can put the two JsonDeserializer instances into a collection and apply the *common code * as a loop:
private void loadRepository() {
JsonDeserializer<?> deserializers = Arrays.asList(
new JsonDeserializer<Article>(articles),
new JsonDeserializer<Event>(event)
);
ExecutorService exService = Executors.newSingleThreadExecutor();
// ...
Request eventsrequest = requestbuilder.url("https://apiurlevents").build();
//Article Request changed to loop
for(JsonDeserializer<?> deserializer: deserializers){
client.newCall(articlesrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
deserializer.deserialize(gson, body);
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
}
try {
latch.await();
} catch (InterruptedException e) {
error.set(true);
}
New document types are just new instances in the collection.
answered Dec 27 '18 at 22:02
Timothy Truckle
4,838416
Really appreciate your help. That refactor would work, however not all my class member variables are from typeList. Added more requests examples. If I replaceList<T>to<T>would that work? Ofc I would declare JsonDeserializer as<List<Article>>for example.
– Exprove
Dec 28 '18 at 0:12
@Exprove however not all my class member variables are from type List I'd create anotherJsonDeserializerthat deserializes the generic type directly. Problem might be to get the de-serialized object out of theJsonDeserializerinstance. replacing theListparameter of the constructor with a Listener might work.
– Timothy Truckle
Dec 28 '18 at 0:20
add a comment |
2
2
2
Welcome to Code Review!
Thanks for sharing your code.
As you observed the main problem is code duplication.
We have basically two options to solve that problem. Both of them use the basic approach to separate the common code from the different code and "inject" the differing code into the common code.
prepare injecting differing code
When looking at your code the only difference between the //Article Request and the //Events Request are these lines:
//Article Request
articles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
//Events Request
events = gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType());
One problem here is that you change the objects pointed to by the member variables articles and events. We could make is easier to change if the objects would be reused:
//Article Request
articles.clear();
articles.addAll(gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType()));
//Events Request
events.clear();
events.addAll(gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType()));
now we can extract one of that parts to a new Method using the IDEs automated refactoring "extract method":
private void deserializeJson(
List<Event> events,
Gson gson,
ResponseBody body
){
events.clear();
events.addAll(gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType()));
}
//Events Request
// ...
} else {
deserializeJson((List<Event>)events,
Gson gson,
ResponseBody body);
}
Next we have to mat this new private method "generic":
private <L extends List> void deserializeJson(
L events,
Gson gson,
ResponseBody body
){
events.clear();
events.addAll(gson.fromJson(body.string(), new TypeToken<L>() {
}.getType()));
}
Now we can change toe other place too:
//Articles Request
// ...
} else {
deserializeJson((List<Article>)articles);
}
from here we have two options:
- consolidating the common code in a single generic typed method.
- puttig the difering code into an "specialized classes" providing the differing behavior via an common interface.
common code in a single generic typed method
We basically do he same as above: we extract the //Events Request section or the //Articles Request into a new private method and make it "generic"
private <L extends List> void deserializeFromJson(
L theList,
OkHttpClient client,
Gson gson
){
client.newCall(articlesrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
deserializeJson((L)theList, gson, body);
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
}
//Article Request
deserializeFromJson(
(List<Articles>)articles,
client,
gson
);
//Events Request
client.newCall(eventsrequest).enqueue(new Callback() {
// ...
and then also replace the other part:
//Article Request
deserializeFromJson(
(List<Articles>)articles,
client,
gson
);
//Events Request
deserializeFromJson(
(List<Event>)events,
client,
gson
);
creating specialized classes with interface
for this we have to move the private method created in the first section into a new inner class
class your current class:
private static class JsonDeserializer<T> {
void deserialize(
List<T> theList,
Gson gson,
ResponseBody body
){
theList.clear();
theList.addAll(gson.fromJson(body.string(), new TypeToken<List<T>>() {
}.getType()));
}
}
// ...
//Articles Request
// ...
} else {
new JsonDeserializer<Article>().deserialize(articles, gson, body);
}
//...
