Represents something than can be CoGrouped with another CoGroupable
Closures are difficult for serialization.
This encodes the rules that 1) sorting is only possible before doing any reduce, 2) reversing is only possible after sorting.
used for types that may know how many reducers they need e.
If we can HashJoin, then we can CoGroup, but not vice-versa i.
Only intended to be use to implement the hashCogroup on TypedPipe/Grouped
You should use a view here If you avoid toPipe, this class is more efficient than IterableSource.
This is for the case where you don't want to expose any structure but the ability to operate on an iterator of the values
Represents sharded lists of items of type T There are exactly two the fundamental operations: toTypedPipe: marks the end of the grouped-on-key operations.
Represents anything that starts as a TypedPipe of Key Value, where the value type has been erased.
This is a class that models the logical portion of the reduce step.
After sorting, we are no longer CoGroupable, and we can only call reverse in the initial SortedGrouped created from the Sortable: .
Think of a TypedPipe as a distributed unordered list that may or may not yet have been materialized in memory or disk.
This is an instance of a TypedPipe that wraps a cascading Pipe
Opposite of TypedSource, used for writing into
This is the state after we have done some reducing.
ValuePipe is special case of a TypedPipe of just a optional single element.
used for objects that may _set_ how many reducers they need e.
lookupJoin simulates the behavior of a realtime system attempting to leftJoin (K, V) pairs against some other value type (JoinedV) by performing realtime lookups on a key-value Store.
implicits for the type-safe DSL import TDsl.
factory methods for TypedPipe, which is the typed representation of distributed lists in scalding.