data.GoogleBooksWS.java Source code

Introduction

Here is the source code for data.GoogleBooksWS.java

Source

package data;

import domain.Book;
import domain.Organization;
import domain.Person;
import domain.util.URIGenerator;
import java.net.HttpURLConnection;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;
import rdfmodel.RDFModel;

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

/**
 *
 * @author Stefan
 */
public class GoogleBooksWS extends WebService {

    private static final int RESULTS_PER_PAGE = 40;
    private int trenutniBrojStrane = 1;
    private int ukupanBrojStrana;
    private String baseUrl = "https://www.googleapis.com/books/v1/volumes?q=+subject:computers&maxResults=40&key=%20AIzaSyCfhdVI8zPi7BAL_UdlAb406nYnN6-hSks&startIndex=";
    private boolean prvi = true;
    private boolean kraj = false;

    @Override
    public void parse(String tekst) throws Exception {

        //List<Book> lista=new ArrayList<>();

        JSONParser parser = new JSONParser();
        Object obj = parser.parse(tekst);
        JSONObject jsonObject = (JSONObject) obj;
        if (prvi) {
            int brojRezultata = Integer.parseInt(jsonObject.get("totalItems") + "");
            ukupanBrojStrana = brojRezultata / RESULTS_PER_PAGE + 1;
            System.out.println("Broj strana" + ukupanBrojStrana);
            prvi = false;
        }

        System.out.println("Trenutni broj strane " + trenutniBrojStrane);
        JSONArray niz = (JSONArray) jsonObject.get("items");
        if (niz == null) {
            kraj = true;
        } else {
            Iterator iterator = niz.iterator();
            while (iterator.hasNext()) {
                Book b = new Book();
                b.setUri(URIGenerator.generateUri(b));
                JSONObject book = (JSONObject) iterator.next();
                b.setTitle((String) ((JSONObject) book.get("volumeInfo")).get("title"));
                JSONArray autori = (JSONArray) ((JSONObject) book.get("volumeInfo")).get("authors");
                if (autori != null) {
                    Iterator it = autori.iterator();
                    while (it.hasNext()) {
                        Person p = new Person();
                        p.setUri(URIGenerator.generateUri(p));
                        p.setName((String) it.next());
                        b.getAuthors().add(p);
                    }
                } else {
                    System.out.println("Autori su null");
                }
                Organization o = new Organization();
                o.setUri(URIGenerator.generateUri(o));
                o.setName((String) ((JSONObject) book.get("volumeInfo")).get("publisher"));
                b.setPublisher(o);
                String date = (String) ((JSONObject) book.get("volumeInfo")).get("publishedDate");
                System.out.println(date);
                b.setDatePublished(date);

                String description = (String) ((JSONObject) book.get("volumeInfo")).get("description");
                b.setDescription(description);

                Object brStr = ((JSONObject) book.get("volumeInfo")).get("pageCount");
                if (brStr != null) {
                    long broj = Long.parseLong(brStr.toString());
                    b.setNumberOfPages((int) broj);
                }

                JSONArray identifiers = (JSONArray) ((JSONObject) book.get("volumeInfo"))
                        .get("industryIdentifiers");
                if (identifiers != null) {
                    for (int i = 0; i < identifiers.size(); i++) {
                        JSONObject identifier = (JSONObject) identifiers.get(i);
                        if ("ISBN_13".equals((String) identifier.get("type"))) {
                            b.setIsbn((String) identifier.get("identifier"));
                        }
                    }
                }
                //b.setIsbn((String) ((JSONObject) ((JSONArray)((JSONObject)book.get("volumeInfo")).get("industryIdentifiers")).get(1)).get("identifier"));

                lista.add(b);

            }

            if (trenutniBrojStrane < ukupanBrojStrana) {
                trenutniBrojStrane++;
            } else {
                kraj = true;
            }
        }
    }

    @Override
    public String getUrl() {
        return baseUrl + izracunajStartIndex();
        //return "https://www.googleapis.com/books/v1/volumes?q=+subject:computers&maxResults=40&key=%20AIzaSyCfhdVI8zPi7BAL_UdlAb406nYnN6-hSks&startIndex=41";
        //return "https://www.googleapis.com/books/v1/volumes?q=+subject:computers&key=%20AIzaSyCfhdVI8zPi7BAL_UdlAb406nYnN6-hSks";
    }

    public int izracunajStartIndex() {
        return (trenutniBrojStrane - 1) * 40 + 1;
    }

    @Override
    public void setRequestType(HttpURLConnection conn) throws Exception {
        try {
            conn.setRequestMethod("GET");
        } catch (Exception e) {
            e.printStackTrace();
            throw e;
        }
    }

    @Override
    public void setDataType(HttpURLConnection conn) {
        conn.setRequestProperty("Accept", "application/json");
    }

    @Override
    public boolean daLiJeKraj() {
        return kraj;
    }

}