Since articles and events are member variables I'd rather have them as constructor parameters in the new class:
class your current class:
private static class JsonDeserializer<T> {
private final List<T> theList;
JsonDeserializer( List<T> theList){
this.theList = theList;
}
void deserialize(
Gson gson,
ResponseBody body
){
theList.clear();
theList.addAll(gson.fromJson(body.string(), new TypeToken<List<T>>() {
}.getType()));
}
}
// ...
//Articles Request
// ...
} else {
new JsonDeserializer<Article>(articles).deserialize(gson, body);
}
//...
//Event Request
// ...
} else {
new JsonDeserializer<Event>(eventss).deserialize(gson, body);
}
//...
Now we can create the JsonDeserializer instances at the top of the method:
private void loadRepository() {
JsonDeserializer<Article> articleDeserializer = new JsonDeserializer<>(articles);
JsonDeserializer<Event> eventDeserializer = new JsonDeserializer<>(event);
ExecutorService exService = Executors.newSingleThreadExecutor();
// ...
//Articles Request
// ...
} else {
articleDeserializer.deserialize(gson, body);
}
//...
//Event Request
// ...
} else {
eventDeserializer.deserialize(gson, body);
}
//...
Now the only difference left in //Articles Request section and //Event Request section is the name of the variable. So we can put the two JsonDeserializer instances into a collection and apply the *common code * as a loop:
private void loadRepository() {
JsonDeserializer<?> deserializers = Arrays.asList(
new JsonDeserializer<Article>(articles),
new JsonDeserializer<Event>(event)
);
ExecutorService exService = Executors.newSingleThreadExecutor();
// ...
Request eventsrequest = requestbuilder.url("https://apiurlevents").build();
//Article Request changed to loop
for(JsonDeserializer<?> deserializer: deserializers){
client.newCall(articlesrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
deserializer.deserialize(gson, body);
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
}
try {
latch.await();
} catch (InterruptedException e) {
error.set(true);
}
New document types are just new instances in the collection.
answered Dec 27 '18 at 22:02
Timothy Truckle
4,838416
Welcome to Code Review!
Thanks for sharing your code.
As you observed the main problem is code duplication.
We have basically two options to solve that problem. Both of them use the basic approach to separate the common code from the different code and "inject" the differing code into the common code.
prepare injecting differing code
When looking at your code the only difference between the //Article Request and the //Events Request are these lines:
//Article Request
articles = gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType());
//Events Request
events = gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType());
One problem here is that you change the objects pointed to by the member variables articles and events. We could make is easier to change if the objects would be reused:
//Article Request
articles.clear();
articles.addAll(gson.fromJson(body.string(), new TypeToken<List<Article>>() {
}.getType()));
//Events Request
events.clear();
events.addAll(gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType()));
now we can extract one of that parts to a new Method using the IDEs automated refactoring "extract method":
private void deserializeJson(
List<Event> events,
Gson gson,
ResponseBody body
){
events.clear();
events.addAll(gson.fromJson(body.string(), new TypeToken<List<Event>>() {
}.getType()));
}
//Events Request
// ...
} else {
deserializeJson((List<Event>)events,
Gson gson,
ResponseBody body);
}
Next we have to mat this new private method "generic":
private <L extends List> void deserializeJson(
L events,
Gson gson,
ResponseBody body
){
events.clear();
events.addAll(gson.fromJson(body.string(), new TypeToken<L>() {
}.getType()));
}
Now we can change toe other place too:
//Articles Request
// ...
} else {
deserializeJson((List<Article>)articles);
}
from here we have two options:
- consolidating the common code in a single generic typed method.
