[HADOOP-5571] TupleWritable can return incorrect results if it contains more than 32 values

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.19.1
• Fix Version/s: 0.20.0
• Hadoop Flags: Reviewed
• Assignee: Jingkei Ly
• Reporter: Jingkei Ly
• Created: 25/Mar/09 12:55
• Updated: 08/Jul/09 16:53
• Resolved: 27/Mar/09 06:22

Description

When attempting to do an outer join on 45 files with the CompositeInputFormat, I've been encountering unexpected results in the TupleWritable returned by the record reader. On closer inspection, it seems to be because TupleWritable.setWritten(int) is incorrectly setting some tuple positions as written, i.e when you set setWritten(42), it also sets position 10.

The following Junit test demonstrates the problem:

  public void testWideTuple() throws Exception {
    Text emptyText = new Text("Should be empty");
    Writable[] values = new Writable[64];
    Arrays.fill(values,emptyText);
    values[42] = new Text("Number 42");
                                     
    TupleWritable tuple = new TupleWritable(values);
    tuple.setWritten(42);
    
    for (int pos=0; pos<tuple.size();pos++) {
      boolean has = tuple.has(pos);
      if (pos == 42) {
        assertTrue(has);
      }
      else {
        assertFalse("Tuple position is incorrectly labelled as set: " + pos, has);
      }
    }
}

Similarly, TupleWritable.setWritten(9) also causes TupleWritable.has(41) to incorrectly return true.