Java tutorial
/* * Tint Browser for Android * * Copyright (C) 2012 - to infinity and beyond J. Devauchelle and contributors. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * version 3 as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ package com.acrutiapps.browser.tasks; import java.io.File; import java.io.FileWriter; import java.io.IOException; import java.net.URLEncoder; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Locale; import org.json.JSONArray; import org.json.JSONException; import org.json.JSONObject; import com.acrutiapps.browser.R; import com.acrutiapps.browser.providers.BookmarksProvider; import com.acrutiapps.browser.ui.preferences.IHistoryBookmaksExportListener; import com.acrutiapps.browser.utils.IOUtils; import android.content.Context; import android.database.Cursor; import android.os.AsyncTask; import android.os.Environment; public class HistoryBookmarksExportTask extends AsyncTask<Cursor, Integer, String> { private Context mContext; private IHistoryBookmaksExportListener mListener; public HistoryBookmarksExportTask(Context context, IHistoryBookmaksExportListener listener) { mContext = context; mListener = listener; } @Override protected String doInBackground(Cursor... params) { publishProgress(0, 0, 0); String cardState = IOUtils.checkCardState(mContext); if (cardState != null) { return cardState; } return writeAsJSON(params); } @Override protected void onProgressUpdate(Integer... values) { mListener.onExportProgress(values[0], values[1], values[2]); } @Override protected void onPostExecute(String result) { mListener.onExportDone(result); } /** * Get a string representation of the current date / time in a format suitable for a file name. * @return A string representation of the current date / time. */ private String getNowForFileName() { Calendar c = Calendar.getInstance(); SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd-HHmmss", Locale.US); return sdf.format(c.getTime()); } private String writeAsJSON(Cursor... params) { try { String fileName = mContext.getString(R.string.ApplicationName) + "-" + getNowForFileName() + ".json"; File file = new File(Environment.getExternalStorageDirectory(), fileName); FileWriter writer = new FileWriter(file); FoldersJSONArray foldersArray = new FoldersJSONArray(); BookmarksJSONArray bookmarksArray = new BookmarksJSONArray(); HistoryJSONArray historyArray = new HistoryJSONArray(); Cursor c = params[0]; if (c.moveToFirst()) { int current = 0; int total = c.getCount(); int idIndex = c.getColumnIndex(BookmarksProvider.Columns._ID); int titleIndex = c.getColumnIndex(BookmarksProvider.Columns.TITLE); int urlIndex = c.getColumnIndex(BookmarksProvider.Columns.URL); int creationDateIndex = c.getColumnIndex(BookmarksProvider.Columns.CREATION_DATE); int visitedDateIndex = c.getColumnIndex(BookmarksProvider.Columns.VISITED_DATE); int visitsIndex = c.getColumnIndex(BookmarksProvider.Columns.VISITS); int bookmarkIndex = c.getColumnIndex(BookmarksProvider.Columns.BOOKMARK); int folderIndex = c.getColumnIndex(BookmarksProvider.Columns.IS_FOLDER); int parentfolderIdIndex = c.getColumnIndex(BookmarksProvider.Columns.PARENT_FOLDER_ID); while (!c.isAfterLast()) { publishProgress(1, current, total); boolean isFolder = c.getInt(folderIndex) > 0 ? true : false; if (isFolder) { String title = c.getString(titleIndex); title = title != null ? URLEncoder.encode(title, "UTF-8") : ""; foldersArray.add(title, c.getLong(idIndex), c.getLong(parentfolderIdIndex)); } else { boolean isBookmark = c.getInt(bookmarkIndex) > 0 ? true : false; String title = c.getString(titleIndex); title = title != null ? URLEncoder.encode(title, "UTF-8") : ""; String url = c.getString(urlIndex); url = url != null ? URLEncoder.encode(url, "UTF-8") : ""; if (isBookmark) { bookmarksArray.add(c.getLong(parentfolderIdIndex), title, url, c.getLong(creationDateIndex), c.getLong(visitedDateIndex), c.getInt(visitsIndex)); } else { historyArray.add(title, url, c.getLong(visitedDateIndex), c.getInt(visitsIndex)); } } current++; c.moveToNext(); } } JSONObject output = new JSONObject(); output.put("folders", foldersArray); output.put("bookmarks", bookmarksArray); output.put("history", historyArray); writer.write(output.toString(1)); writer.flush(); writer.close(); } catch (JSONException e) { e.printStackTrace(); return e.getMessage(); } catch (IOException e) { e.printStackTrace(); return e.getMessage(); } return null; } private class FoldersJSONArray extends JSONArray { public void add(String title, long id, long parentId) throws JSONException { JSONObject item = new JSONObject(); item.put("title", title); item.put("id", id); item.put("parentId", parentId); this.put(item); } } private class BookmarksJSONArray extends JSONArray { public void add(long folderId, String title, String url, long creationDate, long visitedDate, int visits) throws JSONException { JSONObject item = new JSONObject(); item.put("folderId", folderId); item.put("title", title); item.put("url", url); item.put("creationDate", creationDate); item.put("visitedDate", visitedDate); item.put("visits", visits); this.put(item); } } private class HistoryJSONArray extends JSONArray { public void add(String title, String url, long visitedDate, int visits) throws JSONException { JSONObject item = new JSONObject(); item.put("title", title); item.put("url", url); item.put("visitedDate", visitedDate); item.put("visits", visits); this.put(item); } } }