Question

I’ve ArrayList (get_unique) of type integer where in I have to insert only unique values in
it. how can I do it??

I’ve got it some idea to do the same in javascript but do not know how to do it in Java?

 <%
ArrayList<Integer> get_unique = new ArrayList<Integer>();
ArrayList<Integer> set_unique = new ArrayList<Integer>();
// how do it 
%>

---

<script language="JavaScript">
<!--
// note: you will need to populate the myList() array with values!
var myList = new Array(); 
var uniqueList = new Array();
var uniqueListIndex = 0;

for (i=0;i<myList.length;i++) {
    var temp = myList[i];
    var unique = true;
    for (j=0;j<uniqueList.length;j++) {
        if (temp == uniqueList[j]) {
            unique = false;
            break;
        }
    }

    if (unique == true) {
        uniqueList[uniqueListIndex] = temp;
        uniqueListIndex++;
    } 
}
</script>

Answer 1

Just use Set<Integer> instead.

Set<Integer> unique = new LinkedHashSet<Integer>();

Duplicate entries will be automatically merged with existing entries. Note that using the LinkedHashSet implementation will also maintain the insertion order like as in an ArrayList, while a HashSet implementation wouldn’t maintain the insertion order. If you’d prefer automagic sort of entries, then use the TreeSet implementation instead.

See also:

• Java Tutorial – Collections