| /* |
| * 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.iotdb.db.metadata.logfile; |
| |
| import org.apache.iotdb.db.engine.fileSystem.SystemFileFactory; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import java.io.BufferedReader; |
| import java.io.File; |
| import java.io.FileReader; |
| import java.io.IOException; |
| |
| /** reader for reading mlog.txt */ |
| public class MLogTxtReader implements AutoCloseable { |
| private static final Logger logger = LoggerFactory.getLogger(MLogTxtReader.class); |
| |
| private BufferedReader bufferedReader; |
| private File logFile; |
| private String cmd; |
| |
| public MLogTxtReader(String schemaDir, String logFileName) throws IOException { |
| File metadataDir = SystemFileFactory.INSTANCE.getFile(schemaDir); |
| if (!metadataDir.exists()) { |
| logger.error("no mlog.txt to init MManager."); |
| throw new IOException("mlog.txt does not exist."); |
| } |
| |
| logFile = SystemFileFactory.INSTANCE.getFile(schemaDir + File.separator + logFileName); |
| bufferedReader = new BufferedReader(new FileReader(logFile)); |
| } |
| |
| public String next() { |
| String ret = cmd; |
| cmd = null; |
| return ret; |
| } |
| |
| public boolean hasNext() { |
| if (cmd != null) { |
| return true; |
| } |
| try { |
| return (cmd = bufferedReader.readLine()) != null; |
| } catch (IOException e) { |
| logger.warn("Read mlog error."); |
| cmd = null; |
| return false; |
| } |
| } |
| |
| @Override |
| public void close() { |
| try { |
| bufferedReader.close(); |
| } catch (IOException e) { |
| logger.error("Failed to close mlog.txt"); |
| } |
| } |
| } |