## Uses of Interface
java.util.concurrent.ConcurrentMap

Packages that use ConcurrentMap
java.net.http: HTTP Client and WebSocket APIs
java.util.concurrent: Utility classes commonly useful in concurrent programming.
java.util.stream: Classes to support functional-style operations on streams of elements, such as map-reduce transformations on collections.

### Uses of ConcurrentMap in java.net.http

Methods in java.net.http with parameters of type ConcurrentMap
`static <T> HttpResponse.PushPromiseHandler<T>` HttpResponse.PushPromiseHandler.`of​(Function<HttpRequest,​HttpResponse.BodyHandler<T>> pushPromiseHandler, ConcurrentMap<HttpRequest,​CompletableFuture<HttpResponse<T>>> pushPromisesMap)` Returns a push promise handler that accumulates push promises, and their responses, into the given map.

### Uses of ConcurrentMap in java.util.concurrent

Subinterfaces of ConcurrentMap in java.util.concurrent
`interface` `ConcurrentNavigableMap<K,​V>` A `ConcurrentMap` supporting `NavigableMap` operations, and recursively so for its navigable sub-maps.

Classes in java.util.concurrent that implement ConcurrentMap
`class` `ConcurrentHashMap<K,​V>` A hash table supporting full concurrency of retrievals and high expected concurrency for updates.
`class` `ConcurrentSkipListMap<K,​V>` A scalable concurrent `ConcurrentNavigableMap` implementation.

### Uses of ConcurrentMap in java.util.stream

Methods in java.util.stream with type parameters of type ConcurrentMap

`static <T,​K,​A,​D,​M extends ConcurrentMap<K,​D>>
Collector<T,​?,​M>`

Collectors.`groupingByConcurrent​(Function<? super T,​? extends K> classifier, Supplier<M> mapFactory, Collector<? super T,​A,​D> downstream)`

Returns a concurrent `Collector` implementing a cascaded "group by" operation on input elements of type `T`, grouping elements according to a classification function, and then performing a reduction operation on the values associated with a given key using the specified downstream `Collector`.

`static <T,​K,​U,​M extends ConcurrentMap<K,​U>>
Collector<T,​?,​M>`

Collectors.`toConcurrentMap​(Function<? super T,​? extends K> keyMapper, Function<? super T,​? extends U> valueMapper, BinaryOperator<U> mergeFunction, Supplier<M> mapFactory)`

Returns a concurrent `Collector` that accumulates elements into a `ConcurrentMap` whose keys and values are the result of applying the provided mapping functions to the input elements.

Methods in java.util.stream that return types with arguments of type ConcurrentMap
`static <T,​K> Collector<T,​?,​ConcurrentMap<K,​List<T>>>` Collectors.`groupingByConcurrent​(Function<? super T,​? extends K> classifier)` Returns a concurrent `Collector` implementing a "group by" operation on input elements of type `T`, grouping elements according to a classification function.

`static <T,​K,​A,​D>
Collector<T,​?,​ConcurrentMap<K,​D>>`

Collectors.`groupingByConcurrent​(Function<? super T,​? extends K> classifier, Collector<? super T,​A,​D> downstream)`

Returns a concurrent `Collector` implementing a cascaded "group by" operation on input elements of type `T`, grouping elements according to a classification function, and then performing a reduction operation on the values associated with a given key using the specified downstream `Collector`.

`static <T,​K,​U> Collector<T,​?,​ConcurrentMap<K,​U>>` Collectors.`toConcurrentMap​(Function<? super T,​? extends K> keyMapper, Function<? super T,​? extends U> valueMapper)` Returns a concurrent `Collector` that accumulates elements into a `ConcurrentMap` whose keys and values are the result of applying the provided mapping functions to the input elements.
`static <T,​K,​U> Collector<T,​?,​ConcurrentMap<K,​U>>` Collectors.`toConcurrentMap​(Function<? super T,​? extends K> keyMapper, Function<? super T,​? extends U> valueMapper, BinaryOperator<U> mergeFunction)` Returns a concurrent `Collector` that accumulates elements into a `ConcurrentMap` whose keys and values are the result of applying the provided mapping functions to the input elements.