How to count the number of occurrences of an element in a List

Question

I have an ArrayList, a Collection class of Java, as follows:

ArrayList animals = new ArrayList();
animals.add(\"bat\         


        

Answer 1

Map hm = new HashMap();
for(String i : animals) {
    Integer j = hm.get(i);
    hm.put(i,(j==null ? 1 : j+1));
}
for(Map.Entry val : hm.entrySet()) {
    System.out.println(val.getKey()+" occurs : "+val.getValue()+" times");
}