- puttig the difering code into an "specialized classes" providing the differing behavior via an common interface.
common code in a single generic typed method
We basically do he same as above: we extract the //Events Request section or the //Articles Request into a new private method and make it "generic"
private <L extends List> void deserializeFromJson(
L theList,
OkHttpClient client,
Gson gson
){
client.newCall(articlesrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
deserializeJson((L)theList, gson, body);
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
}
//Article Request
deserializeFromJson(
(List<Articles>)articles,
client,
gson
);
//Events Request
client.newCall(eventsrequest).enqueue(new Callback() {
// ...
and then also replace the other part:
//Article Request
deserializeFromJson(
(List<Articles>)articles,
client,
gson
);
//Events Request
deserializeFromJson(
(List<Event>)events,
client,
gson
);
creating specialized classes with interface
for this we have to move the private method created in the first section into a new inner class
class your current class:
private static class JsonDeserializer<T> {
void deserialize(
List<T> theList,
Gson gson,
ResponseBody body
){
theList.clear();
theList.addAll(gson.fromJson(body.string(), new TypeToken<List<T>>() {
}.getType()));
}
}
// ...
//Articles Request
// ...
} else {
new JsonDeserializer<Article>().deserialize(articles, gson, body);
}
//...
Since articles and events are member variables I'd rather have them as constructor parameters in the new class:
class your current class:
private static class JsonDeserializer<T> {
private final List<T> theList;
JsonDeserializer( List<T> theList){
this.theList = theList;
}
void deserialize(
Gson gson,
ResponseBody body
){
theList.clear();
theList.addAll(gson.fromJson(body.string(), new TypeToken<List<T>>() {
}.getType()));
}
}
// ...
//Articles Request
// ...
} else {
new JsonDeserializer<Article>(articles).deserialize(gson, body);
}
//...
//Event Request
// ...
} else {
new JsonDeserializer<Event>(eventss).deserialize(gson, body);
}
//...
Now we can create the JsonDeserializer instances at the top of the method:
private void loadRepository() {
JsonDeserializer<Article> articleDeserializer = new JsonDeserializer<>(articles);
JsonDeserializer<Event> eventDeserializer = new JsonDeserializer<>(event);
ExecutorService exService = Executors.newSingleThreadExecutor();
// ...
//Articles Request
// ...
} else {
articleDeserializer.deserialize(gson, body);
}
//...
//Event Request
// ...
} else {
eventDeserializer.deserialize(gson, body);
}
//...
Now the only difference left in //Articles Request section and //Event Request section is the name of the variable. So we can put the two JsonDeserializer instances into a collection and apply the *common code * as a loop:
private void loadRepository() {
JsonDeserializer<?> deserializers = Arrays.asList(
new JsonDeserializer<Article>(articles),
new JsonDeserializer<Event>(event)
);
ExecutorService exService = Executors.newSingleThreadExecutor();
// ...
Request eventsrequest = requestbuilder.url("https://apiurlevents").build();
//Article Request changed to loop
for(JsonDeserializer<?> deserializer: deserializers){
client.newCall(articlesrequest).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
error.set(true);
latch.countDown();
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
error.set(true);
} else {
deserializer.deserialize(gson, body);
}
} catch (IOException | JsonSyntaxException e) {
error.set(true);
}
latch.countDown();
}
});
}
try {
latch.await();
} catch (InterruptedException e) {
error.set(true);
}
New document types are just new instances in the collection.
answered Dec 27 '18 at 22:02
Timothy Truckle
4,838416
answered Dec 27 '18 at 22:02
Timothy Truckle
4,838416
answered Dec 27 '18 at 22:02
Timothy Truckle
4,838416
answered Dec 27 '18 at 22:02
Timothy Truckle
4,838416
4,838416
Really appreciate your help. That refactor would work, however not all my class member variables are from typeList. Added more requests examples. If I replaceList<T>to<T>would that work? Ofc I would declare JsonDeserializer as<List<Article>>for example.
– Exprove
Dec 28 '18 at 0:12
@Exprove however not all my class member variables are from type List I'd create anotherJsonDeserializerthat deserializes the generic type directly. Problem might be to get the de-serialized object out of theJsonDeserializerinstance. replacing theListparameter of the constructor with a Listener might work.
