com.landawn.abacus.util

Class u.Nullable<T>

java.lang.Object

com.landawn.abacus.util.u.Nullable<T>

Type Parameters:

T -

All Implemented Interfaces:

Immutable

Enclosing class:

u

@Immutable
public static final class u.Nullable<T>
extends Object
implements Immutable

The Class Nullable.

Field Summary

Fields

Modifier and Type	Field and Description
static u.Nullable<Boolean>	FALSE Presents Boolean.FALSE.
static u.Nullable<Boolean>	TRUE Presents Boolean.TRUE.

Method Summary

Modifier and Type	Method and Description
boolean	contains(T element)
static <T> u.Nullable<T>	empty()
boolean	equals(Object obj)
<E extends Exception> u.Nullable<T>	filter(Throwables.Predicate<? super T,E> predicate)
<E extends Exception> u.Optional<T>	filterIfNotNull(Throwables.Predicate<? super T,E> predicate) Filter if not null.
<U,E extends Exception> u.Nullable<U>	flatMap(Throwables.Function<? super T,u.Nullable<U>,E> mapper)
<U,E extends Exception> u.Nullable<U>	flatMapIfNotNull(Throwables.Function<? super T,u.Nullable<U>,E> mapper) Flat map if not null.
static <T> u.Nullable<T>	from(u.Optional<T> optional)
T	get()
int	hashCode()
<E extends Exception> u.Nullable<T>	ifNotNull(Throwables.Consumer<? super T,E> action) If not null.
<E extends Exception,E2 extends Exception> u.Nullable<T>	ifNotNullOrElse(Throwables.Consumer<? super T,E> action, Throwables.Runnable<E2> emptyAction) If not null or else.
<E extends Exception> u.Nullable<T>	ifPresent(Throwables.Consumer<? super T,E> action)
<E extends Exception,E2 extends Exception> u.Nullable<T>	ifPresentOrElse(Throwables.Consumer<? super T,E> action, Throwables.Runnable<E2> emptyAction) If present or else.
boolean	isEmpty() Deprecated. replaced by isNotPresent()
boolean	isNotNull() Returns true if the value is present and it's not null, otherwise returns false.
boolean	isNotPresent() Returns true if the value is not present, otherwise returns false.
boolean	isNull() Returns true if the value is not present, or it is present but it's null, otherwise returns false.
boolean	isPresent() Returns true if the value is present, otherwise returns false.
<U,E extends Exception> u.Nullable<U>	map(Throwables.Function<? super T,? extends U,E> mapper)
<U,E extends Exception> u.Nullable<U>	mapIfNotNull(Throwables.Function<? super T,? extends U,E> mapper) Map if not null.
<E extends Exception> u.OptionalBoolean	mapToBoolean(Throwables.ToBooleanFunction<? super T,E> mapper) Map to boolean.
<E extends Exception> u.OptionalBoolean	mapToBooleanIfNotNull(Throwables.ToBooleanFunction<? super T,E> mapper) Map to boolean if not null.
<E extends Exception> u.OptionalByte	mapToByte(Throwables.ToByteFunction<? super T,E> mapper) Map to byte.
<E extends Exception> u.OptionalByte	mapToByteIfNotNull(Throwables.ToByteFunction<? super T,E> mapper) Map to byte if not null.
<E extends Exception> u.OptionalChar	mapToChar(Throwables.ToCharFunction<? super T,E> mapper) Map to char.
<E extends Exception> u.OptionalChar	mapToCharIfNotNull(Throwables.ToCharFunction<? super T,E> mapper) Map to char if not null.
<E extends Exception> u.OptionalDouble	mapToDouble(Throwables.ToDoubleFunction<? super T,E> mapper) Map to double.
<E extends Exception> u.OptionalDouble	mapToDoubleIfNotNull(Throwables.ToDoubleFunction<? super T,E> mapper) Map to double if not null.
<E extends Exception> u.OptionalFloat	mapToFloat(Throwables.ToFloatFunction<? super T,E> mapper) Map to float.
<E extends Exception> u.OptionalFloat	mapToFloatIfNotNull(Throwables.ToFloatFunction<? super T,E> mapper) Map to float if not null.
<E extends Exception> u.OptionalInt	mapToInt(Throwables.ToIntFunction<? super T,E> mapper) Map to int.
<E extends Exception> u.OptionalInt	mapToIntIfNotNull(Throwables.ToIntFunction<? super T,E> mapper) Map to int if not null.
<E extends Exception> u.OptionalLong	mapToLong(Throwables.ToLongFunction<? super T,E> mapper) Map to long.
<E extends Exception> u.OptionalLong	mapToLongIfNotNull(Throwables.ToLongFunction<? super T,E> mapper) Map to long if not null.
<U,E extends Exception> u.Optional<U>	mapToNonNull(Throwables.Function<? super T,? extends U,E> mapper)
<U,E extends Exception> u.Optional<U>	mapToNonNullIfNotNull(Throwables.Function<? super T,? extends U,E> mapper) Map if not null.
<E extends Exception> u.OptionalShort	mapToShort(Throwables.ToShortFunction<? super T,E> mapper) Map to short.
<E extends Exception> u.OptionalShort	mapToShortIfNotNull(Throwables.ToShortFunction<? super T,E> mapper) Map to short if not null.
static u.Nullable<String>	of(String value)
static <T> u.Nullable<T>	of(T value)
<E extends Exception> u.Nullable<T>	or(Throwables.Supplier<u.Nullable<? extends T>,E> supplier)
T	orElse(T other)
<E extends Exception> T	orElseGet(Throwables.Supplier<? extends T,E> other) Or else get.
<E extends Exception> T	orElseGetIfNull(Throwables.Supplier<? extends T,E> other) Or else get if null.
T	orElseIfNull(T other) Or else if null.
T	orElseThrow() Or else throw.
<X extends Throwable> T	orElseThrow(Supplier<? extends X> exceptionSupplier) Or else throw.
T	orElseThrowIfNull() Or else throw if null.
<X extends Throwable> T	orElseThrowIfNull(Supplier<? extends X> exceptionSupplier) Or else throw if null.
<E extends Exception> u.Nullable<T>	orIfNull(Throwables.Supplier<u.Nullable<? extends T>,E> supplier) Or if null.
T	orNull()
ImmutableList<T>	toImmutableList() To immutable list.
ImmutableList<T>	toImmutableListIfNotNull() To immutable list if not null.
ImmutableSet<T>	toImmutableSet() To immutable set.
ImmutableSet<T>	toImmutableSetIfNotNull() To immutable set if not null.
List<T>	toList()
List<T>	toListIfNotNull() To list if not null.
u.Optional<T>	toOptional()
Set<T>	toSet()
Set<T>	toSetIfNotNull() To set if not null.
String	toString()

