| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.lucene.luke.models.util.twentynewsgroups; |
| |
| import java.io.BufferedReader; |
| import java.io.IOException; |
| import java.lang.invoke.MethodHandles; |
| import java.nio.charset.StandardCharsets; |
| import java.nio.file.FileVisitResult; |
| import java.nio.file.Files; |
| import java.nio.file.Path; |
| import java.nio.file.SimpleFileVisitor; |
| import java.nio.file.attribute.BasicFileAttributes; |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| import org.apache.logging.log4j.Logger; |
| import org.apache.lucene.luke.util.LoggerFactory; |
| |
| /** 20 Newsgroups (http://kdd.ics.uci.edu/databases/20newsgroups/20newsgroups.html) message files parser */ |
| public class MessageFilesParser extends SimpleFileVisitor<Path> { |
| |
| private static final Logger log = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass()); |
| |
| private final Path root; |
| |
| private final List<Message> messages = new ArrayList<>(); |
| |
| public MessageFilesParser(Path root) { |
| this.root = root; |
| } |
| |
| public FileVisitResult visitFile(Path file, BasicFileAttributes attr) { |
| try { |
| if (attr.isRegularFile()) { |
| Message message = parse(file); |
| if (message != null) { |
| messages.add(parse(file)); |
| } |
| } |
| } catch (IOException e) { |
| log.warn("Invalid file? {}", file); |
| } |
| return FileVisitResult.CONTINUE; |
| } |
| |
| Message parse(Path file) throws IOException { |
| try (BufferedReader br = Files.newBufferedReader(file, StandardCharsets.UTF_8)) { |
| String line = br.readLine(); |
| |
| Message message = new Message(); |
| while (!line.equals("")) { |
| String[] ary = line.split(":", 2); |
| if (ary.length < 2) { |
| line = br.readLine(); |
| continue; |
| } |
| String att = ary[0].trim(); |
| String val = ary[1].trim(); |
| switch (att) { |
| case "From": |
| message.setFrom(val); |
| break; |
| case "Newsgroups": |
| message.setNewsgroups(val.split(",")); |
| break; |
| case "Subject": |
| message.setSubject(val); |
| break; |
| case "Message-ID": |
| message.setMessageId(val); |
| break; |
| case "Date": |
| message.setDate(val); |
| break; |
| case "Organization": |
| message.setOrganization(val); |
| break; |
| case "Lines": |
| try { |
| message.setLines(Integer.parseInt(ary[1].trim())); |
| } catch (NumberFormatException e) {} |
| break; |
| default: |
| break; |
| } |
| |
| line = br.readLine(); |
| } |
| |
| StringBuilder sb = new StringBuilder(); |
| while (line != null) { |
| sb.append(line); |
| sb.append(" "); |
| line = br.readLine(); |
| } |
| message.setBody(sb.toString()); |
| |
| return message; |
| } |
| } |
| |
| public List<Message> parseAll() throws IOException { |
| Files.walkFileTree(root, this); |
| return messages; |
| } |
| |
| } |