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
   * <p>
   * http://www.apache.org/licenses/LICENSE-2.0
   * <p>
   * 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.atlas.notification.spool.utils.local;
  
  import org.apache.commons.lang.StringUtils;
  
  import java.io.DataInput;
  import java.io.DataOutput;
  import java.io.File;
  import java.io.IOException;
  import java.io.RandomAccessFile;
  import java.nio.channels.FileChannel;
  import java.nio.channels.FileLock;
  
  public class FileLockedReadWrite extends FileOperation {
      private RandomAccessFile raf;
      private FileChannel      channel;
      private FileLock         lock;
  
      public FileLockedReadWrite(String source) {
          super(source);
      }
  
      @Override
      public FileLock run(RandomAccessFile randomAccessFile, FileChannel channel, String json) throws IOException {
          this.raf     = randomAccessFile;
          this.channel = channel;
          this.lock    = channel.tryLock();
  
          return lock;
      }
  
      public DataInput getInput(File file) throws IOException {
          return getRaf(file);
      }
  
      public DataOutput getOutput(File file) throws IOException {
          return getRaf(file);
      }
  
      public void flush() throws IOException {
          if (channel != null) {
              channel.force(true);
          }
      }
  
      public void close() {
          super.close(this.raf, this.channel, this.lock);
      }
  
      private RandomAccessFile getRaf(File file) throws IOException {
          RandomAccessFile raf = new RandomAccessFile(file, "rws");
  
          run(raf, raf.getChannel(), StringUtils.EMPTY);
  
          return raf;
      }
  }
  