Package com.landawn.abacus.util
Class u.Optional<T>
java.lang.Object
com.landawn.abacus.util.u.Optional<T>
- Type Parameters:
T
-
- All Implemented Interfaces:
Immutable
- Enclosing class:
u
The Class Optional.
-
Field Summary
Modifier and TypeFieldDescriptionstatic final u.Optional<Boolean>
PresentsBoolean.FALSE
.static final u.Optional<Boolean>
PresentsBoolean.TRUE
. -
Method Summary
Modifier and TypeMethodDescription__()
boolean
static <T> u.Optional<T>
empty()
boolean
<E extends Exception>
u.Optional<T>filter
(Throwables.Predicate<? super T, E> predicate) <U,
E extends Exception>
u.Optional<U>flatMap
(Throwables.Function<? super T, u.Optional<U>, E> mapper) static <T> u.Optional<T>
get()
int
hashCode()
<E extends Exception>
u.Optional<T>ifPresent
(Throwables.Consumer<? super T, E> action) <E extends Exception,
E2 extends Exception>
u.Optional<T>ifPresentOrElse
(Throwables.Consumer<? super T, E> action, Throwables.Runnable<E2> emptyAction) If present or else.boolean
isEmpty()
Checks if is empty.boolean
Checks if is present.<U,
E extends Exception>
u.Nullable<U>map
(Throwables.Function<? super T, ? extends U, E> mapper) <E extends Exception>
u.OptionalBooleanmapToBoolean
(Throwables.ToBooleanFunction<? super T, E> mapper) Map to boolean.<E extends Exception>
u.OptionalBytemapToByte
(Throwables.ToByteFunction<? super T, E> mapper) Map to byte.<E extends Exception>
u.OptionalCharmapToChar
(Throwables.ToCharFunction<? super T, E> mapper) Map to char.<E extends Exception>
u.OptionalDoublemapToDouble
(Throwables.ToDoubleFunction<? super T, E> mapper) Map to double.<E extends Exception>
u.OptionalFloatmapToFloat
(Throwables.ToFloatFunction<? super T, E> mapper) Map to float.<E extends Exception>
u.OptionalIntmapToInt
(Throwables.ToIntFunction<? super T, E> mapper) Map to int.<E extends Exception>
u.OptionalLongmapToLong
(Throwables.ToLongFunction<? super T, E> mapper) Map to long.<U,
E extends Exception>
u.Optional<U>mapToNonNull
(Throwables.Function<? super T, ? extends U, E> mapper) <E extends Exception>
u.OptionalShortmapToShort
(Throwables.ToShortFunction<? super T, E> mapper) Map to short.static u.Optional<String>
static <T> u.Optional<T>
of
(T value) static u.Optional<String>
ofNullable
(String value) static <T> u.Optional<T>
ofNullable
(T value) <E extends Exception>
u.Optional<T>or
(Throwables.Supplier<u.Optional<? extends T>, E> supplier) orElseGet
(Throwables.Supplier<? extends T, E> other) Or else get.Or else throw.orElseThrow
(Supplier<? extends X> exceptionSupplier) Or else throw.orNull()
Deprecated.stream()
To immutable list.To immutable set.toList()
toSet()
toString()
-
Field Details
-
TRUE
PresentsBoolean.TRUE
. -
FALSE
PresentsBoolean.FALSE
.
