org.conqat.lib.commons.predicate

Class PredicateUtils

java.lang.Object

org.conqat.lib.commons.predicate.PredicateUtils

public class PredicateUtils
extends java.lang.Object

Utility methods for working with predicates.

Constructor Summary

Constructors

Constructor and Description
PredicateUtils()

Method Summary

Modifier and Type	Method and Description
static <T> java.util.function.Predicate<T>	alwaysTrue() Returns a predicate that always returns true.
static <T> java.util.function.Predicate<T>	not(java.util.function.Predicate<T> predicate) Negates the given predicate (returns false if the given predicate returns true and vice versa).
static <T> java.util.List<T>	obtainContained(java.util.Collection<T> input, java.util.function.Predicate<? super T> predicate) Returns all input elements that are contained in the set described by the predicate.
static <T> java.util.List<T>	obtainNonContained(java.util.Collection<T> input, java.util.function.Predicate<? super T> predicate) Returns all input elements that are not contained in the set described by the predicate.
static <T> Pair<java.util.List<T>,java.util.List<T>>	splitContainedNonContained(java.util.Collection<T> input, java.util.function.Predicate<? super T> predicate) Efficiently splits the list of input elements into two lists. The first consists of all input elements that are contained in the set described by the predicate. The second consists of all input elements that are not contained in the set described by the predicate. Efficiently in this case means that only one iteration through the list is needed to split into two lists.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PredicateUtils

public PredicateUtils()

Method Detail

obtainContained

public static <T> java.util.List<T> obtainContained(java.util.Collection<T> input,
                                                    java.util.function.Predicate<? super T> predicate)

Returns all input elements that are contained in the set described by the predicate.

Type Parameters:

T - Type in collection.

splitContainedNonContained

public static <T> Pair<java.util.List<T>,java.util.List<T>> splitContainedNonContained(java.util.Collection<T> input,
                                                                                       java.util.function.Predicate<? super T> predicate)

Efficiently splits the list of input elements into two lists.
The first consists of all input elements that are contained in the set described by the predicate.
The second consists of all input elements that are not contained in the set described by the predicate.
Efficiently in this case means that only one iteration through the list is needed to split into two lists.

Parameters:

input - the list of input elements.

predicate - the Predicate used to decide containment.

obtainNonContained

public static <T> java.util.List<T> obtainNonContained(java.util.Collection<T> input,
                                                       java.util.function.Predicate<? super T> predicate)

Returns all input elements that are not contained in the set described by the predicate.

alwaysTrue

public static <T> java.util.function.Predicate<T> alwaysTrue()

Returns a predicate that always returns true.

not

public static <T> java.util.function.Predicate<T> not(java.util.function.Predicate<T> predicate)

Negates the given predicate (returns false if the given predicate returns true and vice versa).