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Field Detail

TRUE

public static final u.Nullable<Boolean> TRUE

Presents Boolean.TRUE.

FALSE

public static final u.Nullable<Boolean> FALSE

Presents Boolean.FALSE.

Method Detail

empty

public static <T> u.Nullable<T> empty()

Type Parameters:

T -

Returns:

of

public static u.Nullable<String> of(String value)

of

public static <T> u.Nullable<T> of(T value)

Type Parameters:

T -

Parameters:

value -

Returns:

from

public static <T> u.Nullable<T> from(u.Optional<T> optional)

Type Parameters:

T -

Parameters:

optional -

Returns:

get

public T get()
      throws NoSuchElementException

Returns:

Throws:

NoSuchElementException - the no such element exception

isPresent

public boolean isPresent()

Returns true if the value is present, otherwise returns false.

Returns:

true, if is present

isNotPresent

public boolean isNotPresent()

Returns true if the value is not present, otherwise returns false.

Returns:

true, if is not present

isEmpty

@Deprecated
public boolean isEmpty()

Deprecated. replaced by isNotPresent()

Returns true if the value is not present, otherwise returns false.

Returns:

true, if is empty

isNull

public boolean isNull()

Returns true if the value is not present, or it is present but it's null, otherwise returns false.

Returns:

true, if is null

isNotNull

public boolean isNotNull()

Returns true if the value is present and it's not null, otherwise returns false.

Returns:

true, if is not null

ifPresent

public <E extends Exception> u.Nullable<T> ifPresent(Throwables.Consumer<? super T,E> action)
                                              throws E extends Exception

Type Parameters:

E -

Parameters:

action -

Returns:

itself

Throws:

E - the e

E extends Exception

ifPresentOrElse

public <E extends Exception,E2 extends Exception> u.Nullable<T> ifPresentOrElse(Throwables.Consumer<? super T,E> action,
                                                                                Throwables.Runnable<E2> emptyAction)
                                                                         throws E extends Exception,
                                                                                E2 extends Exception

If present or else.

Type Parameters:

E -

E2 -

Parameters:

action -

emptyAction -

Returns:

itself

Throws:

E - the e

E2 - the e2

E extends Exception

ifNotNull

public <E extends Exception> u.Nullable<T> ifNotNull(Throwables.Consumer<? super T,E> action)
                                              throws E extends Exception

If not null.