-
-
Method Details
-
empty
- Type Parameters:
T
-- Returns:
-
of
-
of
- Type Parameters:
T
-- Parameters:
value
-- Returns:
-
ofNullable
-
ofNullable
- Type Parameters:
T
-- Parameters:
value
-- Returns:
-
from
- Type Parameters:
T
-- Parameters:
op
-- Returns:
-
get
- Returns:
- Throws:
NoSuchElementException
- the no such element exception
-
isPresent
public boolean isPresent()Checks if is present.- Returns:
- true, if is present
-
isEmpty
public boolean isEmpty()Checks if is empty.- Returns:
- true, if is empty
-
ifPresent
public <E extends Exception> u.Optional<T> ifPresent(Throwables.Consumer<? super T, E> action) throws E- Type Parameters:
E
-- Parameters:
action
-- Returns:
- itself
- Throws:
E
- the e
-
ifPresentOrElse
public <E extends Exception,E2 extends Exception> u.Optional<T> ifPresentOrElse(Throwables.Consumer<? super T, E> action, Throwables.Runnable<E2> emptyAction) throws E, E2If present or else.- Type Parameters:
E
-E2
-- Parameters:
action
-emptyAction
-- Returns:
- itself
- Throws:
E
- the eE2
- the e2
-
filter
public <E extends Exception> u.Optional<T> filter(Throwables.Predicate<? super T, E> predicate) throws E- Type Parameters:
E
-- Parameters:
predicate
-- Returns:
- Throws:
E
- the e
-
map
public <U,E extends Exception> u.Nullable<U> map(Throwables.Function<? super T, ? extends U, throws EE> mapper) - Type Parameters:
U
-E
-- Parameters:
mapper
-- Returns:
- Throws:
E
- the e
-
mapToNonNull
public <U,E extends Exception> u.Optional<U> mapToNonNull(Throwables.Function<? super T, ? extends U, throws EE> mapper) - Type Parameters:
U
-E
-- Parameters:
mapper
-- Returns:
- Throws:
E
- the e
-
mapToBoolean
public <E extends Exception> u.OptionalBoolean mapToBoolean(Throwables.ToBooleanFunction<? super T, E> mapper) throws EMap to boolean.- Type Parameters:
E
-- Parameters:
mapper
-- Returns:
- Throws:
E
- the e
-
mapToChar
public <E extends Exception> u.OptionalChar mapToChar(Throwables.ToCharFunction<? super T, E> mapper) throws EMap to char.- Type Parameters:
E
-- Parameters:
mapper
-- Returns:
- Throws:
E
- the e
-
mapToByte
public <E extends Exception> u.OptionalByte mapToByte(Throwables.ToByteFunction<? super T, E> mapper) throws EMap to byte.- Type Parameters:
E
-- Parameters:
mapper
-- Returns:
- Throws:
E
- the e
-
mapToShort
public <E extends Exception> u.OptionalShort mapToShort(Throwables.ToShortFunction<? super T, E> mapper) throws EMap to short.- Type Parameters:
E
-- Parameters:
mapper
-- Returns:
- Throws:
E
- the e
-
mapToInt
public <E extends Exception> u.OptionalInt mapToInt(Throwables.ToIntFunction<? super T, E> mapper) throws EMap to int.- Type Parameters:
E
-- Parameters:
mapper
-- Returns:
- Throws:
E
- the e
-
mapToLong
public <E extends Exception> u.OptionalLong mapToLong(Throwables.ToLongFunction<? super T, E> mapper) throws EMap to long.- Type Parameters:
E
-- Parameters:
mapper
-- Returns:
- Throws:
E
- the e
-
mapToFloat
public <E extends Exception> u.OptionalFloat mapToFloat(Throwables.ToFloatFunction<? super T, E> mapper) throws EMap to float.- Type Parameters:
E
-- Parameters:
mapper
-- Returns:
- Throws:
E
- the e
-
mapToDouble
public <E extends Exception> u.OptionalDouble mapToDouble(Throwables.ToDoubleFunction<? super T, E> mapper) throws EMap to double.- Type Parameters:
E
-- Parameters:
mapper
-- Returns:
- Throws:
E
- the e
-
flatMap
public <U,E extends Exception> u.Optional<U> flatMap(Throwables.Function<? super T, u.Optional<U>, throws EE> mapper) - Type Parameters:
U
-E
-- Parameters:
mapper
-- Returns:
- Throws:
E
- the e
-
contains
-
or
public <E extends Exception> u.Optional<T> or(Throwables.Supplier<u.Optional<? extends T>, E> supplier) throws E- Type Parameters:
E
-- Parameters:
supplier
-- Returns:
- Throws:
E
- the e
-
orNull
Deprecated.usingorElseNull()
- Returns:
-
orElseNull
- Returns:
-
orElse
- Parameters:
other
-- Returns:
-
orElseGet
Or else get.- Type Parameters:
E
-- Parameters:
other
-- Returns:
- Throws:
E
- the e
-
orElseThrow
Or else throw.- Returns:
- Throws:
NoSuchElementException
- the no such element exception
-
orElseThrow
Or else throw.- Type Parameters:
X
-- Parameters:
exceptionSupplier
-- Returns:
- Throws:
X
- the x
-
stream
- Returns:
-
toList
- Returns:
-
toSet
- Returns:
-
toImmutableList
To immutable list.- Returns:
-
toImmutableSet
To immutable set.- Returns:
-
__
- Returns:
-
equals
-
hashCode
public int hashCode() -
toString
-
orElseNull()