| org.apache.commons.collections.Predicate |
 Known Indirect Subclasses
AllPredicate,
AndPredicate,
AnyPredicate,
EqualPredicate,
ExceptionPredicate,
FalsePredicate,
IdentityPredicate,
InstanceofPredicate,
NonePredicate,
NotNullPredicate,
NotPredicate,
NullIsExceptionPredicate,
NullIsFalsePredicate,
NullIsTruePredicate,
NullPredicate,
and
7 others.
| AllPredicate |
Predicate implementation that returns true if all the
predicates return true. |
| AndPredicate |
Predicate implementation that returns true if both the predicates return true. |
| AnyPredicate |
Predicate implementation that returns true if any of the
predicates return true. |
| EqualPredicate |
Predicate implementation that returns true if the input is the same object
as the one stored in this predicate by equals. |
| ExceptionPredicate |
Predicate implementation that always throws an exception. |
| FalsePredicate |
Predicate implementation that always returns false. |
| IdentityPredicate |
Predicate implementation that returns true if the input is the same object
as the one stored in this predicate. |
| InstanceofPredicate |
Predicate implementation that returns true if the input is an instanceof
the type stored in this predicate. |
| NonePredicate |
Predicate implementation that returns true if none of the
predicates return true. |
| NotNullPredicate |
Predicate implementation that returns true if the input is not null. |
| NotPredicate |
Predicate implementation that returns the opposite of the decorated predicate. |
| NullIsExceptionPredicate |
Predicate implementation that throws an exception if the input is null. |
| NullIsFalsePredicate |
Predicate implementation that returns false if the input is null. |
| NullIsTruePredicate |
Predicate implementation that returns true if the input is null. |
| NullPredicate |
Predicate implementation that returns true if the input is null. |
| OnePredicate |
Predicate implementation that returns true if only one of the
predicates return true. |
| OrPredicate |
Predicate implementation that returns true if either of the predicates return true. |
| PredicateDecorator |
Defines a predicate that decorates one or more other predicates. |
| TransformedPredicate |
Predicate implementation that transforms the given object before invoking
another Predicate. |
| TransformerPredicate |
Predicate implementation that returns the result of a transformer. |
| TruePredicate |
Predicate implementation that always returns true. |
| UniquePredicate |
Predicate implementation that returns true the first time an object is
passed into the predicate. |
|
Class Overview
Defines a functor interface implemented by classes that perform a predicate
test on an object.
A Predicate is the object equivalent of an if statement.
It uses the input object to return a true or false value, and is often used in
validation or filtering.
Standard implementations of common predicates are provided by
PredicateUtils. These include true, false, instanceof, equals, and,
or, not, method invokation and null testing.
Summary
| Public Methods |
|---|
|
abstract
boolean
|
evaluate(Object object)
Use the specified parameter to perform a test that returns true or false.
|
Public Methods
public
abstract
boolean
evaluate
(Object object)
Use the specified parameter to perform a test that returns true or false.
Parameters
| object
| the object to evaluate, should not be changed |