Question

I have an arraylist, say arr. Now this arraylist stores numbers as strings. now i want to convert this arraylist to integer type. So how can i do that???

ArrayList arr = new ArrayList();

String a="Mode set - In Service", b="Mode set - Out of Service";

if(line.contains(a) || line.contains(b)) {
    StringTokenizer st = new StringTokenizer(line, ":Mode set - Out of Service In Service");
    while(st.hasMoreTokens()) {
      arr.add(st.nextToken());  
    }
}

Answer 1

Since you’re using an untyped List arr, you’ll need to cast to String before performing parseInt:

List<Integer> arrayOfInts = new ArrayList<Integer>();
for (Object str : arr) {
   arrayOfInts.add(Integer.parseInt((String)str));
}

I recommend that you define arr as follows:

List<String> arr = new ArrayList<String>();

That makes the cast in the conversion unnecessary.