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.hdfs.bolt.rotation;
  
  
  import backtype.storm.tuple.Tuple;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * File rotation policy that will rotate files when a certain
   * file size is reached.
   *
   * For example:
   * <pre>
   *     // rotate when files reach 5MB
   *     FileSizeRotationPolicy policy =
   *          new FileSizeRotationPolicy(5.0, Units.MB);
   * </pre>
   *
   */
  public class FileSizeRotationPolicy implements FileRotationPolicy {
      private static final Logger LOG = LoggerFactory.getLogger(FileSizeRotationPolicy.class);
  
      public static enum Units {
  
          KB((long)Math.pow(2, 10)),
          MB((long)Math.pow(2, 20)),
          GB((long)Math.pow(2, 30)),
          TB((long)Math.pow(2, 40));
  
          private long byteCount;
  
          private Units(long byteCount){
              this.byteCount = byteCount;
          }
  
          public long getByteCount(){
              return byteCount;
          }
      }
  
      private long maxBytes;
  
      private long lastOffset = 0;
      private long currentBytesWritten = 0;
  
      public FileSizeRotationPolicy(float count, Units units){
          this.maxBytes = (long)(count * units.getByteCount());
      }
  
      @Override
      public boolean mark(Tuple tuple, long offset) {
          long diff = offset - this.lastOffset;
          this.currentBytesWritten += diff;
          this.lastOffset = offset;
          return this.currentBytesWritten >= this.maxBytes;
      }
  
      @Override
      public void reset() {
          this.currentBytesWritten = 0;
          this.lastOffset = 0;
      }
  
  }
  