[HADOOP-15109] TestDFSIO -read -random doesn't work on file sized 4GB

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 3.0.0-beta1
• Fix Version/s: 3.1.0
• Component/s: fs, test
• Assignee: Ajay Kumar
• Reporter: zhoutai.zt
• Created: 11/Dec/17 11:26
• Updated: 18/Dec/17 22:03
• Resolved: 18/Dec/17 21:27

Description

TestDFSIO -read -random throws IllegalArgumentException on 4GB file. The cause is:

private long nextOffset(long current) {
      if(skipSize == 0)
        return rnd.nextInt((int)(fileSize));
      if(skipSize > 0)
        return (current < 0) ? 0 : (current + bufferSize + skipSize);
      // skipSize < 0
      return (current < 0) ? Math.max(0, fileSize - bufferSize) :
                             Math.max(0, current + skipSize);
    }
  }

When filesize exceeds signed int, (int)(filesize) will be negative and cause Random.nextInt throws IllegalArgumentException("n must be positive").