public static class Maybe.Nothing<T> extends java.lang.Object implements Maybe<T>
Maybe.µ, Maybe.CompletableMaybe<ORG,T2>, Maybe.Instances, Maybe.Just<T>, Maybe.Lazy<T>, Maybe.Nothing<T>
Value.ValueImpl<T>
Convertable.SupplierToConvertable<T>
Fn0.FunctionalOperations<R>, Fn0.SupplierKind<R>
Constructor and Description |
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Nothing() |
Modifier and Type | Method and Description |
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boolean |
equals(java.lang.Object obj) |
Maybe<T> |
filter(java.util.function.Predicate<? super T> test)
Keep only elements for which the supplied predicates hold
e.g.
|
<R> Maybe<R> |
flatMap(java.util.function.Function<? super T,? extends MonadicValue<? extends R>> mapper)
A flattening transformation operation (@see
Optional.flatMap(Function) |
<R> Maybe.Nothing<R> |
flatMapI(java.util.function.Function<? super T,? extends java.lang.Iterable<? extends R>> mapper)
A flattening transformation operation that takes the first value from the returned Iterable.
|
<R> Maybe.Nothing<R> |
flatMapP(java.util.function.Function<? super T,? extends org.reactivestreams.Publisher<? extends R>> mapper)
A flattening transformation operation that takes the first value from the returned Publisher.
|
void |
forEach(java.util.function.Consumer<? super T> action) |
T |
get()
Apply this function to the arguments.
|
boolean |
isPresent() |
<R> Maybe<R> |
map(java.util.function.Function<? super T,? extends R> mapper)
Transform this functor using the supplied transformation function
|
T |
orElse(T value)
Get the contained value or else the provided alternative
|
T |
orElseGet(java.util.function.Supplier<? extends T> value)
An equivalent operation to
Optional.orElseGet(Supplier)
Returns a value generated by the provided Supplier if this Convertable is empty or
contains a null value. |
Maybe<T> |
recover(java.util.function.Supplier<T> value) |
Maybe<T> |
recover(T value) |
Maybe<T> |
recoverWith(java.util.function.Supplier<? extends Maybe<T>> fn) |
java.util.Optional<T> |
toOptional() |
java.lang.String |
toString() |
<R> R |
visit(java.util.function.Function<? super T,? extends R> some,
java.util.function.Supplier<? extends R> none)
The provided function is executed with the value stored in this Visitable if one is present,
otherwise the provided Supplier is executed instead.
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clone, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
accumulateJust, accumulateJust, accumulateJust, anyM, arrow, cast, coflatMap, combine, combineEager, filterNot, flatMapS, forEach2, forEach2, forEach3, forEach3, forEach4, forEach4, fromEval, fromEvalNullable, fromEvalOf, fromEvalOptional, fromFuture, fromIterable, fromLazy, fromOptional, fromOptional, fromOptionalKind, fromPublisher, fromStream, just, liftM, maybe, narrow, narrowK, narrowOptional, nest, none, notNull, of, ofNullable, ofType, peek, retry, retry, sequence, sequence, sequenceJust, toMaybe, trampoline, unit, widen2, zip, zip, zip, zip3, zip3, zip4, zip4, zipP, zipP, zipS, zipS, zipWith, zipWithP, zipWithS
apply, generate, iterate, iterator, mkString, newSubscriber, stream, subscribe, test, toEvalAlways, toEvalLater, toEvalNow, toIor, toTry, toTry, toTry, toXor, toXor
endsWith, endsWithIterable, findAny, findFirst, firstValue, foldLeft, foldLeft, foldLeft, foldLeft, foldRight, foldRight, foldRight, foldRightMapToType, get, groupBy, join, join, join, mapReduce, mapReduce, print, print, printErr, printOut, reduce, reduce, reduce, reduce, reduce, reduce, reduce, schedule, scheduleFixedDelay, scheduleFixedRate, single, single, singleOptional, startsWith, startsWithIterable, toConcurrentLazyCollection, toConcurrentLazyStreamable, toLazyCollection, xMatch
futureStream, getStreamable, isEmpty, jdkStream, reactiveSeq, reveresedJDKStream, reveresedStream
collect, fromSupplier, orElseThrow, toCompletableFuture, toCompletableFutureAsync, toCompletableFutureAsync, toFuture, toFutureWAsync, toFutureWAsync, toStream
public <R> Maybe<R> map(java.util.function.Function<? super T,? extends R> mapper)
Transformable
of(1,2,3).map(i->i*2)
//[2,4,6]
map
in interface MonadicValue<T>
map
in interface Transformable<T>
map
in interface Maybe<T>
mapper
- Transformation functionpublic <R> Maybe<R> flatMap(java.util.function.Function<? super T,? extends MonadicValue<? extends R>> mapper)
MonadicValue
Optional.flatMap(Function)
Eval.now(1).map(i->i+2).flatMap(i->Eval.later(()->i*3);
//Eval[9]
public Maybe<T> filter(java.util.function.Predicate<? super T> test)
Filters
of(1,2,3).filter(i->i>2);
//[3]
public T get()
org.jooq.lambda.function.Function0
get
in interface Convertable<T>
get
in interface java.util.function.Supplier<T>
get
in interface org.jooq.lambda.function.Function0<T>
public Maybe<T> recoverWith(java.util.function.Supplier<? extends Maybe<T>> fn)
recoverWith
in interface Maybe<T>
public <R> R visit(java.util.function.Function<? super T,? extends R> some, java.util.function.Supplier<? extends R> none)
Visitable
visit
in interface Convertable<T>
visit
in interface Visitable<T>
visit
in interface Maybe<T>
some
- Function to execute if this Visitable has a valuenone
- Supplier to execute if this Visitable does not have a Valuepublic java.util.Optional<T> toOptional()
toOptional
in interface Convertable<T>
public java.lang.String toString()
toString
in class java.lang.Object
public boolean isPresent()
public boolean equals(java.lang.Object obj)
equals
in class java.lang.Object
public T orElse(T value)
Convertable
orElse
in interface Convertable<T>
public T orElseGet(java.util.function.Supplier<? extends T> value)
Convertable
Optional.orElseGet(Supplier)
Returns a value generated by the provided Supplier if this Convertable is empty or
contains a null value.orElseGet
in interface Convertable<T>
value
- Supplier to generate value if this convertable is emptypublic <R> Maybe.Nothing<R> flatMapI(java.util.function.Function<? super T,? extends java.lang.Iterable<? extends R>> mapper)
MonadicValue
Maybe.just(1).map(i->i+2).flatMapI(i->Arrays.asList(()->i*3,20);
//Maybe[9]
public <R> Maybe.Nothing<R> flatMapP(java.util.function.Function<? super T,? extends org.reactivestreams.Publisher<? extends R>> mapper)
MonadicValue
FutureW.ofResult(1).map(i->i+2).flatMapP(i->Flux.just(()->i*3,20);
//FutureW[9]