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.BufferedReader; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStreamReader; import java.io.UnsupportedEncodingException; import java.net.URLDecoder; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Locale; import java.util.Map; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.ParserConfigurationException; import org.json.JSONArray; import org.json.JSONException; import org.json.JSONObject; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.Node; import org.w3c.dom.NodeList; import org.xml.sax.SAXException; import com.acrutiapps.browser.R; import com.acrutiapps.browser.providers.BookmarksProvider; import com.acrutiapps.browser.ui.preferences.IHistoryBookmaksImportListener; import android.content.ContentValues; import android.content.Context; import android.net.Uri; import android.os.AsyncTask; import android.os.Environment; public class HistoryBookmarksImportTask extends AsyncTask<String, Integer, String> { private Context mContext; private IHistoryBookmaksImportListener mListener; public HistoryBookmarksImportTask(Context context, IHistoryBookmaksImportListener listener) { mContext = context; mListener = listener; } @Override protected String doInBackground(String... params) { publishProgress(0, 0, 0); File file = new File(Environment.getExternalStorageDirectory(), params[0]); if ((file != null) && (file.exists()) && (file.canRead())) { if (file.getName().toLowerCase(Locale.US).endsWith(".json")) { return readAsJSON(file); } else if (file.getName().toLowerCase(Locale.US).endsWith(".xml")) { return readAsXml(file); } else { return mContext.getString(R.string.HistoryBookmarksImportErrorInvalidFileFormat); } } else { return mContext.getString(R.string.HistoryBookmarksImportFileUnavailable); } } @Override protected void onProgressUpdate(Integer... values) { mListener.onImportProgress(values[0], values[1], values[2]); } @Override protected void onPostExecute(String result) { mListener.onImportDone(result); } private String readAsJSON(File file) { List<ContentValues> insertValues = null; try { insertValues = new ArrayList<ContentValues>(); publishProgress(1, 0, 0); FileInputStream fis = new FileInputStream(file); StringBuilder sb = new StringBuilder(); String line; BufferedReader reader; try { reader = new BufferedReader(new InputStreamReader(fis, "UTF-8")); while ((line = reader.readLine()) != null) { sb.append(line); } } catch (UnsupportedEncodingException e) { e.printStackTrace(); return e.getMessage(); } catch (IOException e) { e.printStackTrace(); return e.getMessage(); } finally { try { fis.close(); } catch (IOException e) { e.printStackTrace(); return e.getMessage(); } } JSONObject data = new JSONObject(sb.toString()); Map<Long, Folder> folders = new HashMap<Long, Folder>(); if (data.has("folders")) { JSONArray foldersArray = data.getJSONArray("folders"); int progress = 0; int total = foldersArray.length(); for (int i = 0; i < foldersArray.length(); i++) { publishProgress(3, progress, total); JSONObject folder = foldersArray.getJSONObject(i); long id = folder.getLong("id"); long parentId = folder.getLong("parentId"); String title = URLDecoder.decode(folder.getString("title"), "UTF-8"); ContentValues values = new ContentValues(); values.put(BookmarksProvider.Columns.TITLE, title); values.put(BookmarksProvider.Columns.BOOKMARK, 0); values.put(BookmarksProvider.Columns.IS_FOLDER, 1); values.put(BookmarksProvider.Columns.PARENT_FOLDER_ID, -1); Uri insertionUri = mContext.getContentResolver().insert(BookmarksProvider.BOOKMARKS_URI, values); String insertionString = insertionUri.toString(); // Get the new id for the current folder. long insertionId = -1; try { insertionId = Long .parseLong(insertionString.substring(insertionString.lastIndexOf('/') + 1)); } catch (NumberFormatException e) { insertionId = -1; } // Keep a relation between the id of the folder in the export file, its parent id (in the export file), and its new id. folders.put(id, new Folder(insertionId, parentId)); progress++; } publishProgress(4, 0, 0); // Correct folders parent ids. if (!folders.isEmpty()) { for (Folder folder : folders.values()) { // For each folder previously inserted, check if it had a parent folder in the export file. long oldParentId = folder.getOldParentId(); if (oldParentId != -1) { // Get the parent folder by its old Id, key of folders map. Folder parentFolder = folders.get(oldParentId); if (parentFolder != null) { ContentValues values = new ContentValues(); values.put(BookmarksProvider.Columns.PARENT_FOLDER_ID, parentFolder.getNewId()); String whereClause = BookmarksProvider.Columns._ID + " = " + folder.getNewId(); mContext.getContentResolver().update(BookmarksProvider.BOOKMARKS_URI, values, whereClause, null); } } } } } if (data.has("bookmarks")) { JSONArray bookmarksArray = data.getJSONArray("bookmarks"); int progress = 0; int total = bookmarksArray.length(); for (int i = 0; i < bookmarksArray.length(); i++) { publishProgress(5, progress, total); JSONObject bookmark = bookmarksArray.getJSONObject(i); long folderId = bookmark.getLong("folderId"); Folder parentFolder = null; if (folderId != -1) { parentFolder = folders.get(folderId); } String title = URLDecoder.decode(bookmark.getString("title"), "UTF-8"); String url = URLDecoder.decode(bookmark.getString("url"), "UTF-8"); ContentValues