Java 8 lambda expression for list/array conversion

1). Convert List to List ( List of Strings to List of Integers)

List<Integer>  integerList =; 

// the longer full lambda version: 
List<Integer>  integerList  = -> Integer.parseInt(s)).collect(Collectors.toList());

2). Convert List to int[](List of Strings to int array)

int[] intArray =;

3). Convert String[] to List ( String array to List of Integers)

List<Integer>  integerList = Stream.of(array).map(Integer::parseInt).collect(Collectors.toList());

4). Convert String[] to int[] (String array to int array)

int[] intArray = Stream.of(stringArray).mapToInt(Integer::parseInt).toArray();

5). Convert String[] to List (String array to Double List)

List<Double> doubleList = Stream.of(stringArray).map(Double::parseDouble).collect(Collectors.toList());

6). Convert int[] to String[] (int array to String array)

String[] stringArray =[]::new);

7).  Convert 2D int[][] to List> ( 2D int array to nested Integer List)

List<Integer>  list =;


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