Type Parameters:

E -

Parameters:

action -

Returns:

itself

Throws:

E - the e

E extends Exception

ifNotNullOrElse

public <E extends Exception,E2 extends Exception> u.Nullable<T> ifNotNullOrElse(Throwables.Consumer<? super T,E> action,
                                                                                Throwables.Runnable<E2> emptyAction)
                                                                         throws E extends Exception,
                                                                                E2 extends Exception

If not null or else.

Type Parameters:

E -

E2 -

Parameters:

action -

emptyAction -

Returns:

itself

Throws:

E - the e

E2 - the e2

E extends Exception

filter

public <E extends Exception> u.Nullable<T> filter(Throwables.Predicate<? super T,E> predicate)
                                           throws E extends Exception

Type Parameters:

E -

Parameters:

predicate -

Returns:

Throws:

E - the e

E extends Exception

filterIfNotNull

public <E extends Exception> u.Optional<T> filterIfNotNull(Throwables.Predicate<? super T,E> predicate)
                                                    throws E extends Exception

Filter if not null.

Type Parameters:

E -

Parameters:

predicate -

Returns:

Throws:

E - the e

E extends Exception

map

public <U,E extends Exception> u.Nullable<U> map(Throwables.Function<? super T,? extends U,E> mapper)
                                          throws E extends Exception

Type Parameters:

U -

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToNonNull

public <U,E extends Exception> u.Optional<U> mapToNonNull(Throwables.Function<? super T,? extends U,E> mapper)
                                                   throws E extends Exception

Type Parameters:

U -

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToBoolean

public <E extends Exception> u.OptionalBoolean mapToBoolean(Throwables.ToBooleanFunction<? super T,E> mapper)
                                                     throws E extends Exception

Map to boolean.

Type Parameters:

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToChar

public <E extends Exception> u.OptionalChar mapToChar(Throwables.ToCharFunction<? super T,E> mapper)
                                               throws E extends Exception

Map to char.

Type Parameters:

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToByte

public <E extends Exception> u.OptionalByte mapToByte(Throwables.ToByteFunction<? super T,E> mapper)
                                               throws E extends Exception

Map to byte.

Type Parameters:

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToShort

public <E extends Exception> u.OptionalShort mapToShort(Throwables.ToShortFunction<? super T,E> mapper)
                                                 throws E extends Exception

Map to short.

Type Parameters:

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToInt

public <E extends Exception> u.OptionalInt mapToInt(Throwables.ToIntFunction<? super T,E> mapper)
                                             throws E extends Exception

Map to int.

Type Parameters:

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToLong

public <E extends Exception> u.OptionalLong mapToLong(Throwables.ToLongFunction<? super T,E> mapper)
                                               throws E extends Exception

Map to long.

Type Parameters:

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToFloat

public <E extends Exception> u.OptionalFloat mapToFloat(Throwables.ToFloatFunction<? super T,E> mapper)
                                                 throws E extends Exception

Map to float.

Type Parameters:

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToDouble

public <E extends Exception> u.OptionalDouble mapToDouble(Throwables.ToDoubleFunction<? super T,E> mapper)
                                                   throws E extends Exception

Map to double.

Type Parameters:

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapIfNotNull

public <U,E extends Exception> u.Nullable<U> mapIfNotNull(Throwables.Function<? super T,? extends U,E> mapper)
                                                   throws E extends Exception

Map if not null.

Type Parameters:

U -

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToNonNullIfNotNull

public <U,E extends Exception> u.Optional<U> mapToNonNullIfNotNull(Throwables.Function<? super T,? extends U,E> mapper)
                                                            throws E extends Exception

Map if not null.

Type Parameters:

U -

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToBooleanIfNotNull

public <E extends Exception> u.OptionalBoolean mapToBooleanIfNotNull(Throwables.ToBooleanFunction<? super T,E> mapper)
                                                              throws E extends Exception

Map to boolean if not null.

Type Parameters:

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToCharIfNotNull

public <E extends Exception> u.OptionalChar mapToCharIfNotNull(Throwables.ToCharFunction<? super T,E> mapper)
                                                        throws E extends Exception

Map to char if not null.

Type Parameters:

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToByteIfNotNull

public <E extends Exception> u.OptionalByte mapToByteIfNotNull(Throwables.ToByteFunction<? super T,E> mapper)
                                                        throws E extends Exception

Map to byte if not null.

Type Parameters:

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToShortIfNotNull

public <E extends Exception> u.OptionalShort mapToShortIfNotNull(Throwables.ToShortFunction<? super T,E> mapper)
                                                          throws E extends Exception

Map to short if not null.

Type Parameters:

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToIntIfNotNull

public <E extends Exception> u.OptionalInt mapToIntIfNotNull(Throwables.ToIntFunction<? super T,E> mapper)
                                                      throws E extends Exception

Map to int if not null.