values = createContentValues(title, url, bookmark.getInt("visits"), bookmark.getLong("visitedDate"), bookmark.getLong("creationDate"), 1); if (parentFolder != null) { values.put(BookmarksProvider.Columns.PARENT_FOLDER_ID, parentFolder.getNewId()); } insertValues.add(values); progress++; } } if (data.has("history")) { JSONArray historyArray = data.getJSONArray("history"); int progress = 0; int total = historyArray.length(); for (int i = 0; i < historyArray.length(); i++) { publishProgress(6, progress, total); JSONObject history = historyArray.getJSONObject(i); String title = URLDecoder.decode(history.getString("title"), "UTF-8"); String url = URLDecoder.decode(history.getString("url"), "UTF-8"); ContentValues values = createContentValues(title, url, history.getInt("visits"), history.getLong("visitedDate"), 0, 0); insertValues.add(values); progress++; } } } catch (FileNotFoundException e) { e.printStackTrace(); return e.getMessage(); } catch (JSONException e) { e.printStackTrace(); return e.getMessage(); } catch (UnsupportedEncodingException e) { e.printStackTrace(); return e.getMessage(); } if (insertValues != null) { publishProgress(7, 0, 0); mContext.getContentResolver().bulkInsert(BookmarksProvider.BOOKMARKS_URI, insertValues.toArray(new ContentValues[insertValues.size()])); } return null; } private String readAsXml(File file) { List<ContentValues> values = null; try { publishProgress(1, 0, 0); values = new ArrayList<ContentValues>(); DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); DocumentBuilder builder; builder = factory.newDocumentBuilder(); Document document = builder.parse(file); Element root = document.getDocumentElement(); if ((root != null) && (root.getNodeName().equals("itemlist"))) { NodeList itemsList = root.getElementsByTagName("item"); int progress = 0; int total = itemsList.getLength(); Node item; NodeList record; Node dataItem; for (int i = 0; i < itemsList.getLength(); i++) { publishProgress(2, progress, total); item = itemsList.item(i); if (item != null) { record = item.getChildNodes(); String title = null; String url = null; int visits = 0; long visitedDate = -1; long creationDate = -1; int bookmark = 0; for (int j = 0; j < record.getLength(); j++) { dataItem = record.item(j); if ((dataItem != null) && (dataItem.getNodeName() != null)) { if (dataItem.getNodeName().equals("title")) { title = URLDecoder.decode(getNodeContent(dataItem), "UTF-8"); } else if (dataItem.getNodeName().equals("url")) { url = URLDecoder.decode(getNodeContent(dataItem), "UTF-8"); } else if (dataItem.getNodeName().equals("visits")) { try { visits = Integer.parseInt(getNodeContent(dataItem)); } catch (Exception e) { visits = 0; } } else if (dataItem.getNodeName().equals("visiteddate")) { try { visitedDate = Long.parseLong(getNodeContent(dataItem)); } catch (Exception e) { visitedDate = -1; } } else if (dataItem.getNodeName().equals("creationdate")) { try { creationDate = Long.parseLong(getNodeContent(dataItem)); } catch (Exception e) { creationDate = -1; } } else if (dataItem.getNodeName().equals("bookmark")) { try { bookmark = Integer.parseInt(getNodeContent(dataItem)); } catch (Exception e) { bookmark = 0; } } } } values.add(createContentValues(title, url, visits, visitedDate, creationDate, bookmark)); } progress++; } } } catch (ParserConfigurationException e) { return e.getMessage(); } catch (SAXException e) { return e.getMessage(); } catch (IOException e) { return e.getMessage(); } if (values != null) { publishProgress(7, 0, 0); mContext.getContentResolver().bulkInsert(BookmarksProvider.BOOKMARKS_URI, values.toArray(new ContentValues[values.size()])); } return null; } /** * Get the content of a node, why Android does not include Node.getTextContent() ? * @param node The node. * @return The node content. */ private String getNodeContent(Node node) { StringBuffer buffer = new StringBuffer(); NodeList childList = node.getChildNodes(); for (int i = 0; i < childList.getLength(); i++) { Node child = childList.item(i); if (child.getNodeType() != Node.TEXT_NODE) { continue; // skip non-text nodes } buffer.append(child.getNodeValue()); } return buffer.toString(); } private ContentValues createContentValues(String title, String url, int visits, long visitedDate, long creationDate, int bookmark) { ContentValues values = new ContentValues(); values.put(BookmarksProvider.Columns.TITLE, title); values.put(BookmarksProvider.Columns.URL, url); values.put(BookmarksProvider.Columns.VISITS, visits); if (visitedDate > 0) { values.put(BookmarksProvider.Columns.VISITED_DATE, visitedDate); } else { values.putNull(BookmarksProvider.Columns.VISITED_DATE); } if (creationDate > 0) { values.put(BookmarksProvider.Columns.CREATION_DATE, creationDate); } else { values.putNull(BookmarksProvider.Columns.CREATION_DATE); } if (bookmark > 0) { values.put(BookmarksProvider.Columns.BOOKMARK, 1); } else { values.put(BookmarksProvider.Columns.BOOKMARK, 0); } return values; } /** * Store the new id of a folder, and its * old parent id. E.g. the parent id in the export file. */ private class Folder { private long mNewId; private long mOldParentId; public Folder(long newId, long oldParentId) { mNewId = newId; mOldParentId = oldParentId; } public long getNewId() { return mNewId; } public long getOldParentId() { return mOldParentId; } } }