Package org.apache.hadoop.ozone.om

Class ListIterator.MinHeapIterator

java.lang.Object
org.apache.hadoop.ozone.om.ListIterator.MinHeapIterator
All Implemented Interfaces:
Closeable, AutoCloseable, Iterator<ListIterator.HeapEntry>, ListIterator.ClosableIterator
Enclosing class:
ListIterator
public static class ListIterator.MinHeapIterator extends Object implements ListIterator.ClosableIterator
Implement lexicographical sorting of the file status by sorting file status across multiple lists. Each of these lists are sorted internally. This class implements sorted output by implementing a min heap based iterator where the initial element from each of sorted list is inserted. The least entry is removed and the next entry from the same list from which the entry is removed is added into the list. For example RawDir - a1, a3, a5, a7 RawFile - a2, a4, a6, a8 Min Heap is initially composed of {(a1, RawDir), (a2, RawFile)} The least element is removed i.e a1 and then next entry from RawDir is inserted into minheap resulting in {(a2, RawFile), (a3, RawDir)} This process is repeated till both the lists are exhausted.