OptionalInt
public
final
class
OptionalInt
extends Object
| java.lang.Object | |
| ↳ | java.util.OptionalInt |
A container object which may or may not contain a int value.
If a value is present, isPresent() will return true and
getAsInt() will return the value.
Additional methods that depend on the presence or absence of a contained
value are provided, such as orElse()
(return a default value if value not present) and
ifPresent() (execute a block
of code if the value is present).
Summary
Public methods | |
|---|---|
static
OptionalInt
|
empty()
Returns an empty |
boolean
|
equals(Object obj)
Indicates whether some other object is "equal to" this OptionalInt. |
int
|
getAsInt()
If a value is present in this |
int
|
hashCode()
Returns the hash code value of the present value, if any, or 0 (zero) if no value is present. |
void
|
ifPresent(IntConsumer consumer)
Have the specified consumer accept the value if a value is present, otherwise do nothing. |
boolean
|
isPresent()
Return |
static
OptionalInt
|
of(int value)
Return an |
int
|
orElse(int other)
Return the value if present, otherwise return |
int
|
orElseGet(IntSupplier other)
Return the value if present, otherwise invoke |
<X extends Throwable>
int
|
orElseThrow(Supplier<X> exceptionSupplier)
Return the contained value, if present, otherwise throw an exception to be created by the provided supplier. |
String
|
toString()
Returns a string representation of the object. Returns a non-empty string representation of this object suitable for debugging. |
Inherited methods | |
|---|---|
java.lang.Object
| |
Public methods
empty
OptionalInt empty ()
Returns an empty OptionalInt instance. No value is present for this
OptionalInt.
API Note:
- Though it may be tempting to do so, avoid testing if an object
is empty by comparing with
==against instances returned byOption.empty(). There is no guarantee that it is a singleton. Instead, useisPresent().
| Returns | |
|---|---|
OptionalInt |
an empty OptionalInt
|
equals
boolean equals (Object obj)
Indicates whether some other object is "equal to" this OptionalInt. The other object is considered equal if:
- it is also an
OptionalIntand; - both instances have no value present or;
- the present values are "equal to" each other via
==.
| Parameters | |
|---|---|
obj |
Object:
an object to be tested for equality |
| Returns | |
|---|---|
boolean |
{code true} if the other object is "equal to" this object
otherwise false
|
getAsInt
int getAsInt ()
If a value is present in this OptionalInt, returns the value,
otherwise throws NoSuchElementException.
| Returns | |
|---|---|
int |
the value held by this OptionalInt |
| Throws | |
|---|---|
NoSuchElementException |
if there is no value present |
See also:
hashCode
int hashCode ()
Returns the hash code value of the present value, if any, or 0 (zero) if no value is present.
| Returns | |
|---|---|
int |
hash code value of the present value or 0 if no value is present |
ifPresent
void ifPresent (IntConsumer consumer)
Have the specified consumer accept the value if a value is present, otherwise do nothing.
| Parameters | |
|---|---|
consumer |
IntConsumer:
block to be executed if a value is present |
| Throws | |
|---|---|
NullPointerException |
if value is present and consumer is
null
|
isPresent
boolean isPresent ()
Return true if there is a value present, otherwise false.
| Returns | |
|---|---|
boolean |
true if there is a value present, otherwise false
|
of
OptionalInt of (int value)
Return an OptionalInt with the specified value present.
| Parameters | |
|---|---|
value |
int:
the value to be present |
| Returns | |
|---|---|
OptionalInt |
an OptionalInt with the value present
|
orElse
int orElse (int other)
Return the value if present, otherwise return other.
| Parameters | |
|---|---|
other |
int:
the value to be returned if there is no value present |
| Returns | |
|---|---|
int |
the value, if present, otherwise other
|
orElseGet
int orElseGet (IntSupplier other)
Return the value if present, otherwise invoke other and return
the result of that invocation.
| Parameters | |
|---|---|
other |
IntSupplier:
a IntSupplier whose result is returned if no value
is present |
| Returns | |
|---|---|
int |
the value if present otherwise the result of other.getAsInt() |
| Throws | |
|---|---|
NullPointerException |
if value is not present and other is
null
|
orElseThrow
int orElseThrow (Supplier<X> exceptionSupplier)
Return the contained value, if present, otherwise throw an exception to be created by the provided supplier.
