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 <T,R> Function<T,R>	safeDefault(Function<T,R> func) Returns a default function if the argument is null.
static <R> IntFunction<R>	safeDefault(IntFunction<R> func) Returns a default function if the argument is null.
static <T> Predicate<T>	safeToFalse(Predicate<T> func)
static <T> Predicate<T>	safeToTrue(Predicate<T> func)

Methods inherited from class java.lang.Object

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

Method Detail

safeDefault

@Nonnull
public static <T,R> Function<T,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

@Nonnull
public static <R> IntFunction<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

safeToTrue

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

safeToFalse

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