Android Open Source - AndroidMooch J S O N Util

• Back to Development/book  ↑

From Project

Back to project page AndroidMooch.

License

The source code is released under:

Copyright (c) 2010 Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software witho...

Java Source Code

package com.github.stchris.util;
//  w  ww  .  j a  v  a2  s .c o m
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;
import java.util.List;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.util.Log;

import com.github.stchris.models.Book;
import com.github.stchris.queries.Constants;

/**
 * JSON handlers and parsers.
 * 
 * @author chris
 * 
 */
public class JSONUtil {

  /**
   * Logging tag.
   */
  private static final String TAG = "JSONUtil";

  /**
   * Call the asin service and get book information for one book.
   * 
   * @param asin
   *            the amazon id or ISBN of the book to query
   * @return Book model
   */
  public static Book getBookInfo(String asin) {
    if (asin == null || "".equals(asin.trim())) {
      return new Book();
    }
    return getBooksInfoFromJSON(getJSON(Constants.ASINS_URL.replace(
        Constants.ASINS_URL_PLACEHOLDER, asin)))[0];
  }

  public static Book[] searchBooks(String query, String db) {
    if (query == null || "".equals(query.trim())) {
      return null;
    }
    String url = Constants.SEARCH_URL.replace(Constants.SEARCH_URL_DB, db);
    url = url.replace(Constants.SEARCH_URL_QUERY, query);
    return getBooksInfoFromJSON(getJSON(url));
  }

  /**
   * Parse the given JSON and fill a Book model entry.
   * 
   * @param json
   *            book info
   * @return Book model
   */
  private static Book[] getBooksInfoFromJSON(String json) {
    List<Book> books = new ArrayList<Book>();
    try {
      JSONArray arr = new JSONArray(json);
      for (int i = 0; i < arr.length(); i++) {
        JSONObject bookJSON = arr.getJSONObject(i);
        Book book = new Book();
        book.author = safeGet(bookJSON, Constants.KEY_AUTHOR);
        book.title = safeGet(bookJSON, Constants.KEY_TITLE);
        book.publisher = safeGet(bookJSON, Constants.KEY_PUBLISHER);
        book.publicationDate = safeGet(bookJSON, Constants.KEY_PUBLICATION_DATE);
        book.numberOfPages = safeGet(bookJSON, Constants.KEY_NUMBER_OF_PAGES);
        book.binding = safeGet(bookJSON, Constants.KEY_BINDING);
        book.store = safeGet(bookJSON, Constants.KEY_STORE);
        book.price = safeGet(bookJSON, Constants.KEY_PRICE);
        book.currency = safeGet(bookJSON, Constants.KEY_CURRENCY);
        book.smallImgUrl = safeGet(bookJSON, Constants.KEY_SMALLIMG_URL);
        book.smallImgHeight = safeGet(bookJSON, Constants.KEY_SMALLIMG_HEIGHT);
        book.smallImgWidth = safeGet(bookJSON, Constants.KEY_SMALLIMG_WIDTH);
        book.largeImgUrl = safeGet(bookJSON, Constants.KEY_LARGEIMG_URL);
        book.largeImgHeight = safeGet(bookJSON, Constants.KEY_LARGEIMG_HEIGHT);
        book.largeImgWidth = safeGet(bookJSON, Constants.KEY_LARGEIMG_WIDTH);
        book.isbn = safeGet(bookJSON, Constants.KEY_ISBN);
        books.add(book);
      }
    } catch (JSONException e) {
      e.printStackTrace();
    }

    return books.toArray(new Book[0]);
  }

  /**
   * Request JSON from a given URL.
   * 
   * @param url
   *            String
   * @return result as {@link String}
   */
  private static String getJSON(String url) {
    StringBuffer res = new StringBuffer();

    try {
      // Perform action on click
      URLConnection conn = new URL(url).openConnection();
      // Get the response
      BufferedReader rd = new BufferedReader(new InputStreamReader(conn
          .getInputStream()));
      String line = "";
      while ((line = rd.readLine()) != null) {
        res.append(line);
      }
    } catch (Exception e) {
      System.err.println(e);
    }

    return res.toString();
  }
  
  /**
   * Get a key from an object, but return an empty String if it's not found. 
   * 
   * @param obj {@link JSONObject} to query
   * @param key key to look for
   * @return String with result
   */
  private static String safeGet(JSONObject obj, String key) {
    if (obj.has(key))  {
      try {
        return obj.getString(key);
      } catch (JSONException e) {
        Log.e(TAG, e.getMessage());
        return "";
      }
    } else {
      return "";
    }
  }
}

Java Source Code List

• Back to Development/book  ↑