– Timothy Truckle
Dec 28 '18 at 0:20
add a comment |
Really appreciate your help. That refactor would work, however not all my class member variables are from typeList. Added more requests examples. If I replaceList<T>to<T>would that work? Ofc I would declare JsonDeserializer as<List<Article>>for example.
– Exprove
Dec 28 '18 at 0:12
@Exprove however not all my class member variables are from type List I'd create anotherJsonDeserializerthat deserializes the generic type directly. Problem might be to get the de-serialized object out of theJsonDeserializerinstance. replacing theListparameter of the constructor with a Listener might work.
– Timothy Truckle
Dec 28 '18 at 0:20
Really appreciate your help. That refactor would work, however not all my class member variables are from type
List. Added more requests examples. If I replace List<T> to <T> would that work? Ofc I would declare JsonDeserializer as <List<Article>> for example.– Exprove
Dec 28 '18 at 0:12
Really appreciate your help. That refactor would work, however not all my class member variables are from type
List. Added more requests examples. If I replace List<T> to <T> would that work? Ofc I would declare JsonDeserializer as <List<Article>> for example.– Exprove
Dec 28 '18 at 0:12
@Exprove however not all my class member variables are from type List I'd create another
JsonDeserializer that deserializes the generic type directly. Problem might be to get the de-serialized object out of the JsonDeserializer instance. replacing the List parameter of the constructor with a Listener might work.– Timothy Truckle
Dec 28 '18 at 0:20
@Exprove however not all my class member variables are from type List I'd create another
JsonDeserializer that deserializes the generic type directly. Problem might be to get the de-serialized object out of the JsonDeserializer instance. replacing the List parameter of the constructor with a Listener might work.– Timothy Truckle
Dec 28 '18 at 0:20
add a comment |
1
You could use a CompletableFuture for this. Make each call return a completed future with the body, or an exceptionally completed future with an error:
private CompletableFuture<String> call(String url) {
CompletableFuture<String> future = new CompletableFuture<>();
OkHttpClient client = new OkHttpClient.Builder().connectTimeout(15, TimeUnit.SECONDS).build();
client.newCall(requestbuilder.url(url).build()).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
future.completeExceptionally(e);
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
throw new IOException("Http error");
} else {
future.complete(body.string());
}
} catch (IOException | JsonSyntaxException e) {
future.completeExceptionally(e);
}
}
});
return future;
}
Then add a generic method to make the calls and deserialize the results:
private <T> Future<T> callAndDeserialize(String url, Gson gson, TypeToken<T> typeToken) {
CompletableFuture<String> future = call(url);
return future.thenApply(new Function<String, T>() {
public T apply(String body) {
return gson.fromJson(body, typeToken.getType()));
}
});
}
The loadRepository code would then be something like:
final Gson gson = new GsonBuilder().registerTypeHierarchyAdapter(Calendar.class, new CalendarGson()).create();
Future<List<Article>> articlesFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<List<Event>> eventsFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Event>>() {});
Future<List<Article>> sportsFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<List<Article>> fitnessFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<List<Article>> governmentFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<Article> mainArticleFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<Article>() {});
Future<Configuration> configurationFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<Configuration>() {});
try {
articles = articlesFuture.get();
events = eventsFuture.get();
sportArticles = sportsFuture.get();
fitnessArticles = fitnessFuture.get();
governmentArticles = governmentFuture.get();
mainArticle = mainArticleFuture.get();
config = configurationFuture.get();
notifyObservers(HTTPRequestStatus.OK);
} catch (ExecutionException e) {
if(e.getCause() instanceof KeyManagementException || e.getCause() instanceof NoSuchAlgorithmException || e.getCause() instanceof KeyStoreException) {
notifyObservers(HTTPRequestStatus.TLSERROR);
} else {
notifyObservers(HTTPRequestStatus.HTTPERROR);
}
}
The ExecutionException at the end now retains the exception messages, causes and stacktraces. In case there's any unexpected errors you need to debug, you can also log this exception as well notifying the observers.
