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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *     http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing, software
13   * distributed under the License is distributed on an "AS IS" BASIS,
14   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15   * See the License for the specific language governing permissions and
16   * limitations under the License.
17   */
18  
19  package org.apache.hadoop.chukwa;
20  
21  
22  import java.util.*;
23  import org.apache.hadoop.io.DataOutputBuffer;
24  import java.io.*;
25  
26  /**
27   * Right now, just handles record collection.
28   * 
29   */
30  public class ChunkBuilder {
31  
32    ArrayList<Integer> recOffsets = new ArrayList<Integer>();
33    int lastRecOffset = -1;
34    DataOutputBuffer buf = new DataOutputBuffer();
35  
36    /**
37     * Adds the data in rec to an internal buffer; rec can be reused immediately.
38     * 
39     * @param rec
40     */
41    public void addRecord(byte[] rec) {
42      lastRecOffset = lastRecOffset + rec.length;
43      recOffsets.add(lastRecOffset);
44      try {
45        buf.write(rec);
46      } catch (IOException e) {
47        throw new RuntimeException("buffer write failed.  Out of memory?", e);
48      }
49    }
50  
51    public Chunk getChunk() {
52      ChunkImpl c = new ChunkImpl();
53      c.setData(buf.getData());
54      c.setSeqID(buf.getLength());
55      int[] offsets = new int[recOffsets.size()];
56      for (int i = 0; i < offsets.length; ++i)
57        offsets[i] = recOffsets.get(i);
58      c.setRecordOffsets(offsets);
59  
60      return c;
61    }
62  
63  }