net.automatalib.commons.util.functions

Class FunctionsUtil

java.lang.Object

net.automatalib.commons.util.functions.FunctionsUtil

public final class FunctionsUtil
extends Object

This class provides utility methods for Java 8 Function objects (and for the corresponding primitive specializations).

Author:

Malte Isberner

Method Summary

Modifier and Type	Method and Description
static <R> BiIntFunction<? extends R>	safeDefault(@Nullable BiIntFunction<R> func) Returns a default function if the argument is null.
static <T,R> Function<T,? extends R>	safeDefault(@Nullable Function<T,R> func) Returns a default function if the argument is null.
static <R> IntFunction<? extends R>	safeDefault(@Nullable IntFunction<R> func) Returns a default function if the argument is null.
static <T> Predicate<T>	safeToFalse(@Nullable Predicate<T> func)
static <T> Predicate<T>	safeToTrue(@Nullable Predicate<T> func)

Methods inherited from class java.lang.Object

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

Method Detail

safeDefault

public static <T,R> Function<T,? extends R> safeDefault(@Nullable Function<T,R> func)

Returns a default function if the argument is null. The default function's Function#apply(Object) apply method will always return null. If a non-null function is passed to this method, it is returned as-is.

Parameters:

func - the function reference (may be null)

Returns:

a non-null object identical to the passed function, if it is non-null, or a function object always returning null otherwise

safeDefault

public static <R> IntFunction<? extends R> safeDefault(@Nullable IntFunction<R> func)

Returns a default function if the argument is null. The default function's apply method will always return null. If a non-null function is passed to this method, it is returned as-is.

Parameters:

func - the function reference (may be null)

Returns:

a non-null object identical to the passed function, if it is non-null, or a function object always returning null otherwise

safeDefault

public static <R> BiIntFunction<? extends R> safeDefault(@Nullable BiIntFunction<R> func)

Returns a default function if the argument is null. The default function's apply method will always return null. If a non-null function is passed to this method, it is returned as-is.

Parameters:

func - the function reference (may be null)

Returns:

a non-null object identical to the passed function, if it is non-null, or a function object always returning null otherwise

safeToTrue

public static <T> Predicate<T> safeToTrue(@Nullable Predicate<T> func)

safeToFalse

public static <T> Predicate<T> safeToFalse(@Nullable Predicate<T> func)