| Package | Description | 
|---|---|
| java.time.temporal | 
 Access to date and time using fields and units, and date time adjusters. | 
| java.util | Contains the collections framework, legacy collection classes, event model,
date and time facilities, internationalization, and miscellaneous utility
classes (a string tokenizer, a random-number generator, and a bit array). | 
| java.util.concurrent | Utility classes commonly useful in concurrent programming. | 
| java.util.concurrent.atomic | A small toolkit of classes that support lock-free thread-safe
 programming on single variables. | 
| java.util.function | Functional interfaces provide target types for lambda expressions
 and method references. | 
| java.util.stream | Classes to support functional-style operations on streams of elements, such
 as map-reduce transformations on collections. | 
| Modifier and Type | Method and Description | 
|---|---|
| static TemporalAdjuster | TemporalAdjusters. ofDateAdjuster(UnaryOperator<LocalDate> dateBasedAdjuster)Obtains a  TemporalAdjusterthat wraps a date adjuster. | 
| Modifier and Type | Method and Description | 
|---|---|
| void | ArrayList. replaceAll(UnaryOperator<E> operator) | 
| void | Vector. replaceAll(UnaryOperator<E> operator) | 
| default void | List. replaceAll(UnaryOperator<E> operator)Replaces each element of this list with the result of applying the
 operator to that element. | 
| Modifier and Type | Method and Description | 
|---|---|
| void | CopyOnWriteArrayList. replaceAll(UnaryOperator<E> operator) | 
| Modifier and Type | Method and Description | 
|---|---|
| E | AtomicReferenceArray. getAndUpdate(int i,
            UnaryOperator<E> updateFunction)Atomically updates the element at index  iwith the results
 of applying the given function, returning the previous value. | 
| V | AtomicReferenceFieldUpdater. getAndUpdate(T obj,
            UnaryOperator<V> updateFunction)Atomically updates the field of the given object managed by this updater
 with the results of applying the given function, returning the previous
 value. | 
| V | AtomicReference. getAndUpdate(UnaryOperator<V> updateFunction)Atomically updates the current value with the results of
 applying the given function, returning the previous value. | 
| E | AtomicReferenceArray. updateAndGet(int i,
            UnaryOperator<E> updateFunction)Atomically updates the element at index  iwith the results
 of applying the given function, returning the updated value. | 
| V | AtomicReferenceFieldUpdater. updateAndGet(T obj,
            UnaryOperator<V> updateFunction)Atomically updates the field of the given object managed by this updater
 with the results of applying the given function, returning the updated
 value. | 
| V | AtomicReference. updateAndGet(UnaryOperator<V> updateFunction)Atomically updates the current value with the results of
 applying the given function, returning the updated value. | 
| Modifier and Type | Method and Description | 
|---|---|
| static <T> UnaryOperator<T> | UnaryOperator. identity()Returns a unary operator that always returns its input argument. | 
| Modifier and Type | Method and Description | 
|---|---|
| static <T> Stream<T> | Stream. iterate(T seed,
       UnaryOperator<T> f)Returns an infinite sequential ordered  Streamproduced by iterative
 application of a functionfto an initial elementseed,
 producing aStreamconsisting ofseed,f(seed),f(f(seed)), etc. | 
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