Java tutorial
/* * Overchan Android (Meta Imageboard Client) * Copyright (C) 2014-2016 miku-nyan <https://github.com/miku-nyan> * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * 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. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package nya.miku.wishmaster.chans.krautchan; import java.io.BufferedReader; import java.io.Closeable; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.Reader; import java.util.ArrayList; import java.util.List; import org.apache.commons.lang3.StringEscapeUtils; import nya.miku.wishmaster.api.models.AttachmentModel; import nya.miku.wishmaster.api.models.BadgeIconModel; import nya.miku.wishmaster.api.models.PostModel; import nya.miku.wishmaster.api.models.ThreadModel; import nya.miku.wishmaster.api.util.RegexUtils; public class KrautCatalogReader implements Closeable { private static final char[] CATALOG_START = "<article".toCharArray(); private static final char[] SECTION_OPEN = "<section>".toCharArray(); private static final char[] SECTION_CLOSE = "</section>".toCharArray(); private static final int FILTER_THREAD_NUMBER = 0; private static final int FILTER_THREAD_TITLE = 1; private static final int FILTER_THUMBNAIL = 2; private static final int FILTER_OMITTED = 3; private static final int FILTER_POST = 4; private static final int FILTER_THREAD_END = 5; public static final char[][] FILTERS_OPEN = { "class=\"thread_OP\" id=\"".toCharArray(), "<header>".toCharArray(), "<img src=\"/thumbnails/".toCharArray(), "<span class=\"omitted_text\">".toCharArray(), "<div class=\"post_text\">".toCharArray(), "</article>".toCharArray() }; private static final char[][] FILTERS_CLOSE = { "\"".toCharArray(), "</header>".toCharArray(), "\"".toCharArray(), "</span>".toCharArray(), null, null }; private final Reader _in; private StringBuilder readBuffer = new StringBuilder(); private List<ThreadModel> threads; private ThreadModel currentThread; private StringBuilder omittedDigitsBuffer = new StringBuilder(); public KrautCatalogReader(Reader reader) { _in = reader; } public KrautCatalogReader(InputStream in) { this(new BufferedReader(new InputStreamReader(in))); } public ThreadModel[] readPage() throws IOException { threads = new ArrayList<ThreadModel>(); initThreadModel(); skipUntilSequence(CATALOG_START); readData(); return threads.toArray(new ThreadModel[threads.size()]); } private void readData() throws IOException { int filtersCount = FILTERS_OPEN.length; int[] pos = new int[filtersCount]; int[] len = new int[filtersCount]; for (int i = 0; i < filtersCount; ++i) len[i] = FILTERS_OPEN[i].length; int curChar; while ((curChar = _in.read()) != -1) { for (int i = 0; i < filtersCount; ++i) { if (curChar == FILTERS_OPEN[i][pos[i]]) { ++pos[i]; if (pos[i] == len[i]) { handleFilter(i); pos[i] = 0; } } else { if (pos[i] != 0) pos[i] = curChar == FILTERS_OPEN[i][0] ? 1 : 0; } } } finalizeThread(); } private void initThreadModel() { currentThread = new ThreadModel(); currentThread.postsCount = 0; currentThread.attachmentsCount = 0; currentThread.posts = new PostModel[1]; currentThread.posts[0] = new PostModel(); currentThread.posts[0].email = ""; currentThread.posts[0].trip = ""; currentThread.posts[0].name = ""; } private void finalizeThread() { if (currentThread.posts[0].number != null && currentThread.posts[0].number.length() > 0) { currentThread.threadNumber = currentThread.posts[0].number; currentThread.posts[0].parentThread = currentThread.posts[0].number; if (currentThread.posts[0].subject == null) currentThread.posts[0].subject = ""; if (currentThread.posts[0].comment == null) currentThread.posts[0].comment = ""; if (currentThread.posts[0].attachments == null) currentThread.posts[0].attachments = new AttachmentModel[0]; threads.add(currentThread); } initThreadModel(); } private void handleFilter(int filterIndex) throws IOException { switch (filterIndex) { case FILTER_THREAD_NUMBER: currentThread.posts[0].number = readUntilSequence(FILTERS_CLOSE[filterIndex]); break; case FILTER_THREAD_TITLE: String headerHtml = readUntilSequence(FILTERS_CLOSE[filterIndex]); int countryBallIndex = headerHtml.indexOf("<img class=\"post_country\" src=\"/images/balls/"); if (countryBallIndex == -1) { countryBallIndex = headerHtml.indexOf("<img class=\"post_country\" src=\"/images/warballs/"); } if (countryBallIndex != -1) { int start = countryBallIndex + 31; int end = headerHtml.indexOf('\"', start); if (end != -1) { BadgeIconModel icon = new BadgeIconModel(); icon.source = headerHtml.substring(start, end); currentThread.posts[0].icons = new BadgeIconModel[] { icon }; } } currentThread.posts[0].subject = StringEscapeUtils.unescapeHtml4(RegexUtils.removeHtmlTags(headerHtml)) .trim(); break; case FILTER_THUMBNAIL: AttachmentModel attachment = new AttachmentModel(); attachment.type = AttachmentModel.TYPE_IMAGE_STATIC; attachment.size = -1; attachment.width = -1; attachment.height = -1; attachment.thumbnail = "/thumbnails/" + readUntilSequence(FILTERS_CLOSE[filterIndex]); attachment.path = attachment.thumbnail.replace("/thumbnails/", "/files/"); currentThread.posts[0].attachments = new AttachmentModel[] { attachment }; break; case FILTER_OMITTED: parseOmittedString(readUntilSequence(FILTERS_CLOSE[filterIndex])); break; case FILTER_POST: skipUntilSequence(SECTION_OPEN); currentThread.posts[0].comment = readUntilSequence(SECTION_CLOSE); break; case FILTER_THREAD_END: finalizeThread(); break; } } private void parseOmittedString(String omitted) { int postsOmitted = -1; try { int len = omitted.length(); for (int i = 0; i <= len; ++i) { char ch = i == len ? ' ' : omitted.charAt(i); if (ch >= '0' && ch <= '9') { omittedDigitsBuffer.append(ch); } else { if (omittedDigitsBuffer.length() > 0) { int parsedValue = Integer.parseInt(omittedDigitsBuffer.toString()); omittedDigitsBuffer.setLength(0); if (postsOmitted == -1) { postsOmitted = parsedValue; break; } } } } } catch (NumberFormatException e) { } if (postsOmitted > 0) currentThread.postsCount = 1 + postsOmitted; } private void skipUntilSequence(char[] sequence) throws IOException { int len = sequence.length; if (len == 0) return; int pos = 0; int curChar; while ((curChar = _in.read()) != -1) { if (curChar == sequence[pos]) { ++pos; if (pos == len) break; } else { if (pos != 0) pos = curChar == sequence[0] ? 1 : 0; } } } private String readUntilSequence(char[] sequence) throws IOException { int len = sequence.length; if (len == 0) return ""; readBuffer.setLength(0); int pos = 0; int curChar; while ((curChar = _in.read()) != -1) { readBuffer.append((char) curChar); if (curChar == sequence[pos]) { ++pos; if (pos == len) break; } else { if (pos != 0) pos = curChar == sequence[0] ? 1 : 0; } } int buflen = readBuffer.length(); if (buflen >= len) { readBuffer.setLength(buflen - len); return readBuffer.toString(); } else { return ""; } } @Override public void close() throws IOException { _in.close(); } }