- All Superinterfaces:
Predicate<T>
- All Known Implementing Classes:
BloomFilter
,CharMatcher
,Range
- Functional Interface:
- This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
java.util.function.Predicate
. Determines a
true or false value for a given input.
As this interface extends java.util.function.Predicate
, an instance of this type may
be used as a Predicate
directly. To use a java.util.function.Predicate
where a
com.google.common.base.Predicate
is expected, use the method reference
predicate::test
.
This interface is now a legacy type. Use java.util.function.Predicate
(or the
appropriate primitive specialization such as IntPredicate
) instead whenever possible.
Otherwise, at least reduce explicit dependencies on this type by using lambda expressions
or method references instead of classes, leaving your code easier to migrate in the future.
The Predicates
class provides common predicates and related utilities.
See the Guava User Guide article on the use of Predicate
.
- Since:
- 2.0
- Author:
- Kevin Bourrillion
-
Method Summary
Modifier and TypeMethodDescriptionboolean
Returns the result of applying this predicate toinput
(Java 8+ users, see notes in the class documentation above).boolean
Indicates whether another object is equal to this predicate.default boolean
-
Method Details
-
apply
Returns the result of applying this predicate toinput
(Java 8+ users, see notes in the class documentation above). This method is generally expected, but not absolutely required, to have the following properties:- Its execution does not cause any observable side effects.
- The computation is consistent with equals; that is,
Objects.equal
(a, b)
implies thatpredicate.apply(a) == predicate.apply(b))
.
- Throws:
NullPointerException
- ifinput
is null and this predicate does not accept null arguments
-
equals
Indicates whether another object is equal to this predicate.Most implementations will have no reason to override the behavior of
Object.equals(java.lang.Object)
. However, an implementation may also choose to returntrue
wheneverobject
is aPredicate
that it considers interchangeable with this one. "Interchangeable" typically means thatthis.apply(t) == that.apply(t)
for allt
of typeT
). Note that afalse
result from this method does not imply that the predicates are known not to be interchangeable. -
test
-