answered 20 hours ago
fgb
48538
add a comment |
1
You could use a CompletableFuture for this. Make each call return a completed future with the body, or an exceptionally completed future with an error:
private CompletableFuture<String> call(String url) {
CompletableFuture<String> future = new CompletableFuture<>();
OkHttpClient client = new OkHttpClient.Builder().connectTimeout(15, TimeUnit.SECONDS).build();
client.newCall(requestbuilder.url(url).build()).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
future.completeExceptionally(e);
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
throw new IOException("Http error");
} else {
future.complete(body.string());
}
} catch (IOException | JsonSyntaxException e) {
future.completeExceptionally(e);
}
}
});
return future;
}
Then add a generic method to make the calls and deserialize the results:
private <T> Future<T> callAndDeserialize(String url, Gson gson, TypeToken<T> typeToken) {
CompletableFuture<String> future = call(url);
return future.thenApply(new Function<String, T>() {
public T apply(String body) {
return gson.fromJson(body, typeToken.getType()));
}
});
}
The loadRepository code would then be something like:
final Gson gson = new GsonBuilder().registerTypeHierarchyAdapter(Calendar.class, new CalendarGson()).create();
Future<List<Article>> articlesFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<List<Event>> eventsFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Event>>() {});
Future<List<Article>> sportsFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<List<Article>> fitnessFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<List<Article>> governmentFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<Article> mainArticleFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<Article>() {});
Future<Configuration> configurationFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<Configuration>() {});
try {
articles = articlesFuture.get();
events = eventsFuture.get();
sportArticles = sportsFuture.get();
fitnessArticles = fitnessFuture.get();
governmentArticles = governmentFuture.get();
mainArticle = mainArticleFuture.get();
config = configurationFuture.get();
notifyObservers(HTTPRequestStatus.OK);
} catch (ExecutionException e) {
if(e.getCause() instanceof KeyManagementException || e.getCause() instanceof NoSuchAlgorithmException || e.getCause() instanceof KeyStoreException) {
notifyObservers(HTTPRequestStatus.TLSERROR);
} else {
notifyObservers(HTTPRequestStatus.HTTPERROR);
}
}
The ExecutionException at the end now retains the exception messages, causes and stacktraces. In case there's any unexpected errors you need to debug, you can also log this exception as well notifying the observers.
answered 20 hours ago
fgb
48538
add a comment |
1
1
1
You could use a CompletableFuture for this. Make each call return a completed future with the body, or an exceptionally completed future with an error:
private CompletableFuture<String> call(String url) {
CompletableFuture<String> future = new CompletableFuture<>();
OkHttpClient client = new OkHttpClient.Builder().connectTimeout(15, TimeUnit.SECONDS).build();
client.newCall(requestbuilder.url(url).build()).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
future.completeExceptionally(e);
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
throw new IOException("Http error");
} else {
future.complete(body.string());
}
} catch (IOException | JsonSyntaxException e) {
future.completeExceptionally(e);
}
}
});
return future;
}
Then add a generic method to make the calls and deserialize the results:
private <T> Future<T> callAndDeserialize(String url, Gson gson, TypeToken<T> typeToken) {
CompletableFuture<String> future = call(url);
return future.thenApply(new Function<String, T>() {
public T apply(String body) {
return gson.fromJson(body, typeToken.getType()));
}
});
}
The loadRepository code would then be something like:
final Gson gson = new GsonBuilder().registerTypeHierarchyAdapter(Calendar.class, new CalendarGson()).create();
Future<List<Article>> articlesFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<List<Event>> eventsFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Event>>() {});
Future<List<Article>> sportsFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<List<Article>> fitnessFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<List<Article>> governmentFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<Article> mainArticleFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<Article>() {});
Future<Configuration> configurationFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<Configuration>() {});
try {
articles = articlesFuture.get();
events = eventsFuture.get();
sportArticles = sportsFuture.get();
fitnessArticles = fitnessFuture.get();
governmentArticles = governmentFuture.get();
mainArticle = mainArticleFuture.get();
config = configurationFuture.get();
notifyObservers(HTTPRequestStatus.OK);
} catch (ExecutionException e) {
if(e.getCause() instanceof KeyManagementException || e.getCause() instanceof NoSuchAlgorithmException || e.getCause() instanceof KeyStoreException) {
notifyObservers(HTTPRequestStatus.TLSERROR);
} else {
notifyObservers(HTTPRequestStatus.HTTPERROR);
}
}
The ExecutionException at the end now retains the exception messages, causes and stacktraces. In case there's any unexpected errors you need to debug, you can also log this exception as well notifying the observers.
