de.alpharogroup.collections.list

Class OptionalListExtensions

java.lang.Object

de.alpharogroup.collections.list.OptionalListExtensions

public class OptionalListExtensions
extends Object

Extensions class for use with List objects

Constructor Summary

Constructors

Constructor and Description
OptionalListExtensions()

Method Summary

Modifier and Type	Method and Description
static <T> Optional<T>	getFirst(@NonNull List<T> list) Returns an Optional with the first object from the given List
static <T> Optional<T>	getLast(@NonNull List<T> list) Returns an Optional with the last object from the given List
static <T> Optional<T>	getNext(@NonNull List<T> list, T element) Gets the next element from the given List.
static <T> Optional<T>	getPrevious(@NonNull List<T> list, T element) Gets the previous element from the given List.
static <T> Optional<T>	removeFirst(@NonNull List<T> list) Returns an Optional with the first object if it was removed from the given List
static <T> Optional<T>	removeLast(@NonNull List<T> list) Returns an Optional with the last object if it was removed from the given List

Methods inherited from class java.lang.Object

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

Constructor Detail

OptionalListExtensions

public OptionalListExtensions()

Method Detail

getFirst

public static <T> Optional<T> getFirst(@NonNull
                                       @NonNull List<T> list)

Returns an Optional with the first object from the given List

Type Parameters:

T - the generic type of the elements

Parameters:

list - the List object

Returns:

an Optional with the first object from the given List or an empty Optional if the List is empty

getLast

public static <T> Optional<T> getLast(@NonNull
                                      @NonNull List<T> list)

Returns an Optional with the last object from the given List

Type Parameters:

T - the generic type of the elements

Parameters:

list - the List object

Returns:

an Optional with the last object from the given List or an empty Optional if the List is empty

removeFirst

public static <T> Optional<T> removeFirst(@NonNull
                                          @NonNull List<T> list)

Returns an Optional with the first object if it was removed from the given List

Type Parameters:

T - the generic type of the elements

Parameters:

list - the List object

Returns:

returns an Optional with the first object if it was removed from the given List or an empty Optional if the List is empty

removeLast

public static <T> Optional<T> removeLast(@NonNull
                                         @NonNull List<T> list)

Returns an Optional with the last object if it was removed from the given List

Type Parameters:

T - the generic type of the elements

Parameters:

list - the List object

Returns:

returns an Optional with the last object if it was removed from the given List or an empty Optional if the List is empty

getPrevious

public static <T> Optional<T> getPrevious(@NonNull
                                          @NonNull List<T> list,
                                          T element)

Gets the previous element from the given List. As start point is the given element

Type Parameters:

T - the generic type of elements

Parameters:

list - the list

element - the element

Returns:

an Optional with the previous element from the given List or an empty Optional if the List has no previous element

getNext

public static <T> Optional<T> getNext(@NonNull
                                      @NonNull List<T> list,
                                      T element)

Gets the next element from the given List. As start point is the given element

Type Parameters:

T - the generic type of elements

Parameters:

list - the list

element - the element

Returns:

an Optional with the next element from the given List or an empty Optional if the List has no next element