Type Parameters:

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToLongIfNotNull

public <E extends Exception> u.OptionalLong mapToLongIfNotNull(Throwables.ToLongFunction<? super T,E> mapper)
                                                        throws E extends Exception

Map to long if not null.

Type Parameters:

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToFloatIfNotNull

public <E extends Exception> u.OptionalFloat mapToFloatIfNotNull(Throwables.ToFloatFunction<? super T,E> mapper)
                                                          throws E extends Exception

Map to float if not null.

Type Parameters:

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

mapToDoubleIfNotNull

public <E extends Exception> u.OptionalDouble mapToDoubleIfNotNull(Throwables.ToDoubleFunction<? super T,E> mapper)
                                                            throws E extends Exception

Map to double if not null.

Type Parameters:

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

flatMap

public <U,E extends Exception> u.Nullable<U> flatMap(Throwables.Function<? super T,u.Nullable<U>,E> mapper)
                                              throws E extends Exception

Type Parameters:

U -

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

flatMapIfNotNull

public <U,E extends Exception> u.Nullable<U> flatMapIfNotNull(Throwables.Function<? super T,u.Nullable<U>,E> mapper)
                                                       throws E extends Exception

Flat map if not null.

Type Parameters:

U -

E -

Parameters:

mapper -

Returns:

Throws:

E - the e

E extends Exception

contains

public boolean contains(T element)

or

public <E extends Exception> u.Nullable<T> or(Throwables.Supplier<u.Nullable<? extends T>,E> supplier)
                                       throws E extends Exception

Type Parameters:

E -

Parameters:

supplier -

Returns:

Throws:

E - the e

E extends Exception

orIfNull

public <E extends Exception> u.Nullable<T> orIfNull(Throwables.Supplier<u.Nullable<? extends T>,E> supplier)
                                             throws E extends Exception

Or if null.

Type Parameters:

E -

Parameters:

supplier -

Returns:

Throws:

E - the e

E extends Exception

orNull

public T orNull()

Returns:

orElse

public T orElse(T other)

Parameters:

other -

Returns:

orElseGet

public <E extends Exception> T orElseGet(Throwables.Supplier<? extends T,E> other)
                                  throws E extends Exception

Or else get.

Type Parameters:

E -

Parameters:

other -

Returns:

Throws:

E - the e

E extends Exception

orElseThrow

public T orElseThrow()
              throws NoSuchElementException

Or else throw.

Returns:

Throws:

NoSuchElementException - the no such element exception

orElseThrow

public <X extends Throwable> T orElseThrow(Supplier<? extends X> exceptionSupplier)
                                    throws X extends Throwable

Or else throw.

Type Parameters:

X -

Parameters:

exceptionSupplier -

Returns:

Throws:

X - the x

X extends Throwable

orElseIfNull

public T orElseIfNull(T other)

Or else if null.

Parameters:

other -

Returns:

orElseGetIfNull

public <E extends Exception> T orElseGetIfNull(Throwables.Supplier<? extends T,E> other)
                                        throws E extends Exception

Or else get if null.

Type Parameters:

E -

Parameters:

other -

Returns:

Throws:

E - the e

E extends Exception

orElseThrowIfNull

public T orElseThrowIfNull()
                    throws NoSuchElementException

Or else throw if null.

Returns:

Throws:

NoSuchElementException - the no such element exception

orElseThrowIfNull

public <X extends Throwable> T orElseThrowIfNull(Supplier<? extends X> exceptionSupplier)
                                          throws X extends Throwable

Or else throw if null.

Type Parameters:

X -

Parameters:

exceptionSupplier -

Returns:

Throws:

X - the x

X extends Throwable

toList

public List<T> toList()

Returns:

toListIfNotNull

public List<T> toListIfNotNull()

To list if not null.

Returns:

toSet

public Set<T> toSet()

Returns:

toSetIfNotNull

public Set<T> toSetIfNotNull()

To set if not null.

Returns:

toImmutableList

public ImmutableList<T> toImmutableList()

To immutable list.

Returns:

toImmutableListIfNotNull

public ImmutableList<T> toImmutableListIfNotNull()

To immutable list if not null.

Returns:

toImmutableSet

public ImmutableSet<T> toImmutableSet()

To immutable set.

Returns:

toImmutableSetIfNotNull

public ImmutableSet<T> toImmutableSetIfNotNull()

To immutable set if not null.

Returns:

toOptional

public u.Optional<T> toOptional()

Returns:

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

Parameters:

obj -

Returns:

hashCode

public int hashCode()

Overrides:

hashCode in class Object

Returns:

toString

public String toString()

Overrides:

toString in class Object

Returns: