Find max element in Java ArrayList

Question

I have such simple code:

import java.util.ArrayList;
import java.util.List;

public class Main {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        Integer[] tab = {2324,1,2,2324,3,45,1,5,0,9,13,2324,1,3,9,8,4,2,1};
        Integer max = 2324;
        List<Integer> indexes = new ArrayList<Integer>();
            for (int e = 0; e < tab.length; e++) {
                if (tab[e] == max) {
                    indexes.add(new Integer(e));
                    System.out.println("Found max");
                }
            }
    }
}

The main problem here is I want to find every index in my tab where the max value is. For now on, it doesnt work - it doesnt display Found max message even once, although it should do it 3 times. Wheres the problem?

Ok, this finally worked, thanks all of you people:

public static void main(String[] args) {
        Integer[] tab = {2324,1,2,2324,3,45,1,5,0,9,13,2324,1,3,9,8,4,2,1};
        Integer max = 2324;
        List<Integer> indexes = new ArrayList<Integer>();
            for (int e = 0; e < tab.length; e++) {
                if (tab[e].intValue() == max.intValue()) {
                    indexes.add(Integer.valueOf(e));
                    System.out.println("Found max");
                }
            }
    }

Answer 1

Change

Integer[] tab = {2324,1,2,2324,3,45,1,5,0,9,13,2324,1,3,9,8,4,2,1};

to

int[] tab = {2324,1,2,2324,3,45,1,5,0,9,13,2324,1,3,9,8,4,2,1};

Integer objects are only precached for the values from -128 to 127.

---

If you want to leave it Integer you can change

if (tab[e] == max) {

to

if (tab[e].equals(max)) {

because it will then check for object equality, and not reference equality.

Answer 2

That's because you are comparing with == and not equals.