T - The type of the optional value.public final class Some<T> extends Object implements Option<T>, Serializable
Option. It contains a value which may be null. However, to
create an Option containing null, new Some(null) has to be called. In all other cases
Option.of(Object) is sufficient.| Constructor and Description |
|---|
Some(T value)
Creates a new Some containing the given value.
|
| Modifier and Type | Method and Description |
|---|---|
default <U> boolean |
corresponds(Iterable<U> that,
java.util.function.BiPredicate<? super T,? super U> predicate)
Tests whether every element of this iterable relates to the corresponding element of another iterable by
satisfying a test predicate.
|
default boolean |
eq(Object o)
A smoothing replacement for
equals. |
boolean |
equals(Object obj)
Clarifies that values have a proper equals() method implemented.
|
default boolean |
exists(java.util.function.Predicate<? super T> predicate)
Checks, if an element exists such that the predicate holds.
|
default boolean |
forAll(java.util.function.Predicate<? super T> predicate)
Checks, if the given predicate holds for all elements.
|
default void |
forEach(java.util.function.Consumer<? super T> action)
Performs an action on each element.
|
T |
get()
Gets the underlying value or throws if no value is present.
|
int |
hashCode()
Clarifies that values have a proper hashCode() method implemented.
|
boolean |
isEmpty()
Returns true, if this is
None, otherwise false, if this is Some. |
static Some<Void> |
nothing()
Return the singleton instance of
Some<Void>. |
default void |
stderr()
Sends the string representations of this value to the standard error stream System.err.
|
default void |
stdout()
Sends the string representations of this value to the standard output stream System.out.
|
default Object[] |
toJavaArray()
Converts this value to an untyped Java array.
|
String |
toString()
Clarifies that values have a proper toString() method implemented.
|
clone, finalize, getClass, notify, notifyAll, wait, wait, waitfilter, flatMap, getOption, isDefined, isSingletonType, iterator, map, none, of, ofOptional, orElse, orElseGet, orElseThrow, peek, some, whenfoldLeft, foldRight, get, ifDefined, ifDefined, ifEmpty, ifEmpty, orElseTry, out, out, toArray, toCharSeq, toJavaArray, toJavaList, toJavaMap, toJavaOptional, toJavaSet, toJavaStream, toLazy, toList, toMap, toOption, toQueue, toSet, toStack, toStream, toTree, toTry, toTry, toVectorfold, fold, foldLeft, foldMap, foldRightlift, lift, lift, lift, lift, lift, lift, liftspliteratorpublic Some(T value)
value - A value, may be nullpublic static Some<Void> nothing()
Some<Void>.NOTHINGpublic T get()
Valuepublic boolean isEmpty()
OptionNone, otherwise false, if this is Some.public boolean equals(Object obj)
Valuepublic int hashCode()
ValueSee Object.hashCode().
public String toString()
ValueSee Object.toString().
public <U> boolean corresponds(Iterable<U> that, java.util.function.BiPredicate<? super T,? super U> predicate)
U - Component type of that iterablethat - the other iterablepredicate - the test predicate, which relates elements from both iterablestrue if both iterables have the same length and predicate(x, y)
is true for all corresponding elements x of this iterable and y of that,
otherwise false.public boolean eq(Object o)
equals. It is similar to Scala's == but better in the way
that it is not limited to collection types, e.g. Some(1) eq List(1), None eq Failure(x) etc.
In a nutshell: eq checks congruence of structures and equality of contained values.
Example:
// ((1, 2), ((3))) => structure: (()(())) values: 1, 2, 3
final Iterable<?> i1 = List.of(List.of(1, 2), Arrays.asList(List.of(3)));
final Iterable<?> i2 = Queue.of(Stream.of(1, 2), List.of(Lazy.of(() -> 3)));
assertThat(i1.eq(i2)).isTrue();
o == this : true
o instanceof javaslang.Iterable : iterable elements are eq, non-iterable elements equals, for all (o1, o2) in (this, o)
o instanceof java.lang.Iterable : this eq Iterator.of((java.lang.Iterable<?>) o);
otherwise : false
o - An objectpublic boolean exists(java.util.function.Predicate<? super T> predicate)
predicate - A PredicateNullPointerException - if predicate is nullpublic boolean forAll(java.util.function.Predicate<? super T> predicate)
predicate - A PredicateNullPointerException - if predicate is nullpublic void forEach(java.util.function.Consumer<? super T> action)
forEach in interface Iterable<T>action - A ConsumerNullPointerException - if action is nullpublic Object[] toJavaArray()
public void stderr()
IllegalStateException - if PrintStream.checkError() is true after writing to stderr.public void stdout()
IllegalStateException - if PrintStream.checkError() is true after writing to stdout.Copyright © 2015. All Rights Reserved.