How do I count the occurrences of a number in an array?

courtesy: kodejava

import java.util.Map;

import java.util.HashMap;
import java.util.Iterator;

public class NumberOccurrenceInArray {
public static void main(String[] args) {
int[] numbers = new int[] {1, 8, 3, 4, 3, 2, 5, 7, 3, 1, 4, 5, 6, 4, 3};

Map map = new HashMap();
for (int i = 0; i < numbers.length; i++) {
int key = numbers[i];
if (map.containsKey(key)) {
int occurrence = map.get(key);
occurrence++;
map.put(key, occurrence);
} else {
map.put(key, 1);
}
}

Iterator iterator = map.keySet().iterator();
while (iterator.hasNext()) {
int key = (Integer) iterator.next();
int occurrence = map.get(key);

System.out.println(key + " occur " + occurrence + " time(s).");
}
}
}