Assigning ArrayList Array in Java

Question

I was wondering if it is possible to assign an ArrayList array in Java.

Answer 1

You can use Arrays.asList() :

 Type[] anArray = ... ArrayList<Type> aList = new ArrayList<Type>(Arrays.asList(anArray)); 

or alternatively Collections.addAll() :

 ArrayList<Type> aList = new ArrayList<Type>(); Collections.addAll(theList, anArray); 

Note that you are not randomly assigning an array to the list (well, you cannot do this), but I think this is the end result you are looking for.

Answer 2

The Arrays class contains the asList method, which you can use as follows:

 String[] words = ...; List<String> wordList = Arrays.asList(words); 

Answer 3

If you import or you have an array (type strings) in your code, and you need to convert it to arraylist (offcourse string), then it is better to use collections. eg:

 String array1[] = getIntent().getExtras().getStringArray("key1"); or String array1[] = ... then List<String> allEds = new ArrayList<String>(); Collections.addAll(allEds, array1); 

Answer 4

It works

  int[] ar = {10, 20, 20, 10, 10, 30, 50, 10, 20}; ArrayList<Integer> list = new ArrayList<>(); for(int i:ar){ list.add(new Integer(i)); } System.out.println(list.toString()); // prints : [10, 20, 20, 10, 10, 30, 50, 10, 20]