What would be a good use-case scenario for the Spliterator in Java 8?

data-structures, iterator, java, java-8, spliterator

Solution

Normally, an application developer would not consume the `Spliterator` API directly. But if you are providing an API, and implement your own collection-like class, you can implement `Spliterator` to adapt your collection to the `Stream` API. This supports a functional approach, parallel processing, and other features.

For example, I wrote a utility to enumerate IP addresses in a network, specified by CIDR notation. It's not really a collection; that is, it doesn't carry list of all of the addresses in memory at once, only the network number and netmask. But by exposing a `Spliterator`, it can be easily adapted to a `Stream`. (Each `Spliterator` just tracks the current IP address and maximum address in its share of the network.)

Another example from the core Java runtime is `DirectoryStream` for traversing the file system.

Problem

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