answered 20 hours ago
fgb
48538
You could use a CompletableFuture for this. Make each call return a completed future with the body, or an exceptionally completed future with an error:
private CompletableFuture<String> call(String url) {
CompletableFuture<String> future = new CompletableFuture<>();
OkHttpClient client = new OkHttpClient.Builder().connectTimeout(15, TimeUnit.SECONDS).build();
client.newCall(requestbuilder.url(url).build()).enqueue(new Callback() {
@Override
public void onFailure(Call call, IOException e) {
future.completeExceptionally(e);
}
@Override
public void onResponse(Call call, Response response) {
try {
ResponseBody body = response.body();
if (response.code() != 200 || body == null) {
throw new IOException("Http error");
} else {
future.complete(body.string());
}
} catch (IOException | JsonSyntaxException e) {
future.completeExceptionally(e);
}
}
});
return future;
}
Then add a generic method to make the calls and deserialize the results:
private <T> Future<T> callAndDeserialize(String url, Gson gson, TypeToken<T> typeToken) {
CompletableFuture<String> future = call(url);
return future.thenApply(new Function<String, T>() {
public T apply(String body) {
return gson.fromJson(body, typeToken.getType()));
}
});
}
The loadRepository code would then be something like:
final Gson gson = new GsonBuilder().registerTypeHierarchyAdapter(Calendar.class, new CalendarGson()).create();
Future<List<Article>> articlesFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<List<Event>> eventsFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Event>>() {});
Future<List<Article>> sportsFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<List<Article>> fitnessFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<List<Article>> governmentFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<List<Article>>() {});
Future<Article> mainArticleFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<Article>() {});
Future<Configuration> configurationFuture = callAndDeserialize("https://apiurlarticles", gson, new TypeToken<Configuration>() {});
try {
articles = articlesFuture.get();
events = eventsFuture.get();
sportArticles = sportsFuture.get();
fitnessArticles = fitnessFuture.get();
governmentArticles = governmentFuture.get();
mainArticle = mainArticleFuture.get();
config = configurationFuture.get();
notifyObservers(HTTPRequestStatus.OK);
} catch (ExecutionException e) {
if(e.getCause() instanceof KeyManagementException || e.getCause() instanceof NoSuchAlgorithmException || e.getCause() instanceof KeyStoreException) {
notifyObservers(HTTPRequestStatus.TLSERROR);
} else {
notifyObservers(HTTPRequestStatus.HTTPERROR);
}
}
The ExecutionException at the end now retains the exception messages, causes and stacktraces. In case there's any unexpected errors you need to debug, you can also log this exception as well notifying the observers.
answered 20 hours ago
fgb
48538
answered 20 hours ago
fgb
48538
answered 20 hours ago
fgb
48538
answered 20 hours ago
fgb
48538
48538
add a comment |
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2
Simplicity isn't usually the way to go here. I recommend you show the rest of your code. You might get different answers based on the less "simple" code than you would with what you currently have. Also please change the title to describe What your code Does as apposed to your goal. (Almost everyone wants to refactor their code.)
– bruglesco
Dec 27 '18 at 19:36
@bruglesco The difference between this code and the actual one is that there are like 10
RequestObjects and 10client.newCalls(request), should I include them anyway?– Exprove
Dec 27 '18 at 20:55
Yes. You should.
– bruglesco
Dec 27 '18 at 21:17