Collectors toSet() in Java with Examples
Collectors toSet() returns a Collector that accumulates the input elements into a new Set. There are no guarantees on the type, mutability, serializability, or thread-safety of the Set returned. This is an unordered Collector i.e, the collection operation does not commit to preserving the encounter order of input elements.
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public static <T> Collector<T, ?, Set<T>> toSet()
- T: The type of the input elements.
- Interface Collector<T, A, R>: A mutable reduction operation that accumulates input elements into a mutable result container, optionally transforming the accumulated result into a final representation after all input elements have been processed. Reduction operations can be performed either sequentially or in parallel.
- T: The type of input elements to the reduction operation.
- A: The mutable accumulation type of the reduction operation.
- R: The result type of the reduction operation.
- Set: A collection that contains no duplicate elements. More formally, sets contain no pair of elements e1 and e2 such that e1.equals(e2), and at most one null element.
Return Value: A Collector which collects all the input elements into a Set.
Below are the examples to illustrate toSet() method:
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