API Note:
- A method reference to the exception constructor with an empty
argument list can be used as the supplier. For example,
IllegalStateException::new
| Parameters | |
|---|---|
exceptionSupplier |
Supplier:
The supplier which will return the exception to
be thrown |
| Returns | |
|---|---|
int |
the present value |
| Throws | |
|---|---|
|
if there is no value present |
NullPointerException |
if no value is present and
exceptionSupplier is null
|
Throwable |
|
toString
String toString ()
Returns a string representation of the object. In general, the
toString method returns a string that
"textually represents" this object. The result should
be a concise but informative representation that is easy for a
person to read.
It is recommended that all subclasses override this method.
The toString method for class Object
returns a string consisting of the name of the class of which the
object is an instance, the at-sign character `@', and
the unsigned hexadecimal representation of the hash code of the
object. In other words, this method returns a string equal to the
value of:
Returns a non-empty string representation of this object suitable for debugging. The exact presentation format is unspecified and may vary between implementations and versions.getClass().getName() + '@' + Integer.toHexString(hashCode())
Implementation Requirements:
- If a value is present the result must include its string representation in the result. Empty and present instances must be unambiguously differentiable.
| Returns | |
|---|---|
String |
the string representation of this instance |
Interfaces
- Collection
- Comparator
- Deque
- Enumeration
- EventListener
- Formattable
- Iterator
- List
- ListIterator
- Map
- Map.Entry
- NavigableMap
- NavigableSet
- Observer
- PrimitiveIterator
- PrimitiveIterator.OfDouble
- PrimitiveIterator.OfInt
- PrimitiveIterator.OfLong
- Queue
- RandomAccess
- Set
- SortedMap
- SortedSet
- Spliterator
- Spliterator.OfDouble
- Spliterator.OfInt
- Spliterator.OfLong
- Spliterator.OfPrimitive
Classes
- AbstractCollection
- AbstractList
- AbstractMap
- AbstractMap.SimpleEntry
- AbstractMap.SimpleImmutableEntry
- AbstractQueue
- AbstractSequentialList
- AbstractSet
- ArrayDeque
- ArrayList
- Arrays
- BitSet
- Calendar
- Collections
- Currency
- Date
- Dictionary
- DoubleSummaryStatistics
- EnumMap
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- EventListenerProxy
- EventObject
- FormattableFlags
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- Hashtable
- IdentityHashMap
- IntSummaryStatistics
- LinkedHashMap
- LinkedHashSet
- LinkedList
- ListResourceBundle
- Locale
- Locale.Builder
- LongSummaryStatistics
- Objects
- Observable
- Optional
- OptionalDouble
- OptionalInt
- OptionalLong
- PriorityQueue
- Properties
- PropertyPermission
- PropertyResourceBundle
- Random
- ResourceBundle
- ResourceBundle.Control
- Scanner
- ServiceLoader
- SimpleTimeZone
- Spliterators
- Spliterators.AbstractDoubleSpliterator
- Spliterators.AbstractIntSpliterator
- Spliterators.AbstractLongSpliterator
- Spliterators.AbstractSpliterator
- SplittableRandom
- Stack
- StringJoiner
- StringTokenizer
- Timer
- TimerTask
- TimeZone
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Enums
Exceptions
- ConcurrentModificationException
- DuplicateFormatFlagsException
- EmptyStackException
- FormatFlagsConversionMismatchException
- FormatterClosedException
- IllegalFormatCodePointException
- IllegalFormatConversionException
- IllegalFormatException
- IllegalFormatFlagsException
- IllegalFormatPrecisionException
- IllegalFormatWidthException
- IllformedLocaleException
- InputMismatchException
- InvalidPropertiesFormatException
- MissingFormatArgumentException
- MissingFormatWidthException
- MissingResourceException
- NoSuchElementException
- TooManyListenersException
- UnknownFormatConversionException
- UnknownFormatFlagsException
Errors

