content: /**
   * 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 com.alibaba.jstorm.blobstore;
  
  
  import backtype.storm.generated.SettableBlobMeta;
  
  import java.io.*;
  import java.nio.file.Files;
  import java.nio.file.StandardCopyOption;
  import java.util.regex.Matcher;
  
  public class LocalFsBlobStoreFile extends BlobStoreFile {
  
      private final String _key;
      private final boolean _isTmp;
      private final File _path;
      private Long _modTime = null;
      private final boolean _mustBeNew;
      private SettableBlobMeta meta;
  
      public LocalFsBlobStoreFile(File base, String name) {
          if (BlobStoreFile.BLOBSTORE_DATA_FILE.equals(name)) {
              _isTmp = false;
          } else {
              Matcher m = TMP_NAME_PATTERN.matcher(name);
              if (!m.matches()) {
                  throw new IllegalArgumentException("File name does not match '"+name+"' !~ "+TMP_NAME_PATTERN);
              }
              _isTmp = true;
          }
          _key = base.getName();
          _path = new File(base, name);
          _mustBeNew = false;
      }
  
      public LocalFsBlobStoreFile(File base, boolean isTmp, boolean mustBeNew) {
          _key = base.getName();
          _isTmp = isTmp;
          _mustBeNew = mustBeNew;
          if (_isTmp) {
              _path = new File(base, System.currentTimeMillis()+TMP_EXT);
          } else {
              _path = new File(base, BlobStoreFile.BLOBSTORE_DATA_FILE);
          }
      }
  
      @Override
      public void delete() throws IOException {
          _path.delete();
      }
  
      @Override
      public boolean isTmp() {
          return _isTmp;
      }
  
      @Override
      public String getKey() {
          return _key;
      }
  
      @Override
      public long getModTime() throws IOException {
          if (_modTime == null) {
              _modTime = _path.lastModified();
          }
          return _modTime;
      }
  
      @Override
      public InputStream getInputStream() throws IOException {
          if (isTmp()) {
              throw new IllegalStateException("Cannot read from a temporary part file.");
          }
          return new FileInputStream(_path);
      }
  
      @Override
      public OutputStream getOutputStream() throws IOException {
          if (!isTmp()) {
              throw new IllegalStateException("Can only write to a temporary part file.");
          }
          boolean success;
          try {
              success = _path.createNewFile();
          } catch (IOException e) {
              //Try to create the parent directory, may not work
              _path.getParentFile().mkdirs();
              success = _path.createNewFile();
          }
          if (!success) {
              throw new IOException(_path+" already exists");
          }
          return new FileOutputStream(_path);
      }
  
      @Override
      public void commit() throws IOException {
          if (!isTmp()) {
              throw new IllegalStateException("Can only write to a temporary part file.");
          }
  
          File dest = new File(_path.getParentFile(), BlobStoreFile.BLOBSTORE_DATA_FILE);
          if (_mustBeNew) {
              Files.move(_path.toPath(), dest.toPath(), StandardCopyOption.ATOMIC_MOVE);
          } else {
              Files.move(_path.toPath(), dest.toPath(), StandardCopyOption.ATOMIC_MOVE, StandardCopyOption.REPLACE_EXISTING);
          }
      }
  
      @Override
      public void cancel() throws IOException {
          if (!isTmp()) {
              throw new IllegalStateException("Can only write to a temporary part file.");
          }
          delete();
      }
  
      @Override
      public SettableBlobMeta getMetadata () {
          return meta;
      }
  
      @Override
      public void setMetadata (SettableBlobMeta meta) {
          this.meta = meta;
      }
  
      @Override
      public String toString() {
          return _path+":"+(_isTmp ? "tmp": BlobStoreFile.BLOBSTORE_DATA_FILE)+":"+_key;
      }
  
      @Override
      public long getFileLength() {
          return _path.length();
      }
  }
  
  