Type Members

1.  class BitSet extends Serializable

   BitSet

   BitSet

   copy from spark

   A simple, fixed-size bit set implementation. This implementation is fast because it avoids safety/bound checking.

   Version

   1.0

   Since

   2021/3/30 3:35 下午

2.  class OpenHashMap[K, V] extends Iterable[(K, V)] with Serializable

   OpenHashMap

   OpenHashMap

   A fast hash map implementation for nullable keys. This hash map supports insertions and updates, but not deletions. This map is about 5X faster than java.util.HashMap, while using much less space overhead.

   Under the hood, it uses our OpenHashSet implementation.

   NOTE: when using numeric type as the value type, the user of this class should be careful to distinguish between the 0/0.0/0L and non-exist value

   Version

   1.0

   Since

   2021/3/30 5:29 下午

3.  class OpenHashSet[T] extends Serializable

   A simple, fast hash set optimized for non-null insertion-only use case, where keys are never removed.

   A simple, fast hash set optimized for non-null insertion-only use case, where keys are never removed.

   The underlying implementation uses Scala compiler's specialization to generate optimized storage for four primitive types (Long, Int, Double, and Float). It is much faster than Java's standard HashSet while incurring much less memory overhead. This can serve as building blocks for higher level data structures such as an optimized HashMap.

   This OpenHashSet is designed to serve as building blocks for higher level data structures such as an optimized hash map. Compared with standard hash set implementations, this class provides its various callbacks interfaces (e.g. allocateFunc, moveFunc) and interfaces to retrieve the position of a key in the underlying array.

   It uses quadratic probing with a power-of-2 hash table size, which is guaranteed to explore all spaces for each key (see http://en.wikipedia.org/wiki/Quadratic_probing).