// добавить продукт в базу json server
public static void add(ProductREST product) throws NotValidProductException, IOException {
try {
check(product); // рповеряем продукт
// connection к серверу
HttpURLConnection con = (HttpURLConnection) ((new URL(PRODUCT_URL).openConnection()));
con.setRequestMethod("POST"); // метод post для добавления
// генерируем запрос
StringBuilder urlParameters = new StringBuilder();
urlParameters
.append("name=")
.append(URLEncoder.encode(product.getName(), "UTF8"))
.append("&");
urlParameters.append("price=").append(product.getPrice()).append("&");
urlParameters.append("weight=").append(product.getWeight()).append("&");
urlParameters
.append("manufacturer=")
.append(product.getManufacturer().getCountry())
.append("&");
urlParameters.append("category=").append(URLEncoder.encode(product.getCategory(), "UTF8"));
con.setDoOutput(true); // разрешаем отправку данных
// отправляем
try (DataOutputStream out = new DataOutputStream(con.getOutputStream())) {
out.writeBytes(urlParameters.toString());
}
// код ответа
int responseCode = con.getResponseCode();
System.out.println("\nSending 'POST' request to URL : " + PRODUCT_URL);
System.out.println("Response Code : " + responseCode);
} catch (NotValidProductException e) {
e.printStackTrace();
throw e;
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
throw new UnsupportedEncodingException("cannot recognize encoding");
} catch (ProtocolException e) {
e.printStackTrace();
throw new ProtocolException("No such protocol, protocol must be POST,DELETE,PATCH,GET etc.");
} catch (MalformedURLException e) {
e.printStackTrace();
throw new MalformedURLException("Url is not valid");
} catch (IOException e) {
e.printStackTrace();
throw new IOException("cannot write information to server");
}
}
// получит все продукты в виде спсика
public static List<ProductREST> getAll() throws IOException, JsonValidationException {
List<ProductREST> products = new LinkedList<>();
String data = readAll();
for (JsonElement e : getElements(data)) {
JsonObject obj = e.getAsJsonObject();
Iterator<Map.Entry<String, JsonElement>> elements = obj.entrySet().iterator();
int i = 0;
ProductREST current = new ProductREST();
while (elements.hasNext()) {
switch (i++) {
case 0:
current.setName(elements.next().getValue().getAsString());
break;
case 1:
current.setPrice(elements.next().getValue().getAsDouble());
break;
case 2:
current.setWeight(elements.next().getValue().getAsDouble());
break;
case 3:
current.setManufacturer(
ProductREST.getManufacturer(elements.next().getValue().getAsString()));
break;
case 4:
current.setCategory(elements.next().getValue().getAsString());
break;
case 5:
current.setId(elements.next().getValue().getAsInt());
break;
default:
throw new JsonValidationException("cannot validate json database, check it!");
}
}
products.add(current);
}
return products;
}
// проверка валидности
private static void check(ProductREST product) throws NotValidProductException {
double EPS = 1E-9; // можно и с 0 сравнивать просто так нпаписал, интересно же =)
if (product == null) {
throw new NullPointerException("Product must not be null!");
}
if (product.getName() == null || "".equals(product.getName())) {
throw new NotValidProductException("Product name must not be empty");
}
if (product.getCategory() == null || "".equals(product.getName())) {
throw new NotValidProductException("category is not valid");
}
if (product.getPrice() <= EPS || product.getWeight() <= EPS) {
throw new NotValidProductException("Product weight and price must be more than zero");
}
}
// получение в виде таблицы
public static String[][] getTable() {
List<ProductREST> products = new ArrayList<>();
try {
products = getAll();
} catch (IOException | JsonValidationException e) {
e.printStackTrace();
}
String[][] result = new String[products.size()][5];
int i = 0;
for (ProductREST p : products) {
result[i][0] = p.getName();
result[i][1] = String.valueOf(p.getPrice());
result[i][2] = String.valueOf(p.getWeight());
result[i][3] = p.getManufacturer().getCountry();
result[i][4] = p.getCategory(); // найти в категорияях по id name
i++;
}
return result;
}