Java 8 lambda expression for list/array conversion
1). Convert List to List ( List of Strings to List of Integers) List<Integer> integerList = stringList.stream().map(Integer::parseInt).collect(Collectors.toList()); // the longer full lambda version: List<Integer> integerList = stringList.stream().map(s -> Integer.parseInt(s)).collect(Collectors.toList()); 2). Convert List to int[](List of Strings to int array) int[] intArray = stringList.stream().mapToInt(Integer::parseInt).toArray(); 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). Co