de.unkrig.commons.lang.protocol
Class PredicateUtil

java.lang.Object
  de.unkrig.commons.lang.protocol.PredicateUtil

public final class PredicateUtil
extends java.lang.Object

Various Predicate-related utility methods.

Method Summary

static Predicate<java.lang.Object>	after(long expirationTime) Returns a Predicate<Object> that evaluates to true iff the current time is after the given expiration time.
static <T> Predicate<T>	always()
static <T> Predicate<T>	and(Predicate<? super T> p1, Predicate<? super T> p2) Returns a Predicate which returns true iff both p1 and p2 return true for any given subject.
static <T,EX extends java.lang.RuntimeException> Predicate<T>	asPredicate(PredicateWhichThrows<T,EX> source) Converts a PredicateWhichThrows into a Predicate, which is possible iff the source's exception is a subclass of RuntimeException and the source's element type is a subclass of the target's element type.
static <T,EX extends java.lang.Throwable> PredicateWhichThrows<T,EX>	asPredicateWhichThrows(Predicate<? super T> source) Converts a Predicate into a PredicateWhichThrows, which is possible iff the source's element type is a subclass of the target's element type.
static <C extends java.lang.Comparable<C>> Predicate<C>	between(C min, C max)
static <T> Predicate<T>	contains(java.util.Collection<? extends T> collection)
static <K> Predicate<K>	containsKey(java.util.Map<K,?> map)
static <K> Predicate<K>	containsKey(Mapping<K,?> mapping)
static <C extends java.lang.Comparable<C>> Predicate<C>	equal(C other)
static <T> Predicate<T>	equals(T other) Value equality
static <T extends Predicate<java.lang.String>> T	forString(java.lang.String format, T delegate) Returns a predicate that evaluates the format against the delegate after each "*" in the format has been replaced with the subject.
static <C extends java.lang.Comparable<C>> Predicate<C>	greater(C other)
static <C extends java.lang.Comparable<C>> Predicate<C>	greaterEqual(C other)
static <C extends java.lang.Comparable<C>> Predicate<C>	less(C other)
static <C extends java.lang.Comparable<C>> Predicate<C>	lessEqual(C other)
static <T> Predicate<T>	never()
static <T> Predicate<T>	not(Predicate<T> delegate)
static <C extends java.lang.Comparable<C>> Predicate<C>	notEqual(C other)
static <T> Predicate<T>	notEquals(T other) Value equality
static <T> Predicate<T>	or(Predicate<? super T> p1, Predicate<? super T> p2)

Methods inherited from class java.lang.Object

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

Method Detail

always

public static <T> Predicate<T> always()

Returns:

A Predicate who's Predicate.evaluate(Object) method always returns true.

never

public static <T> Predicate<T> never()

Returns:

A Predicate who's Predicate.evaluate(Object) method always returns false.

and

public static <T> Predicate<T> and(Predicate<? super T> p1,
                                   Predicate<? super T> p2)

Returns a Predicate which returns true iff both p1 and p2 return true for any given subject.

Notice: A new predicate object needs to be allocated only if neither of the arguments is never() or always().

or

public static <T> Predicate<T> or(Predicate<? super T> p1,
                                  Predicate<? super T> p2)

Returns:

A Predicate which returns true if p1 or p2 returns true for a given subject.

not

public static <T> Predicate<T> not(Predicate<T> delegate)

Returns:

A Predicate which returns true iff the delegate returns false for any given subject.

less

public static <C extends java.lang.Comparable<C>> Predicate<C> less(C other)

Returns:

A Predicate which returns true iff a given subject is less than the other.

lessEqual

public static <C extends java.lang.Comparable<C>> Predicate<C> lessEqual(C other)

Returns:

A Predicate which returns true iff a given subject is less than or equal to the other.

greater

public static <C extends java.lang.Comparable<C>> Predicate<C> greater(C other)

Returns:

A Predicate which returns true iff a given subject is greater than the other.

greaterEqual

public static <C extends java.lang.Comparable<C>> Predicate<C> greaterEqual(C other)

Returns:

A Predicate which returns true iff a given subject is greater than or equal to the other.

equal

public static <C extends java.lang.Comparable<C>> Predicate<C> equal(C other)

Returns:

A Predicate which returns true iff a given subject is (arithmetically) equal to the other.

notEqual

public static <C extends java.lang.Comparable<C>> Predicate<C> notEqual(C other)

Returns:

A Predicate which returns true iff a given subject is (arithmetically) not equal to the other.

between

public static <C extends java.lang.Comparable<C>> Predicate<C> between(C min,
                                                                       C max)

Returns:

min <= subject <= max, or, if min > max: subject >= min || subject <= max

equals

public static <T> Predicate<T> equals(T other)

Value equality

notEquals

public static <T> Predicate<T> notEquals(T other)

Value equality

after

public static Predicate<java.lang.Object> after(long expirationTime)

Returns a Predicate<Object> that evaluates to true iff the current time is after the given expiration time.

(The returned predicate ignores its subject argument.)

forString

public static <T extends Predicate<java.lang.String>> T forString(java.lang.String format,
                                                                  T delegate)

Returns a predicate that evaluates the format against the delegate after each "*" in the format has been replaced with the subject. with

asPredicateWhichThrows

public static <T,EX extends java.lang.Throwable> PredicateWhichThrows<T,EX> asPredicateWhichThrows(Predicate<? super T> source)

Converts a Predicate into a PredicateWhichThrows, which is possible iff the source's element type is a subclass of the target's element type.

Type Parameters:

T - The subject type

EX - The target predicate's exception

asPredicate

public static <T,EX extends java.lang.RuntimeException> Predicate<T> asPredicate(PredicateWhichThrows<T,EX> source)

Converts a PredicateWhichThrows into a Predicate, which is possible iff the source's exception is a subclass of RuntimeException and the source's element type is a subclass of the target's element type.

Type Parameters:

T - The predicate subject type

EX - The source predicate's exception

contains

public static <T> Predicate<T> contains(java.util.Collection<? extends T> collection)

Returns:

A predicate which checks whether the given collection contains the subject

containsKey

public static <K> Predicate<K> containsKey(java.util.Map<K,?> map)

Returns:

A Predicate that evaluates to true iff the map contains a key equal to the predicate subject

containsKey

public static <K> Predicate<K> containsKey(Mapping<K,?> mapping)

Returns:

A Predicate that evaluates to true iff the mapping contains a key equal to the predicate subject