org.adroitlogic.x.utils

Class ListUtils

java.lang.Object

org.adroitlogic.x.utils.ListUtils

public class ListUtils
extends Object

Utility class for handling Java list data structures

Since:

17.01

Author:

Ruwan Linton, Udith Gunaratna

Constructor Summary

Constructors

Constructor and Description
ListUtils()

Method Summary

Modifier and Type	Method and Description
static <T> List<T>	cloneList(List<T> originalList) Creates a clone of a given List.
static Optional<String>	getStringPairValueWithKey(List<StringPair> stringPairList, String key) If the given stringPairList contains a StringPair instance with the given key as its StringPair.leftValue, retrieves its StringPair.rightValue
static boolean	hasStringPairWithKey(List<StringPair> stringPairList, String key) Checks whether the given stringPairList contains a StringPair instance with the given key as its StringPair.leftValue
static <T> List<T>	modifiableList(T... entries) Creates a modifiable list from the given set of typed values in the entries
static <T> List<T>	toListOfType(List<Object> list, Class<T> type) Converts a list of objects to a list of given type
static List<String>	toStringList(List<Object> list) Converts a list of objects to a list of their String representations

Methods inherited from class java.lang.Object

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

Constructor Detail

ListUtils

public ListUtils()

Method Detail

modifiableList

@SafeVarargs
public static <T> List<T> modifiableList(T... entries)

Creates a modifiable list from the given set of typed values in the entries

Type Parameters:

T - the type of the list entities

Parameters:

entries - the array of values to be initially included in the modifiable list

Returns:

the typed list with the initial values added to it

toStringList

public static List<String> toStringList(List<Object> list)

Converts a list of objects to a list of their String representations

Parameters:

list - the list of Object to be converted

Returns:

the list of String representations

toListOfType

public static <T> List<T> toListOfType(List<Object> list,
                                       Class<T> type)

Converts a list of objects to a list of given type

Type Parameters:

T - the type of the elements in the resulting list

Parameters:

list - the list of Object to be converted

type - type to be converted to

Returns:

a list of type

Throws:

IllegalArgumentException - if any of the objects in the list cannot be converted to the given type

cloneList

public static <T> List<T> cloneList(List<T> originalList)

Creates a clone of a given List. The original and cloned lists will refer separate objects for Java immutable entries while both will refer the same objects for others.

Type Parameters:

T - the type of the values

Parameters:

originalList - the list to be cloned

Returns:

new instance of List with the contents of the original list, or empty list if the original list is null

hasStringPairWithKey

public static boolean hasStringPairWithKey(List<StringPair> stringPairList,
                                           String key)

Checks whether the given stringPairList contains a StringPair instance with the given key as its StringPair.leftValue

Parameters:

stringPairList - List of StringPairs to be checked

key - value to be checked as the left value of the matching StringPair

Returns:

true if a matching instance of StringPair found, false otherwise

getStringPairValueWithKey

public static Optional<String> getStringPairValueWithKey(List<StringPair> stringPairList,
                                                         String key)

If the given stringPairList contains a StringPair instance with the given key as its StringPair.leftValue, retrieves its StringPair.rightValue

Parameters:

stringPairList - List of StringPairs to be checked

key - value to be checked as the left value of the matching StringPair

Returns:

an instance of Optional of type String containing the right value if a matching StringPair is found, Optional.EMPTY otherwise