IndexFile only 19999999 Indexes can be stored, not 20000000 Indexes

[ph3636]

1.describe :

class IndexHeader attribute indexCount initial value is 1 not 0，so index pos not begin 0 but begin 1，therefore IndexFile only 19999999 Indexes can be stored, not 20000000 Indexes

2. What did you see instead?
   class IndexHeader attribute indexCount as follows ：
   private AtomicInteger indexCount = new AtomicInteger(1);
   Original code as follows ：
   int absIndexPos = IndexHeader.INDEX_HEADER_SIZE + this.hashSlotNum * hashSlotSize
   + this.indexHeader.getIndexCount() * indexSize;
   this.mappedByteBuffer.putInt(absIndexPos, keyHash);
   this.mappedByteBuffer.putLong(absIndexPos + 4, phyOffset);
   this.mappedByteBuffer.putInt(absIndexPos + 4 + 8, (int) timeDiff);
   this.mappedByteBuffer.putInt(absIndexPos + 4 + 8 + 4, slotValue);
   this.mappedByteBuffer.putInt(absSlotPos, this.indexHeader.getIndexCount());

3. What did you expect to see?

class IndexHeader attribute indexCount as follows ：
private AtomicInteger indexCount = new AtomicInteger(0);

[Dovelol]

Why is the IndexHeader attribute indexCount initial value is 1 not 0？